5.3 overheating on highway in TJ Wrangler
#61
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I have not yet, like most I don't want to believe the issue is as serious as a bad head gasket etc. I should pick up a test kit and check it though, would eliminate another possible cause.
#62
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Just a thought. I'm doing an LSx swap is a C3 Corvette. The heater hose bibs shoot out right where the back of the upper control arm is located, so cloase in fact, there is not way to connect them. SO I thought I'd just plug them, as NOBODY ever needs heat in a C3, right? Well, after researching the design of the LS water pump, it appears that the thermostat is controlled via water RETURNING from the heater core, dumping it right on top of the thermostat. Point in case is it seems the water pump must continuously recirculate through the heater core for proper thermostat operation. Also, MOST C3's had a factory manual water control valve placed inline leading into the heater core...to help prevent from baking in an already rather warm environment.
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me
![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
#63
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Just a thought. I'm doing an LSx swap is a C3 Corvette. The heater hose bibs shoot out right where the back of the upper control arm is located, so cloase in fact, there is not way to connect them. SO I thought I'd just plug them, as NOBODY ever needs heat in a C3, right? Well, after researching the design of the LS water pump, it appears that the thermostat is controlled via water RETURNING from the heater core, dumping it right on top of the thermostat. Point in case is it seems the water pump must continuously recirculate through the heater core for proper thermostat operation. Also, MOST C3's had a factory manual water control valve placed inline leading into the heater core...to help prevent from baking in an already rather warm environment.
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me
![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
#64
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Just a thought. I'm doing an LSx swap is a C3 Corvette. The heater hose bibs shoot out right where the back of the upper control arm is located, so cloase in fact, there is not way to connect them. SO I thought I'd just plug them, as NOBODY ever needs heat in a C3, right? Well, after researching the design of the LS water pump, it appears that the thermostat is controlled via water RETURNING from the heater core, dumping it right on top of the thermostat. Point in case is it seems the water pump must continuously recirculate through the heater core for proper thermostat operation. Also, MOST C3's had a factory manual water control valve placed inline leading into the heater core...to help prevent from baking in an already rather warm environment.
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me
![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
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#65
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Just a thought. I'm doing an LSx swap is a C3 Corvette. The heater hose bibs shoot out right where the back of the upper control arm is located, so cloase in fact, there is not way to connect them. SO I thought I'd just plug them, as NOBODY ever needs heat in a C3, right? Well, after researching the design of the LS water pump, it appears that the thermostat is controlled via water RETURNING from the heater core, dumping it right on top of the thermostat. Point in case is it seems the water pump must continuously recirculate through the heater core for proper thermostat operation. Also, MOST C3's had a factory manual water control valve placed inline leading into the heater core...to help prevent from baking in an already rather warm environment.
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
This all said, I wish someone would prove me wrong, as a simple pipe plugs would be the easiest solution for me
![Cry](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_cry.gif)
Andy1
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I fought cooling issues with my turbo ls fox body. It has a front mount intercooler that blocks a lot of the air to the radiator and all the exhaust is under the hood for the turbo so it gets hot under the hood. Here's how I solved my problem. I bought a griffin 31x16 dual pass radiator, flow cooler water pump and my radiator hoses are steel braided -16an I also gutted the thermostat and plugged the water pump bypass with a 1 1/4 freeze plug with a 1/4 inch hole drilled in it. Some say gutted thermostat makes LS run hot but with my small radiator hoses I needed all the flow I could get. Before all this with a smaller radiator,160 thermostat and stock pump I would be at 220 and climbing down the interstate in no time now I idel in traffic at 205 and run down the interstate at 190-195. I also run low profile electric fans. I also run holley hp efi and the supplied Bosch o2 sensor was not very accurate and was throwing my fuel tables off after swapping to a NTK sensor and letting fuel tables relearn temps dropped 10 degrees. I know your not running holley efi but the thing I'm getting at is a bad tune will make it run hot. Maybe some of this will be helpful.
#67
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Was able to do a couple things today...
I drained the coolant system and replaced the thermostat with a new one. Before installing I added four .150 holes in the outer ring of the tstat. I also wired in a somewhat temporary LED light to check fan function at speed.
Warm up time is a bit slower possibly but not noticeable. I was able to run down the highway but not at high load for a sustained amount of time, max temp I saw was 214 under short periods of higher load, seemed to cruise at 208 or so. This is about 5 degrees lower overall from the past test...
