Overheating question................
09-04-2005, 06:57 PM
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Overheating question................ I asked this before, but I thought it would get fixed when I had the dealer replace my A/C system last week, so I'm asking again. The tech at the dealer said he can't see anything in front of the condensor or radiator and that everything looks normal as far as the overheating is concerned.
My engine temp runs below the 155 mark on the temp gauge 100% of the time no matter how hot it is down here in South Florida even if I drive around the city all day long in traffic.
As soon as I turn the A/C "on", the engine doesn't get hot, it overheats if I let. The needle goes right past the 210 mark and my engine detonates like crazy from the ridiculous heat.
If I'm cruising on the highway I have no problem, it stays cool. Fans are working perfectly too.
What in gods name would cause the engine to simply overheat, not just run hotter, but OVERHEAT, when the A/C is turned on.
NOTE*** I had this second engine rebuilt by ARE, this engine has this problem. The original engine NEVER overheated with the A/C on.
ALSO, does anyone sell aftermarket fans that will blow alot better than the stock fans?
Thank you, I'm at my wits end with this bullshit. I feel like taking the damn engine out and getting a new one already.
.
My engine temp runs below the 155 mark on the temp gauge 100% of the time no matter how hot it is down here in South Florida even if I drive around the city all day long in traffic.
As soon as I turn the A/C "on", the engine doesn't get hot, it overheats if I let. The needle goes right past the 210 mark and my engine detonates like crazy from the ridiculous heat.
If I'm cruising on the highway I have no problem, it stays cool. Fans are working perfectly too.
What in gods name would cause the engine to simply overheat, not just run hotter, but OVERHEAT, when the A/C is turned on.
NOTE*** I had this second engine rebuilt by ARE, this engine has this problem. The original engine NEVER overheated with the A/C on.
ALSO, does anyone sell aftermarket fans that will blow alot better than the stock fans?
Thank you, I'm at my wits end with this bullshit. I feel like taking the damn engine out and getting a new one already.
.
09-04-2005, 07:22 PM
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Have you put a scanner on it and monitored the temp while driving around? Autotap or whatever? Seems strange that it would overheat only when the AC is on. As far as the stock gauge goes, I wouldn't put much faith in it.
I wonder if you have some kind of electrical gremlin that is screwing with the fans only when the AC is on? And you have verified that the fans are kicking on when you turn the AC on?
I know you said the fans are working, but here's a quck primer on checking the fan operation from a thing I wrote up several years ago. Hope this helps.
This is from memory and for the 2000 ECM pin-outs.
I tapped into the wiring harness that runs over the pass wheelwell to the computer. To do a quick test, you can pull the large connector apart on the wheelwell and look look for the pins that correspond to the Dark Green wire (low speed fan relay control) and the Dark Blue wire (high speed fan relay control.
With the ignition off, take a probe or wire and touch the Dark green wire pin and put the other end to ground. The fans should come on low speed.
With the green wire still to ground, take another probe or wire and touch the pin that corresponds to the Dark blue wire and put the other end to ground. Fans should now come on high.
In other words the Dark Green wire to ground will run the fans on low. Both the Dark Green AND the Dark Blue to ground will run fans on high.
I wonder if you have some kind of electrical gremlin that is screwing with the fans only when the AC is on? And you have verified that the fans are kicking on when you turn the AC on?
I know you said the fans are working, but here's a quck primer on checking the fan operation from a thing I wrote up several years ago. Hope this helps.
This is from memory and for the 2000 ECM pin-outs.
I tapped into the wiring harness that runs over the pass wheelwell to the computer. To do a quick test, you can pull the large connector apart on the wheelwell and look look for the pins that correspond to the Dark Green wire (low speed fan relay control) and the Dark Blue wire (high speed fan relay control.
With the ignition off, take a probe or wire and touch the Dark green wire pin and put the other end to ground. The fans should come on low speed.
With the green wire still to ground, take another probe or wire and touch the pin that corresponds to the Dark blue wire and put the other end to ground. Fans should now come on high.
In other words the Dark Green wire to ground will run the fans on low. Both the Dark Green AND the Dark Blue to ground will run fans on high.
09-04-2005, 07:56 PM
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Originally Posted by gwj
Have you put a scanner on it and monitored the temp while driving around? Autotap or whatever? Seems strange that it would overheat only when the AC is on. As far as the stock gauge goes, I wouldn't put much faith in it.
