overheating and dieing......

[hewlett2002000]

my truck just died again on me today, its getting too hot after its driven for 10 or 15 minutes. the radiator is an IL6 radiator from the original engine. and i have no shroud. im thinking im going to invest in a good 4 core radiator and electric fan. i have a 170 thermostat. why is it overheating? please help.
thanks,
John

[six4flat]

take off the bottom hose of the radiator to make sure the water is flowing free, and the check the thermostat

[Eliasj123]

I don't suggest switching to a 4 core nor a lower t-stat yet. These trucks were designed to work and stay at a certain temp right off the line. So, if it's over heating, a bigger radiator and lower t-stat may just mask the problem. There are a few things you can do and there are a few things that it can be.

There could be a leak that you can't see which is causing the over heating. Could be a stuck t-stat. Could be a bad water pump. Could be a clogged radiator or ports in the head. And for the biggie, you could have a blown head gasket or warped head.

First, check the fluid to make sure it's topped off, check the color and smell it. There shouldn't be any brown sludge or smell like gas or oil. Then, check your dip stick to make sure that it's normal. It shouldn't be brown either. If you have any of these signs, it's not looking good.....

Next, when it's cold, start it up, then hold the upper radiator hose; it should be cold. You should feel it get warm when the truck warms up. If it doesn't get warm, then you know that the cooling system is not flowing.

The t-stat is the easiest and cheapest thing to replace. You can do a flush too. They sell radiator flush kits at the auto parts, but shops do a 10 times better job at it.. Next, the water pump should be replaced if the other two don't resolve the issue.

That's a good starting point.. Let us know, then we can go from there..

Elias

[hewlett2002000]

well when i changed the intake the water ports were clogged but not terribly. the water pump could be a big possability because the truck was sitting for probably 2 years. that and the radiator is real dirty. probably a combination of all of that. im gonna replace the water pump and flush the system and all that good stuff and go from there. ill let you know how it goes.

[slepysal]

Dont over look a weak lower rad hose. make sure it isnt colasping under load.
anf flush flush flush

[martinkh]

Step 1, do a good flush.
Make sure your cap is good, and the overflow line isn't leaking, and your overflow container shouldn't leak either.

I'd go for the 4 core, and check your fan clutch. an electric fan is in itself risky, a failure can go unnoticed until your needle is pegged.

[rickf]

I had the same problem with the same setup, the small 18x18 core radiator and a sbc 350. It overheated, but didn't get over 250. WIth the thermostat out it wouldn't even heat up over 140. As a temporary solution I got a 160 thermostat and drilled a bunch of 3/16 holes around the permiter to increase flow. I also did not have a fan shroud so added an electric fan. It takes a long time to warm up, due to constant flow from mangled thermostat, but it does not overheat.

I am in process of converting to the larger 17x25 radiator now.

My engine was running and in use in another truck, used by a pal for a year before I got it. It was a daily driver, and had no overheating problems. Since the whole engine was swapped unchanged, I did not suspect the problem to be anything in the engine. The only thing different was the radiator. I did replace the thermostat first, though, just in case. It made no difference.

Someone mentioned a "bad" waterpump. I have to ask, other than developing a leak or bearings wearing out, what can possibly go wrong with these water pumps? They are merely an impeller, no? No ball checks or other valves of any sort in any auto water pump I have ever seen. Can impellers fall off? If they don't leak and don't rattle or squeak, how could they possibly not pump?

[hewlett2002000]

thank you, that helped me alot. im just going to invest in a bigger radiator. i think that will stop the problem. if not i needed it anyway, i got 2 cans of alumaseal in my radiator. anyways, ill let you know how it works out. thanks for the help.

[slorio]

I would also check the ignition timing before investing in a radiator. If the timing is too far advanced, it will cause the engine to run hot.
regards,
Steve

[hewlett2002000]

lol, well i cant get it perfect because that metal plate above the harmonic balancer is broke off. i still dont know what im gonna do bout that. but it is pretty close, im pretty sure thats not whats wrong. thanks yall

[hewlett2002000]

ok yall i found out i had a blown head gasket. me and a buddy fixed it and its still overheating!!!!!!!!!! i boiled the thermostat and it seems to be working fine. a buddy just gave me a big radiator from his 65 that has a very small pinhole leak that he couldent get sealed, so im gonna stick that in there and see if it still runs hot, and if it doesent ill buy a new radiator. if it still overheats then ill buy a new water pump. and if it still overheats then i give up.

[six4flat]

make sure the head or block didnt crack when it was running hot befor, that happened to me when i had my impala didnt know the head was cracked until after

[Sillyoldman]

Im really not awake yet. I thought the title said "Overeating and Dieting". I going out for coffee.

[Eliasj123]

Originally Posted by hewlett2002000

ok yall i found out i had a blown head gasket. me and a buddy fixed it and its still overheating!!!!!!!!!! i boiled the thermostat and it seems to be working fine. a buddy just gave me a big radiator from his 65 that has a very small pinhole leak that he couldent get sealed, so im gonna stick that in there and see if it still runs hot, and if it doesent ill buy a new radiator. if it still overheats then ill buy a new water pump. and if it still overheats then i give up.

Wouldn't it be easier to have replaced the water pump first?? Just like six4flat said, you may have a cracked or warped head which will cause boil over. Very rarely have I seen a blown head gasket not cause any other damage. The only time is when the person didn't torque the head down correctly..

Since you found some ports clogged and it's been sitting, have you done a major flush?? You may have to flush a few times to get all the stuff out of there.

Elias

[Bryan59EC]

The six radiator is probably not big enough.

Not enough advance can create overheating as well as too much

I once had the impeller of a NEW w/p fall off during the run in of the motor.
not funny

[Chevyboy1962]

The inline 6 radiator is too small for a sbc V8. Put in a 4 core radiator, and the engine should only run 180-190 without a fan shroud.
David