I verified the fan DOES run on the highway at all speeds up to 70 mph and probably beyond, it does not shut off once you hit a certain speed. Not exactly sure what to think here but from what some have posted in this thread the fan should shut off once you reach a certain speed. I know I am running a single fan and factory there are dual fans, not sure if the way the fan is set-up (fan 1 or fan 2) is affecting this, will have to do more research...
I verified the fan does turn on at 210 no matter what, however what I found odd was that it seemed to shut off at different temps. It would shut off at 200 most of the time but just idling in the driveway it didn't shut off until almost 185. Again, not sure what to do with this info yet...
Overall not 100% sure if the tstat change made a difference or if coolant flow is an issue, will have to do a higher load test to verify.
I do have a lower profile winch on order to hopefully open up some grill space for airflow. I also plan on relocation the trans cooler but that is a larger projects that I still need to get parts for.
Anyone have thoughts based on the above?
I drained the coolant system and replaced the thermostat with a new one. Before installing I added four .150 holes in the outer ring of the tstat. I also wired in a somewhat temporary LED light to check fan function at speed.
Warm up time is a bit slower possibly but not noticeable. I was able to run down the highway but not at high load for a sustained amount of time, max temp I saw was 214 under short periods of higher load, seemed to cruise at 208 or so. This is about 5 degrees lower overall from the past test...
I verified the fan DOES run on the highway at all speeds up to 70 mph and probably beyond, it does not shut off once you hit a certain speed. Not exactly sure what to think here but from what some have posted in this thread the fan should shut off once you reach a certain speed. I know I am running a single fan and factory there are dual fans, not sure if the way the fan is set-up (fan 1 or fan 2) is affecting this, will have to do more research...
I verified the fan does turn on at 210 no matter what, however what I found odd was that it seemed to shut off at different temps. It would shut off at 200 most of the time but just idling in the driveway it didn't shut off until almost 185. Again, not sure what to do with this info yet...
Overall not 100% sure if the tstat change made a difference or if coolant flow is an issue, will have to do a higher load test to verify.
I do have a lower profile winch on order to hopefully open up some grill space for airflow. I also plan on relocation the trans cooler but that is a larger projects that I still need to get parts for.
Anyone have thoughts based on the above?
#69
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See if you can get the fans to come on sooner, like about 185* or so. You can do this by either a program, or installing a temp sensor that will turn the fans on. It's possible that the temp is too high before it gets a chance to cool. I would run a shroud, running more fans may not be the answer. You need to find out how much CFM the existing fan is. You could go with a higher CFM single fan or dual fans. I ran dual as seen from the images I posted. One turned on at 180*, the other at 190*. I am not that familiar with your engine bay, as far as air pushing though it. I can tell you that in my '96 Imp SS, it was stuffed in. Inter cooler, trans cooler, condenser, radiator. Plus the heat from the supercharger itself. The radiator is a BeCool that supports up to 900 hp if I remember correctly. There is not a lot of clearance under the hood height either.
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#71
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Thanks for the replies everyone, much appreciated! Another long post so bear with me...
Does anyone have an example of the air dam that has been referenced? Because this is a heavily modified Jeep with large tires, hydro assist steering, etc, its hard to think I can add an air dam as has been mentioned. There is the factory rubber under the radiator but adding an air dam is close to impossible unless I am missing something...which is very possible.
I can certainly change the fan settings and have the fan turn on sooner. What is in my head however is that all this would do would delay the same issues I am having. Here's my logic, using the factory tstat it opens at 187 and is probably not fully open until 195 or so. Lets say the fan turns on at 195 instead of 210. Once on the highway the fan will turn on, continue to run, and eventually the same max temp will be reached. If my logic is wrong here I would love to know because this helping would be a huge benefit.
From earlier test of pulling the fan fuse and having temps get to 230+ I am afraid I need the fan on at all times on the highway. This however seems incredibly backwards and I still suspect an airflow problem at higher speeds. The fan could be blocking air from going through the radiator and I am reaching max efficiency as its set-up. See info from SPAL below in regards to static pressure and CFM...