I wonder if you have some kind of electrical gremlin that is screwing with the fans only when the AC is on? And you have verified that the fans are kicking on when you turn the AC on?
I know you said the fans are working, but here's a quck primer on checking the fan operation from a thing I wrote up several years ago. Hope this helps.
This is from memory and for the 2000 ECM pin-outs.
I tapped into the wiring harness that runs over the pass wheelwell to the computer. To do a quick test, you can pull the large connector apart on the wheelwell and look look for the pins that correspond to the Dark Green wire (low speed fan relay control) and the Dark Blue wire (high speed fan relay control.
With the ignition off, take a probe or wire and touch the Dark green wire pin and put the other end to ground. The fans should come on low speed.
With the green wire still to ground, take another probe or wire and touch the pin that corresponds to the Dark blue wire and put the other end to ground. Fans should now come on high.
In other words the Dark Green wire to ground will run the fans on low. Both the Dark Green AND the Dark Blue to ground will run fans on high.
I wonder if you have some kind of electrical gremlin that is screwing with the fans only when the AC is on? And you have verified that the fans are kicking on when you turn the AC on?
I know you said the fans are working, but here's a quck primer on checking the fan operation from a thing I wrote up several years ago. Hope this helps.
This is from memory and for the 2000 ECM pin-outs.
I tapped into the wiring harness that runs over the pass wheelwell to the computer. To do a quick test, you can pull the large connector apart on the wheelwell and look look for the pins that correspond to the Dark Green wire (low speed fan relay control) and the Dark Blue wire (high speed fan relay control.
With the ignition off, take a probe or wire and touch the Dark green wire pin and put the other end to ground. The fans should come on low speed.
With the green wire still to ground, take another probe or wire and touch the pin that corresponds to the Dark blue wire and put the other end to ground. Fans should now come on high.
In other words the Dark Green wire to ground will run the fans on low. Both the Dark Green AND the Dark Blue to ground will run fans on high.
Thanks for the write up, I'll have to do that. Also, A friend did scan my car before and my temps are off by about 30 degrees. The 155 mark on my gauge is about 185 degrees. The 210 mark is about 235. Thats why I know there's something wrong, it should never get to 230 degrees just driving around casually in the city on a hot day witgh the A/C on. By the time my needle is near the 210 mark, my engine is already way to hot.
When you say to ground the wires, do you mean touch a metal wire to the green/blue wire pins and than touch the other end of that wire to the car somewhere?
.
09-04-2005, 10:56 PM
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Is your coolant topped off and full? Don't hold me to it, but since you're in Florida where it doesn't get very cold you might be able to run more water in your radiator than normal. Usually it's about 50/50 of coolant to water, but you could try 60-70% water and 30-40% coolant mix instead and see if it makes any difference. Water is a better heat conductor than the coolant is.
Along with that you could try to add in some Water wetter or similar additive that can sometimes bring the temperatures down a bit. http://www.redlineoil.com/products_coolant.asp
This may or may not help, but it may be worth a shot if everything else checks out. What thermostat are you running? If it's stock (which I doubt) you could try a 160 T-stat also. The stock temperature gauge is basically an idiot gauge and is horribly inaccurate, so it's hard to say what the temp really is. You might be just borderline normally and when the A/C is on it just pushes it over the limit. You're not over heating on the highway because so much more air is blowing through the radiator taking the heat away. Keep in mind also since you've got almost 100 more cubes than a stock engine you're probably making quite a bit more heat.
Along with that you could try to add in some Water wetter or similar additive that can sometimes bring the temperatures down a bit. http://www.redlineoil.com/products_coolant.asp
This may or may not help, but it may be worth a shot if everything else checks out. What thermostat are you running? If it's stock (which I doubt) you could try a 160 T-stat also. The stock temperature gauge is basically an idiot gauge and is horribly inaccurate, so it's hard to say what the temp really is. You might be just borderline normally and when the A/C is on it just pushes it over the limit. You're not over heating on the highway because so much more air is blowing through the radiator taking the heat away. Keep in mind also since you've got almost 100 more cubes than a stock engine you're probably making quite a bit more heat.
Last edited by JF WS6; 09-04-2005 at 11:16 PM.
