I can't keep it cool
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Teching In
Joined: Mar 2014
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From: Phoenix
I can't keep it cool Please help, I've looked through many posts but I can't find an answer to my cooling issue. I bought the truck with a ls1/243 heads, mid lift cam and little did I know warped heads from overheating! I thought it was due to a bad rad cap and a malfunctioning temp gauge. So I pulled the heads, decked them, new rad cap, sweet aluminum cooling hoses and called it a day. I pressure tested the system and its been running at about 230 all winter. I opened it up on the freeway today to kill a F150 and got home and I heard the boiling in the radiator as soon as I got out! Back to the same problem. I figured it was running a little hot because of the old radiator that was probably made for the 350 that was originally in it. I can hear a distinct hissing from the area under the throttle body but can't pin point it. I sprayed wd40 all around the area hoping to hear bubbles and locate the leak. Could it possibly be a water pump bearing that when under heat and pressure gets leaky? There are no visible leaks which is making this difficult. Should I replace the water pump before I do anything else? Also, my starter got heat sink and the truck has to cool down before the starter will work again. Will a high end starter fix that problem? Thanks again, ya'll always step up when I have questions.
Thread Starter
Teching In
Joined: Mar 2014
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From: Phoenix
It's a 180 therm, dex 50/50, fan shroud yes for dual electric fan both come one at same time. It's a new auto meter water gauge and its hooked up to the head on back passenger side. I live in Phoenix and it's starting to get warm. It was starting to move up to 250 in my driveway then I shut it down. the boiling sounds were very audible and the hissing leak was pretty noticeable too. Now I'm assuming it's loosing pressure and that's why its boiling. I'm not that good with cooling systems tho
I know it sounds stupid but have you checked to make sure the fans are mounted/wired correctly, I fixed a car last year that had fans mounted on the inside of the radiator(engine side) trying to push air to the front. Worked much better after I wired them to pull air in.
To answer your question on the water pump. They usually fail and leak when hot or cold, Although they will leak faster if pressure builds up. 250* is pretty hot and likely going to boil no matter what, You also have to remember that when you shut it off the water is no longer circulating so it can get localized hot spots (heads are still trying to dissipate heat) so it will continue to rise for a few minutes. (That's why you should leave it running and cool it down of possible.)
Another possible cause is the tune. If it's running to lean or the timing is off it can cause overheating.
To answer your question on the water pump. They usually fail and leak when hot or cold, Although they will leak faster if pressure builds up. 250* is pretty hot and likely going to boil no matter what, You also have to remember that when you shut it off the water is no longer circulating so it can get localized hot spots (heads are still trying to dissipate heat) so it will continue to rise for a few minutes. (That's why you should leave it running and cool it down of possible.)
Another possible cause is the tune. If it's running to lean or the timing is off it can cause overheating.
Thread Starter
Teching In
Joined: Mar 2014
Posts: 31
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From: Phoenix
I know it sounds stupid but have you checked to make sure the fans are mounted/wired correctly, I fixed a car last year that had fans mounted on the inside of the radiator(engine side) trying to push air to the front. Worked much better after I wired them to pull air in.
To answer your question on the water pump. They usually fail and leak when hot or cold, Although they will leak faster if pressure builds up. 250* is pretty hot and likely going to boil no matter what, You also have to remember that when you shut it off the water is no longer circulating so it can get localized hot spots (heads are still trying to dissipate heat) so it will continue to rise for a few minutes. (That's why you should leave it running and cool it down of possible.)
Another possible cause is the tune. If it's running to lean or the timing is off it can cause overheating.
To answer your question on the water pump. They usually fail and leak when hot or cold, Although they will leak faster if pressure builds up. 250* is pretty hot and likely going to boil no matter what, You also have to remember that when you shut it off the water is no longer circulating so it can get localized hot spots (heads are still trying to dissipate heat) so it will continue to rise for a few minutes. (That's why you should leave it running and cool it down of possible.)
Another possible cause is the tune. If it's running to lean or the timing is off it can cause overheating.