The fan is a SPAL P/N 30102082 (VA33-AP71/LL-65A 12V), and I have provided the link below. I spoke with SPAL a week or so ago and talked in detail about the application. They said the fan I have is the one needed as at higher speeds (increased static pressure) the curved blades will not impede air flow as much as a straight blade fan. Some of the CFM ratings are below, you can see more in the link...
CFM - static pressure
1918 - 0
1381 - 15
0 - 40
https://webstore.spalusa.com/content...02082_SPEC.pdf
I keep saying that I need to move the trans cooler and I plan on doing so, along with adding the shorter winch. While these two things will help I'm still not certain it will be enough...
I will try to get a couple pics and post them this week...
Thanks again to all, hopefully I can get this thing sorted out before NEXT summer
Does anyone have an example of the air dam that has been referenced? Because this is a heavily modified Jeep with large tires, hydro assist steering, etc, its hard to think I can add an air dam as has been mentioned. There is the factory rubber under the radiator but adding an air dam is close to impossible unless I am missing something...which is very possible.
I can certainly change the fan settings and have the fan turn on sooner. What is in my head however is that all this would do would delay the same issues I am having. Here's my logic, using the factory tstat it opens at 187 and is probably not fully open until 195 or so. Lets say the fan turns on at 195 instead of 210. Once on the highway the fan will turn on, continue to run, and eventually the same max temp will be reached. If my logic is wrong here I would love to know because this helping would be a huge benefit.
From earlier test of pulling the fan fuse and having temps get to 230+ I am afraid I need the fan on at all times on the highway. This however seems incredibly backwards and I still suspect an airflow problem at higher speeds. The fan could be blocking air from going through the radiator and I am reaching max efficiency as its set-up. See info from SPAL below in regards to static pressure and CFM...
The fan is a SPAL P/N 30102082 (VA33-AP71/LL-65A 12V), and I have provided the link below. I spoke with SPAL a week or so ago and talked in detail about the application. They said the fan I have is the one needed as at higher speeds (increased static pressure) the curved blades will not impede air flow as much as a straight blade fan. Some of the CFM ratings are below, you can see more in the link...
CFM - static pressure
1918 - 0
1381 - 15
0 - 40
https://webstore.spalusa.com/content...02082_SPEC.pdf
I keep saying that I need to move the trans cooler and I plan on doing so, along with adding the shorter winch. While these two things will help I'm still not certain it will be enough...
I will try to get a couple pics and post them this week...
Thanks again to all, hopefully I can get this thing sorted out before NEXT summer
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#72
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I built a chin spoiler for a '85 Camaro that I built for Silver State racing years ago. It was intended to keep the nose down to the ground. I almost flipped the car nearing the 185 mph mark one day. I used three turn buckles, a hinge, either a 1/8 or 3/16 sheet of Aluminum. I could adjust the angle to suit my needs. You could do the very same thing to grab air and direct it into the engine bay for air flow & cooling.
I mounted it to the lower radiator support, you will have to find a way to mount it more rearward for your application, or add another sheet of aluminum to the other side of the hinge and add air flow holes to it.
The hinge is self explanatory, one end of the turn buckles will need to be mounted to a non-moving surface. The other end (depending on length) were mounted about 1/2 inch from the bottom of the aluminum sheet. Think along the lines of a Pro-Street, NASCAR wing but mounted up-side down and in the front. Yours won't need to be as big or bulky, I would imagine now more than 20" wide and 6" tall at the most. You can go to Lowes and get cheap turnbuckles for 1/4"or less threads. That should be more than strong enough to take the wind force.
I mounted it to the lower radiator support, you will have to find a way to mount it more rearward for your application, or add another sheet of aluminum to the other side of the hinge and add air flow holes to it.
The hinge is self explanatory, one end of the turn buckles will need to be mounted to a non-moving surface. The other end (depending on length) were mounted about 1/2 inch from the bottom of the aluminum sheet. Think along the lines of a Pro-Street, NASCAR wing but mounted up-side down and in the front. Yours won't need to be as big or bulky, I would imagine now more than 20" wide and 6" tall at the most. You can go to Lowes and get cheap turnbuckles for 1/4"or less threads. That should be more than strong enough to take the wind force.
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Last edited by Avarookie; 08-04-2014 at 05:32 PM.