09-04-2005, 11:29 PM
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Originally Posted by JF WS6
Is your coolant topped off and full? Don't hold me to it, but since you're in Florida where it doesn't get very cold you might be able to run more water in your radiator than normal. Usually it's about 50/50 of coolant to water, but you could try 60-70% water and 30-40% coolant mix instead and see if it makes any difference. Water is a better heat conductor than the coolant is.
Along with that you could try to add in some Water wetter or similar additive that can sometimes bring the temperatures down a bit. http://www.redlineoil.com/products_coolant.asp
This may or may not help, but it may be worth a shot if everything else checks out. What thermostat are you running? If it's stock (which I doubt) you could try a 160 T-stat also. The stock temperature gauge is basically an idiot gauge and is horribly inaccurate, so it's hard to say what the temp really is. You might be just borderline normally and when the A/C is on it just pushes it over the limit. You're not over heating on the highway because so much more air is blowing through the radiator taking the heat away. Keep in mind also since you've got almost 100 more cubes than a stock engine you're probably making quite a bit more heat.
Along with that you could try to add in some Water wetter or similar additive that can sometimes bring the temperatures down a bit. http://www.redlineoil.com/products_coolant.asp
This may or may not help, but it may be worth a shot if everything else checks out. What thermostat are you running? If it's stock (which I doubt) you could try a 160 T-stat also. The stock temperature gauge is basically an idiot gauge and is horribly inaccurate, so it's hard to say what the temp really is. You might be just borderline normally and when the A/C is on it just pushes it over the limit. You're not over heating on the highway because so much more air is blowing through the radiator taking the heat away. Keep in mind also since you've got almost 100 more cubes than a stock engine you're probably making quite a bit more heat.
The 100 more cubes thing: My original 436 that ARE sent to me never overheated no matter what I did with the A/C "on". This newly rebuilt engine does, and has since day one. I have 160 T Stat too that I pulled out and checked in boiling water. I held a thermometer next to it and it opened up when it was supposed to.
I was thinking a water passage is blocked from a head gasket maybe...
I don't know.
09-05-2005, 12:25 AM
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Hmmm.... Well, that certainly eliminates a few possibilities. Have you ever emptied the cooling system since you've had the new engine back in? I would guess you have if you pulled the t-stat off. I would at least do that + a radiator flush if you haven't yet just to make sure there isn't any air trapped in there. LS1howto.com has good information that can step you through it if you haven't done it before.
The blocked water passage thing seems unlikely to me. Is your water pump working ok? I mean there's only so many things it could be. If everything seems to check out ok (waterpump, thermostat, full fluids no trapped air, working fans, no leaks) you might think about looking into a larger aftermarket radiator. It probably wouldn't be a bad thing considering your investment + the area you live in and how hot it gets. Also SLP makes a fan switch mod that would allow you to manually turn the fans on, but I don't know if that would help.
The blocked water passage thing seems unlikely to me. Is your water pump working ok? I mean there's only so many things it could be. If everything seems to check out ok (waterpump, thermostat, full fluids no trapped air, working fans, no leaks) you might think about looking into a larger aftermarket radiator. It probably wouldn't be a bad thing considering your investment + the area you live in and how hot it gets. Also SLP makes a fan switch mod that would allow you to manually turn the fans on, but I don't know if that would help.
09-05-2005, 02:04 AM
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Originally Posted by JF WS6
Hmmm.... Well, that certainly eliminates a few possibilities. Have you ever emptied the cooling system since you've had the new engine back in?
LS1howto.com has good information that can step you through it if you haven't done it before.
But I don't think that the problem because Norris Motorsports installed my engine and when I picked it up it was 50/50 Dextron/water and I had the same over heating problem when I turned the A/C on. With the A/C off it ran very cool like it does right now with the A/C "off".
Is your water pump working ok?
If everything seems to check out ok (waterpump, thermostat, full fluids no trapped air, working fans, no leaks)
you might think about looking into a larger aftermarket radiator.
How about the compressor clutch..could it be binded up and dragging my motor down alot more than a good clutch should? When they installed the new compressor at the dealer last week did it come with a new clutch?
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09-05-2005, 07:46 AM
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Originally Posted by Quickin
When you say to ground the wires, do you mean touch a metal wire to the green/blue wire pins and than touch the other end of that wire to the car somewhere?
.
Sorry I can't add anything else about the cooling problem that hasn't been covered.
Luck,
Gerald
09-05-2005, 10:31 AM
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This sounds to me like a fan temp settings problem.