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Thread Starter
Teching In
Joined: Mar 2014
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From: Phoenix
I was searching for rads, Rnd fabrication looks pretty good. Any recommendations? The eBay radiators scare me, they are cheap but I don't want a cheap *** made radiator.
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Verdad Gallardo I'm actually surprised that it runs well on the stock tune with all those mods either that or someone else tuned it before you got it. It wouldn't hurt to see what the afr is.
There are actually quite a few cheap radiators on ebay that are built pretty well.
I know a few people that have used them and a bunch of people 0n another forum have used them when putting an LS1 in S10's.
There are actually quite a few cheap radiators on ebay that are built pretty well.
I know a few people that have used them and a bunch of people 0n another forum have used them when putting an LS1 in S10's.
Please help, I've looked through many posts but I can't find an answer to my cooling issue. I bought the truck with a ls1/243 heads, mid lift cam and little did I know warped heads from overheating! I thought it was due to a bad rad cap and a malfunctioning temp gauge. So I pulled the heads, decked them, new rad cap, sweet aluminum cooling hoses and called it a day. I pressure tested the system and its been running at about 230 all winter. I opened it up on the freeway today to kill a F150 and got home and I heard the boiling in the radiator as soon as I got out! Back to the same problem. I figured it was running a little hot because of the old radiator that was probably made for the 350 that was originally in it. I can hear a distinct hissing from the area under the throttle body but can't pin point it. I sprayed wd40 all around the area hoping to hear bubbles and locate the leak. Could it possibly be a water pump bearing that when under heat and pressure gets leaky? There are no visible leaks which is making this difficult. Should I replace the water pump before I do anything else? Also, my starter got heat sink and the truck has to cool down before the starter will work again. Will a high end starter fix that problem? Thanks again, ya'll always step up when I have questions.
For the starter issue....simply get a thin piece of sheet metal and mount it inbetween the starter and header pipes. Make sure you don't lay the sheet metal against the starter though.....leave a littler space for air flow......but so it won't get direct radiant heat from the header pipes.
Also....could have a warped deck on the block.....possibly.
.
Jayred,
Also, since its an LSx implant into a truck......the factory radiator and factory shroud attached to the radiator are a very important part of the cooling efficiency.
Is it a custom cooling set up.....or do you have the factory radiator/fan shroud in the truck...? Without that shroud, it can cause endless cooling problems......
I see some custom set ups work.....even some without the shroud....but its really important to have air sucked through the shroud and blasted across the entire surface of the radiator.....without the shroud properly attached the air flow gets lost.
.
Also, since its an LSx implant into a truck......the factory radiator and factory shroud attached to the radiator are a very important part of the cooling efficiency.
Is it a custom cooling set up.....or do you have the factory radiator/fan shroud in the truck...? Without that shroud, it can cause endless cooling problems......
I see some custom set ups work.....even some without the shroud....but its really important to have air sucked through the shroud and blasted across the entire surface of the radiator.....without the shroud properly attached the air flow gets lost.
.
This time of year, when we see these comments, the culprit is usually airflow as others above have pointed out. ^ If the temperature is spiking when you aren't moving, then I'd also be suspicious of how the fans are flowing air over what you have.
(If you maintain the proper temperature while moving, the radiator you have now should be fine - that may not be the case as it gets hotter.)
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I ran into something like this and I found one of the water pump gaskets was leaking. Wasn't obvious either but the car ran hot and would boil when you shut it off hot. Replaced the water pump gaskets and all the freakiness went bye bye.......
Thread Starter
Teching In
Joined: Mar 2014
Posts: 31
Likes: 0
From: Phoenix
This time of year, when we see these comments, the culprit is usually airflow as others above have pointed out. ^ If the temperature is spiking when you aren't moving, then I'd also be suspicious of how the fans are flowing air over what you have.
(If you maintain the proper temperature while moving, the radiator you have now should be fine - that may not be the case as it gets hotter.)
(If you maintain the proper temperature while moving, the radiator you have now should be fine - that may not be the case as it gets hotter.)