#73
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Avarookie thanks a ton for the explanation. Unfortunately I might as well be dealing with a space shuttle in terms of adding an air dam. The bottom of the front bumper is 27" off the ground and there is a one ton axle, hydro assist steering, steering linkage, etc, all in the way. I am all about trying to increase airflow through the radiator and will look into what I can do for my set-up. I do want to get more air through the radiator and out of the engine compartment. The smaller winch, relocating the trans cooler, and adding some mesh to the inner fenders is my current plan.
I am also considering going to a higher CFM fan as the SPAL, while decent, isn't the best option I don't think. I have read about the following other options which I am researching now...Taurus, Contour, Mark VIII, and others. One that has peaked my interest is from a WJ Jeep Grand Cherokee, it will fit in the stock Jeep fan shroud and pulls a ton of air.
I do think the Jeep is drivable as is, my temps have come down some from when I started this process. I will make changes as time will allow and hopefully in the end I am never seeing higher than 220.
I still find it interesting that factory LS cars have the high fan come on at 235 or so, makes me wonder how much of an issue some of us Jeep guys really have. The vehicle is shaped like a brick, has big tires, and weighs two plus tons. Most of the people I have spoken to with V8 swaps in Jeeps have the exact same issues...I just happen to see it more being at 5K+ elevation with hills etc. People in the flatlands have more air for the engine to breathe and less hills.
One of my main remaining questions is still in regards to fan function at speed. I know there are lots of different scenarios (a/c, IAT, fuel trims) but SHOULD the fan run on the highway at say 65 mph with a/c off, fuel trims good, and good IAT??? I know there may not be a solid answer but everyone says you don't need the fan...yet I seem to.
Thanks again to all!
I am also considering going to a higher CFM fan as the SPAL, while decent, isn't the best option I don't think. I have read about the following other options which I am researching now...Taurus, Contour, Mark VIII, and others. One that has peaked my interest is from a WJ Jeep Grand Cherokee, it will fit in the stock Jeep fan shroud and pulls a ton of air.
I do think the Jeep is drivable as is, my temps have come down some from when I started this process. I will make changes as time will allow and hopefully in the end I am never seeing higher than 220.
I still find it interesting that factory LS cars have the high fan come on at 235 or so, makes me wonder how much of an issue some of us Jeep guys really have. The vehicle is shaped like a brick, has big tires, and weighs two plus tons. Most of the people I have spoken to with V8 swaps in Jeeps have the exact same issues...I just happen to see it more being at 5K+ elevation with hills etc. People in the flatlands have more air for the engine to breathe and less hills.
One of my main remaining questions is still in regards to fan function at speed. I know there are lots of different scenarios (a/c, IAT, fuel trims) but SHOULD the fan run on the highway at say 65 mph with a/c off, fuel trims good, and good IAT??? I know there may not be a solid answer but everyone says you don't need the fan...yet I seem to.
Thanks again to all!
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Jeep thing, apparently you do have the latest Novak radiator/shroud.
I emailed the rep I've been speaking to about mine since my shroud was supposed to have been sent beginning of July. I was told they're sending me a new radiator design and a new fan shroud. Supposedly it's about a week out.
Once it's here I'll post some pics so you can compare it to what you've got.
Personally I found a new mark viii fan and plan on making it work. Completely unscientific but when I hooked it up to an old battery I had it literally blew itself away from where I had placed it.
The Spal doesn't even compare. Well atleast the one I've got.
I emailed the rep I've been speaking to about mine since my shroud was supposed to have been sent beginning of July. I was told they're sending me a new radiator design and a new fan shroud. Supposedly it's about a week out.
Once it's here I'll post some pics so you can compare it to what you've got.
Personally I found a new mark viii fan and plan on making it work. Completely unscientific but when I hooked it up to an old battery I had it literally blew itself away from where I had placed it.
The Spal doesn't even compare. Well atleast the one I've got.
#76
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Punisher8738 thanks for the post, from what I know I have the most recent rad and shroud. I do know they are working on another shroud with rubber flaps instead of the metal doors with springs. Post up when you receive yours as I'm interested to hear what you get.
I am not sure if they have ever changed which SPAL fan they used, I don't think so though. I have heard the Mark VIII moves a lot of air but is deep and hard to fit between the motor and radiator. I am going to look into Chrysler part number CBG4F250 which is for an 02' Jeep Grand Cherokee. It can be used in the stock 4.0L shroud and fits from what I have read. Its not as popular I don't think but if it moves more air than the SPAL its an upgrade.