A/C evaporator dumps heat onto the radiator and the
fans need to be on full time. I see a FAN1 enable /
disable speed settings pair that could perhaps be set
too low, cutting A/C FAN1? Also see no FAN2 so maybe
FAN1 is all you get w/ A/C on, and it just isn't enough
for the cooling airflow? Since rolling is OK it has to be
an airflow problem I think. Don't know why new motor
is hotter than old. Not missing any of the side-side
coolant tubes, is it?
Maybe you want to consider taking fan control away
from the PCM and running a thermostatic control like
the Hayden (or other), that works off the radiator
temp? I'd check the FAN2 turnon temps and bring
them in closer to the thermostat crackpoint (way
less than stock FAN2 setting temp of 234F) at least.
A/C evaporator dumps heat onto the radiator and the
fans need to be on full time. I see a FAN1 enable /
disable speed settings pair that could perhaps be set
too low, cutting A/C FAN1? Also see no FAN2 so maybe
FAN1 is all you get w/ A/C on, and it just isn't enough
for the cooling airflow? Since rolling is OK it has to be
an airflow problem I think. Don't know why new motor
is hotter than old. Not missing any of the side-side
coolant tubes, is it?
Maybe you want to consider taking fan control away
from the PCM and running a thermostatic control like
the Hayden (or other), that works off the radiator
temp? I'd check the FAN2 turnon temps and bring
them in closer to the thermostat crackpoint (way
less than stock FAN2 setting temp of 234F) at least.
09-05-2005, 02:35 PM
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Originally Posted by Quickin
How about the compressor clutch..could it be binded up and dragging my motor down alot more than a good clutch should? When they installed the new compressor at the dealer last week did it come with a new clutch?
When I mentioned LS1howto.com, I was talking about the procedure basically of draining and refilling the coolant as it is done for the head swap procedure. Basically a flush is just emptying the contents of the radiator out into a bucket, filling the radiator again with some type of radiator flush additive/water whatever is recommended, running the engine a bit to warm it up to open the thermostat, then draining that and filling it up again. There's usually directions on the back of the radiator flush.
I agree with Jimmy Blue at this point, you know that it runs ok on the highway with the high airflow, so it sounds like that is the problem. That's why I suggested the larger radiator and or the fan switch mod. The easiest thing you could try is to do the fan switch mod and whenever you want to run the A/C during street driving you could manually turn both fans on before you turn the A/C on and see if that makes a difference. If not, I still say a larger radiator with more cooling surface might be necessary to look into. I know it doesn't make much sense compared to your last motor, but if everything else checks out ok I don't know what else it could be?
09-05-2005, 03:05 PM
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Originally Posted by JF WS6
I doubt this is it also.... you probably have all new parts if you had your entire A/C system replaced.
When I mentioned LS1howto.com, I was talking about the procedure basically of draining and refilling the coolant as it is done for the head swap procedure. Basically a flush is just emptying the contents of the radiator out into a bucket, filling the radiator again with some type of radiator flush additive/water whatever is recommended, running the engine a bit to warm it up to open the thermostat, then draining that and filling it up again. There's usually directions on the back of the radiator flush.
I agree with Jimmy Blue at this point, you know that it runs ok on the highway with the high airflow, so it sounds like that is the problem. That's why I suggested the larger radiator and or the fan switch mod. The easiest thing you could try is to do the fan switch mod and whenever you want to run the A/C during street driving you could manually turn both fans on before you turn the A/C on and see if that makes a difference. If not, I still say a larger radiator with more cooling surface might be necessary to look into. I know it doesn't make much sense compared to your last motor, but if everything else checks out ok I don't know what else it could be?
When I mentioned LS1howto.com, I was talking about the procedure basically of draining and refilling the coolant as it is done for the head swap procedure. Basically a flush is just emptying the contents of the radiator out into a bucket, filling the radiator again with some type of radiator flush additive/water whatever is recommended, running the engine a bit to warm it up to open the thermostat, then draining that and filling it up again. There's usually directions on the back of the radiator flush.
I agree with Jimmy Blue at this point, you know that it runs ok on the highway with the high airflow, so it sounds like that is the problem. That's why I suggested the larger radiator and or the fan switch mod. The easiest thing you could try is to do the fan switch mod and whenever you want to run the A/C during street driving you could manually turn both fans on before you turn the A/C on and see if that makes a difference. If not, I still say a larger radiator with more cooling surface might be necessary to look into. I know it doesn't make much sense compared to your last motor, but if everything else checks out ok I don't know what else it could be?
