Overheating

[gosaspurs]

I have a 76 K10.  With a 350 motor, Turbo 350 transmission, stock 4 core radiator, shroud and mecanical fan.  I am having an overheating problem.  When driving, the truck runs at about 190-200 degrees, but when it comes to a stop and idles for any length of time, overheating ensues.  I have had the radiator serviced recently, changed the coolant and the thermostat yet nothing seems to work.  Any other ideas??

[cooltoolguy]

check your fan clutch.  with engine off, (that is important) and cold, the fan should spin freely by hand.   with engine at operating temp, but again the engine shut off, fan should be hard to spin, if not the fan is not engaging at idle and will not move enough air through radiator.  it will ot overheat while driving because you are pushing air through the radiator

[gosaspurs]

The fan isn't a clutch fan....its a flex fan that spins whenever the motor is on.  Thanks for the thought though.  I appreciate the suggestion!

[1976Scottsdale]

Make sure your thermostat and water pump are good.  Mine weren't, and I am now building a new engine.

[Blazin]

I would sugest a water pump. i have seen the impeler break free from the shaft, and only give a prob. at temp ideling.

[gosaspurs]

I replaced the thermostat just yesterday for the second time and the water pump was replaced less than 5 thousand miles ago.  Any other suggestions??

[Lt.Del]

Still Waterpump!!!

If your fan is good, the engine blood is not beating throughout the engine effeciently, causing it to overheat.

Make sure the pressure stays high in the coolant system.  Does your resevoir have a cap on it secure, and line doesn't have holes in it?

Replace your radiator CAP lately....they do need to be replaced every so often to keep the right PSI in the system.

Only other thing is clogged ports throughout the engine---causing the coolant not to circulate correctly.

Check your PSI.  If not that, Waterpump!!

SgtDel

[1976Scottsdale]

Yes, possible waterpump failure.  I win, mine died at 2200 miles on a brand new rebuild... because of a $28 water pump, my $1500 dollar engine is dead.  Don't make my mistake.  If there is even a shred of doubt in your mind about the pump, replace it.

[Lt.Del]

When I installed my 383 stroker I made sure I put a high-vloume pump on it. I paid $89.00 for a NAPA high quality pump, after all, it is the heart of your new engine. If you pump fails, hopefully you aren't far from home and you catch it in time.

SgtDel
www.delbridge.net