While I think SPAL makes great products I don't know if they are the right answer for what our needs are...
I am not sure if they have ever changed which SPAL fan they used, I don't think so though. I have heard the Mark VIII moves a lot of air but is deep and hard to fit between the motor and radiator. I am going to look into Chrysler part number CBG4F250 which is for an 02' Jeep Grand Cherokee. It can be used in the stock 4.0L shroud and fits from what I have read. Its not as popular I don't think but if it moves more air than the SPAL its an upgrade.
While I think SPAL makes great products I don't know if they are the right answer for what our needs are...
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The only mod I may have to do is either trim off the threaded portion of my truck waterpump or go to a car pump so the clearance is tight but I've got the room there without trimming the lincoln shroud.
Although I'll he going with the lincoln you've got my curiosity now regarding the WJ fan. I'll have to take a look at my wife's 04.
Although I'll he going with the lincoln you've got my curiosity now regarding the WJ fan. I'll have to take a look at my wife's 04.
#78
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Punisher8738 post up the part number from your SPAL fan, mine is below...
VA33-AP71/LL-65A 12 v - on the actual fan
30102082 - P/N from SPAL
The WJ fan I posted the part number from above is from a recall that didn't affect as new as 04' vehicles. I cant find a CFM rating for it yet but am still looking. Have you verified if your fan runs on the highway? That is still one of the confusing things for me, I hope a better fan would help at high speed as well...
VA33-AP71/LL-65A 12 v - on the actual fan
30102082 - P/N from SPAL
The WJ fan I posted the part number from above is from a recall that didn't affect as new as 04' vehicles. I cant find a CFM rating for it yet but am still looking. Have you verified if your fan runs on the highway? That is still one of the confusing things for me, I hope a better fan would help at high speed as well...
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Yeah I have the same fan. The high output one they list is the AP91 model. Novak sent me their single core radiator which I was first told the more efficient one, but now am being sent a new one. I'll wait and see what the new one specs at. Yes, my fan runs on the highway. Since I have an 04 truck PCM that originally had a mechanical fan, I didn't have programming for electric. I'm using a dakota digital pac-2750 controller. I've got a kill switch and a secondary circuit/toggle just incase I blow a fuse. I have my temps set to come on at 205 and off at 195. If I turn off the fan on the highway it warms up. My problem I'm pretty sure is with air damming in the novak shroud and the fact I have a single core radiator. So besides the fan, new radiator and possibly an evans cooling water pump, I'm also going to add the poison spyder full hood louver panel to my jeep. I've currently got the gen right panels but the psc looks like it would vent more heat. Hopefully I'll have it back on the road while the temps are still holding around 100 here.
Last edited by Punisher8738; 08-06-2014 at 03:24 PM.
#80
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Punisher8738 I had the exact same thoughts in regards to the radiator and shroud and unfortunately it didn't make the difference I was hoping for...
I currently have the exact set-up you will be changing to and while I do think I am down a few degrees its not enough. I have the newer 2 core Novak radiator, shroud with doors (doors now removed), and large hood vent panel.
I also think the shroud hinders airflow and Novak has said the same, and proved it by changing the shroud multiple times now. I am tempted to remove the shroud all together and try that but after removing the shroud doors it does take a bit longer to cool down at lower speed (still reasonable though so leaving them off).
I think addressing the fan is the next step and it sounds like we both have an idea of how to do so. The Cherokee fan is supposedly rated at 4,000 CFM, much higher than the 1918 CFM of the SPAL. I know that is at 0 static pressure but I'm hoping it will help...
I currently have the exact set-up you will be changing to and while I do think I am down a few degrees its not enough. I have the newer 2 core Novak radiator, shroud with doors (doors now removed), and large hood vent panel.
I also think the shroud hinders airflow and Novak has said the same, and proved it by changing the shroud multiple times now. I am tempted to remove the shroud all together and try that but after removing the shroud doors it does take a bit longer to cool down at lower speed (still reasonable though so leaving them off).
I think addressing the fan is the next step and it sounds like we both have an idea of how to do so. The Cherokee fan is supposedly rated at 4,000 CFM, much higher than the 1918 CFM of the SPAL. I know that is at 0 static pressure but I'm hoping it will help...