I'd like to just buy two new aftermarket higher flowing fans if they're available somewhere. Mine are 7 1/2 years old.
09-05-2005, 03:09 PM
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Originally Posted by jimmyblue
This sounds to me like a fan temp settings problem.
A/C evaporator dumps heat onto the radiator and the
fans need to be on full time. I see a FAN1 enable /
disable speed settings pair that could perhaps be set
too low, cutting A/C FAN1? Also see no FAN2 so maybe
FAN1 is all you get w/ A/C on, and it just isn't enough
for the cooling airflow? Since rolling is OK it has to be
an airflow problem I think. Don't know why new motor
is hotter than old. Not missing any of the side-side
coolant tubes, is it?
Maybe you want to consider taking fan control away
from the PCM and running a thermostatic control like
the Hayden (or other), that works off the radiator
temp? I'd check the FAN2 turnon temps and bring
them in closer to the thermostat crackpoint (way
less than stock FAN2 setting temp of 234F) at least.
A/C evaporator dumps heat onto the radiator and the
fans need to be on full time. I see a FAN1 enable /
disable speed settings pair that could perhaps be set
too low, cutting A/C FAN1? Also see no FAN2 so maybe
FAN1 is all you get w/ A/C on, and it just isn't enough
for the cooling airflow? Since rolling is OK it has to be
an airflow problem I think. Don't know why new motor
is hotter than old. Not missing any of the side-side
coolant tubes, is it?
Maybe you want to consider taking fan control away
from the PCM and running a thermostatic control like
the Hayden (or other), that works off the radiator
temp? I'd check the FAN2 turnon temps and bring
them in closer to the thermostat crackpoint (way
less than stock FAN2 setting temp of 234F) at least.
I personally don't know how to do all this stuff you mentioned. I need to have these fans and PCM settings checked by a tech I guess. At least rule that out before going to deep.
Thanks.
09-05-2005, 08:00 PM
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Well, to review. We have suggested the basics, like how to check if the fans actually function at both low/high settings independent of PCM commands.
Suggestion to check if the fans are functioning correctly with AC running. (dealer would be more help here if you don't have aftermarket temp gauge).
Whether or not you have a Trans cooler doesn't seem to come into play as at cruising speed the converter should be locked up, hmm?
Suggestion to check PCM programming (have you ever had programming of any kind?) to see if fan turn on temps are in line with what is needed (back to suggestion 2).
I'm kind of at a loss here to figure out why the AC would contribute to higher temps, even if it was costing the engine a few more HP due to some compressor drag.
It just about always comes back to the fans to me.??
Is it always when the AC is on, only, never in heavy stop and go traffic with the AC off????
Suggestion to check if the fans are functioning correctly with AC running. (dealer would be more help here if you don't have aftermarket temp gauge).
Whether or not you have a Trans cooler doesn't seem to come into play as at cruising speed the converter should be locked up, hmm?
Suggestion to check PCM programming (have you ever had programming of any kind?) to see if fan turn on temps are in line with what is needed (back to suggestion 2).
I'm kind of at a loss here to figure out why the AC would contribute to higher temps, even if it was costing the engine a few more HP due to some compressor drag.
It just about always comes back to the fans to me.??
Is it always when the AC is on, only, never in heavy stop and go traffic with the AC off????
09-05-2005, 09:36 PM
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Originally Posted by gwj
Well, to review. We have suggested the basics, like how to check if the fans actually function at both low/high settings independent of PCM commands.
Suggestion to check if the fans are functioning correctly with AC running. (dealer would be more help here if you don't have aftermarket temp gauge).
Whether or not you have a Trans cooler doesn't seem to come into play as at cruising speed the converter should be locked up, hmm?
Suggestion to check PCM programming (have you ever had programming of any kind?) to see if fan turn on temps are in line with what is needed (back to suggestion 2).
I'm kind of at a loss here to figure out why the AC would contribute to higher temps, even if it was costing the engine a few more HP due to some compressor drag.
It just about always comes back to the fans to me.??
Is it always when the AC is on, only, never in heavy stop and go traffic with the AC off????
Suggestion to check if the fans are functioning correctly with AC running. (dealer would be more help here if you don't have aftermarket temp gauge).
Whether or not you have a Trans cooler doesn't seem to come into play as at cruising speed the converter should be locked up, hmm?
Suggestion to check PCM programming (have you ever had programming of any kind?) to see if fan turn on temps are in line with what is needed (back to suggestion 2).
I'm kind of at a loss here to figure out why the AC would contribute to higher temps, even if it was costing the engine a few more HP due to some compressor drag.
It just about always comes back to the fans to me.??
Is it always when the AC is on, only, never in heavy stop and go traffic with the AC off????
Is the condensor on the drivers side or the passengers side? Is it in front or behind the radiator? I can't find it.
I think you may be right after all the info in this thread...the fan is probably not going into HIGH setting. I'll go to the dealer tomorrow.
09-06-2005, 06:35 AM
#15
Quickin,
I would double check what the actual temps are via scanner though you said you did in the past. The F-body coolant temp gauge is notoriously off one way or the other, but rarely right.
What it sounds like to me is somewhat normal, though not what people wnat. In Florida, and more so South Florida, the temps can really be tough in traffic to say the least. Add 90 more cubes and still a stock radiator, makes it more prevelent. Is it overheating? probably not as the stock fan settings do not come on till 229* on fan 1 and 235* on fan 2.
The best example I can give is my 2000 C5 Vette I owned up till last year. Forged 346 with everything and runs low 11's on street tires. Usually she would run 185-200 with the A/C on cruising or any condition. I have the stock radiator, stock fans, 160* thermostat, fans on at 185-190*F and it was an M6. I had just 3 quearts coolant with a bottle of Water Wetter and the rest distilled water.
I was in Miami for a wedding and got caught in stopped traffic on I-95 around 5PM. Outside temp was 98*, heat off the road was probably 140-150* or better, hot exhaust from the car in front of me heading towards the radiator as well as the A/C condensor 1" in front of the stock radiator generating heat. All this had the temps running 225-230*, but no other issues. Basically it was exchanging as much heat as possible for the given situation. Was she overheating? No, just running on the hotter side of normal. Once we got rolling over 25-30MPH agin constantly the temps came back down to 200* and under.
If you were to do a larger radiator and better fans it may help, but I would not be surprised to see the higher temps still on a hot South Florida day with the A/C on in traffic. Just sometimes a part of living here. Most likely this was going on before also. You just make it the best you can make it. If she is pinging, then maybe we need to change some of the temp to timing parameters to keep her safe.
Hope this helps.
Mike Norris
I would double check what the actual temps are via scanner though you said you did in the past. The F-body coolant temp gauge is notoriously off one way or the other, but rarely right.
What it sounds like to me is somewhat normal, though not what people wnat. In Florida, and more so South Florida, the temps can really be tough in traffic to say the least. Add 90 more cubes and still a stock radiator, makes it more prevelent. Is it overheating? probably not as the stock fan settings do not come on till 229* on fan 1 and 235* on fan 2.
The best example I can give is my 2000 C5 Vette I owned up till last year. Forged 346 with everything and runs low 11's on street tires. Usually she would run 185-200 with the A/C on cruising or any condition. I have the stock radiator, stock fans, 160* thermostat, fans on at 185-190*F and it was an M6. I had just 3 quearts coolant with a bottle of Water Wetter and the rest distilled water.
I was in Miami for a wedding and got caught in stopped traffic on I-95 around 5PM. Outside temp was 98*, heat off the road was probably 140-150* or better, hot exhaust from the car in front of me heading towards the radiator as well as the A/C condensor 1" in front of the stock radiator generating heat. All this had the temps running 225-230*, but no other issues. Basically it was exchanging as much heat as possible for the given situation. Was she overheating? No, just running on the hotter side of normal. Once we got rolling over 25-30MPH agin constantly the temps came back down to 200* and under.
If you were to do a larger radiator and better fans it may help, but I would not be surprised to see the higher temps still on a hot South Florida day with the A/C on in traffic. Just sometimes a part of living here. Most likely this was going on before also. You just make it the best you can make it. If she is pinging, then maybe we need to change some of the temp to timing parameters to keep her safe.
Hope this helps.
Mike Norris
09-06-2005, 11:32 AM
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Originally Posted by Mike Norris
Quickin,
I would double check what the actual temps are via scanner though you said you did in the past. The F-body coolant temp gauge is notoriously off one way or the other, but rarely right.
What it sounds like to me is somewhat normal, though not what people wnat. In Florida, and more so South Florida, the temps can really be tough in traffic to say the least. Add 90 more cubes and still a stock radiator, makes it more prevelent. Is it overheating? probably not as the stock fan settings do not come on till 229* on fan 1 and 235* on fan 2.
The best example I can give is my 2000 C5 Vette I owned up till last year. Forged 346 with everything and runs low 11's on street tires. Usually she would run 185-200 with the A/C on cruising or any condition. I have the stock radiator, stock fans, 160* thermostat, fans on at 185-190*F and it was an M6. I had just 3 quearts coolant with a bottle of Water Wetter and the rest distilled water.
I was in Miami for a wedding and got caught in stopped traffic on I-95 around 5PM. Outside temp was 98*, heat off the road was probably 140-150* or better, hot exhaust from the car in front of me heading towards the radiator as well as the A/C condensor 1" in front of the stock radiator generating heat. All this had the temps running 225-230*, but no other issues. Basically it was exchanging as much heat as possible for the given situation. Was she overheating? No, just running on the hotter side of normal. Once we got rolling over 25-30MPH agin constantly the temps came back down to 200* and under.
If you were to do a larger radiator and better fans it may help, but I would not be surprised to see the higher temps still on a hot South Florida day with the A/C on in traffic. Just sometimes a part of living here. Most likely this was going on before also. You just make it the best you can make it. If she is pinging, then maybe we need to change some of the temp to timing parameters to keep her safe.
Hope this helps.
Mike Norris
I would double check what the actual temps are via scanner though you said you did in the past. The F-body coolant temp gauge is notoriously off one way or the other, but rarely right.
What it sounds like to me is somewhat normal, though not what people wnat. In Florida, and more so South Florida, the temps can really be tough in traffic to say the least. Add 90 more cubes and still a stock radiator, makes it more prevelent. Is it overheating? probably not as the stock fan settings do not come on till 229* on fan 1 and 235* on fan 2.
The best example I can give is my 2000 C5 Vette I owned up till last year. Forged 346 with everything and runs low 11's on street tires. Usually she would run 185-200 with the A/C on cruising or any condition. I have the stock radiator, stock fans, 160* thermostat, fans on at 185-190*F and it was an M6. I had just 3 quearts coolant with a bottle of Water Wetter and the rest distilled water.
I was in Miami for a wedding and got caught in stopped traffic on I-95 around 5PM. Outside temp was 98*, heat off the road was probably 140-150* or better, hot exhaust from the car in front of me heading towards the radiator as well as the A/C condensor 1" in front of the stock radiator generating heat. All this had the temps running 225-230*, but no other issues. Basically it was exchanging as much heat as possible for the given situation. Was she overheating? No, just running on the hotter side of normal. Once we got rolling over 25-30MPH agin constantly the temps came back down to 200* and under.
If you were to do a larger radiator and better fans it may help, but I would not be surprised to see the higher temps still on a hot South Florida day with the A/C on in traffic. Just sometimes a part of living here. Most likely this was going on before also. You just make it the best you can make it. If she is pinging, then maybe we need to change some of the temp to timing parameters to keep her safe.
Hope this helps.
Mike Norris
My first engine never did this and I had that engine in my car for over a year, remember, than I got the new one and the heat was right from day 1, I used my A/C every day in the summer with the first engine, the temps never went near the 210 mark. And never detonated.
I'm thinkiung my fans are not going into high or maybe like you said, they need to be set differently.
My temps have been confirmed by a scanner to be about 25-30 degrees higher than what it says on the gauge. When I drive around with the A/C "off" the temps never get near the 155 mark on the gauge. Runs perfectly and never detonates. As soon as I turn it "on" it goes right past the 210 mark. A scanner showed my temps to be around 230 degrees when right on the 210 mark. So the times it went past that mark I was probably closing in on 240 degrees or higher. When I open the hood you CANNOT put your hand on the TB, the intake, or the air lid, you will burn your hand instantly. My Hotchkis STB is hot enough to literally burn you badly. Can't hold the dipstick either. If you put your hand on the shock tower to lean on it you will fry your skin. When I drive around with the A/C off I can put my hand anywhere and its not hot at all.
The detonation when it gets near the 210 mark, not at the 210 mark yet, but just inbetween the 155 and 210 mark, is so bad it sounds like the engine is in pieces falling onto the ground. So there's no question that its getting way hotter than it ever should, something must be wrong. After its real hot and I turn the A/C "off", it cools down to below the 155 mark in a matter of a few minutes and detonation is completely gone.
I'm gonna try to get it to a dealer today to check the fans.
I'd like to just buy new aftermarket, higher flowing fans if they're available.
Thanks,
Lyle
Last edited by Quickin; 09-06-2005 at 01:21 PM.
09-06-2005, 03:20 PM
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Originally Posted by gwj
Well, to review. We have suggested the basics, like how to check if the fans actually function at both low/high settings independent of PCM commands.
But the engine was not hot yet, at least not hot enough to detonate, it ran perfectly fine. I didn't let it get any hotter.
So I have confirmed that both fans work on both settings, and they work at the same time, never separate.
I think I just need aftermarket fans and a bigger radiator. I heard the SLP radiator is junk and doesn't help at all. A couple guys around here had it put in and saw no change.
Who sells one that really works better?
Better fans?
Thanks for all the help man.
Mike Norris,
I guess the fans are coming on HIGH way before the engine gets hot, so thats good I guess. The PCM must be set OK. Maybe its the 90 extra cubes.
But its still wierd that my first 436 engine didn't have this problem at all.
Is there something during a build that can hinder/block water flow through an engine?
09-06-2005, 05:23 PM
#18
Not sure what to say as to why the first engine seemed okay and now this one is different. Basically if the engine is fine with the A/C off, I would say the engine is not the problem. Since you add the extra heat of the A/C condensor and that it begins to show, I am thinking a heat exchage issue. I would reaaly like to see the actual numbers from the PCM versus the gauge even though you say you know the discrepency in the two.
The larger radiator and better fans may help, but usually do not cure these issues. Good luck and let me know.
Mike Norris
The larger radiator and better fans may help, but usually do not cure these issues. Good luck and let me know.
Mike Norris
09-06-2005, 07:40 PM
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Originally Posted by Mike Norris
Not sure what to say as to why the first engine seemed okay and now this one is different. Basically if the engine is fine with the A/C off, I would say the engine is not the problem. Since you add the extra heat of the A/C condensor and that it begins to show, I am thinking a heat exchage issue. I would reaaly like to see the actual numbers from the PCM versus the gauge even though you say you know the discrepency in the two.
The larger radiator and better fans may help, but usually do not cure these issues. Good luck and let me know.
Mike Norris
The larger radiator and better fans may help, but usually do not cure these issues. Good luck and let me know.
Mike Norris
09-06-2005, 08:00 PM
#20
Maybe "issue" is the wrong word. More like what the cooling capabilities are for a given situation. The condensor is most likely fine.
The way I test some systems for these complaints is to park the vehicle right up close to a building wall exposed to the sun in the middle of the day as well as being on blacktop. With the car idling and the A/C on, it limits the amount of "clean air" that is able to reach the radiator. This somewhat simulates stop and go traffic, but not as extreme. If I see temps in the 220-230 range after 5-10 minutes of idling after starting at "normal" operating temps, I consider this okay to go.
I guess in the short version, there is most likely nothing wrong, but maybe the cooling system can be made better with a larger radiator and more efficient fan package. I would not sweat the temps so much, though it does not hurt to try and make it better. I would work on the tuning to address the spark knock situation as that can permanently damage the engine in a short time. Even a forged engine.
An extreme fix would be to relocate the A/C condensor and have a remote fan. That is a completely different story.
Mike Norris
The way I test some systems for these complaints is to park the vehicle right up close to a building wall exposed to the sun in the middle of the day as well as being on blacktop. With the car idling and the A/C on, it limits the amount of "clean air" that is able to reach the radiator. This somewhat simulates stop and go traffic, but not as extreme. If I see temps in the 220-230 range after 5-10 minutes of idling after starting at "normal" operating temps, I consider this okay to go.
I guess in the short version, there is most likely nothing wrong, but maybe the cooling system can be made better with a larger radiator and more efficient fan package. I would not sweat the temps so much, though it does not hurt to try and make it better. I would work on the tuning to address the spark knock situation as that can permanently damage the engine in a short time. Even a forged engine.
An extreme fix would be to relocate the A/C condensor and have a remote fan. That is a completely different story.
Mike Norris