overheating

[stevens]

Just got a new clutch fan and threomstat and I cant find the problem.. Maybe a water pump?  It will get to 250' and i have to turn it off 


Chris 355 big ten

[VileZambonie]

Are you going by the gauge or is it actually overheating? Is the upper and lower radiator hose hot? Are there any cold spots in the radiator?

[stevens]

yea its by gauge and yes the hoses are hott, Ill have to check for cold spots



78 355

[DnStClr]

Any chance that the thermostat you bought isn't opening? I'd remove it and check it in a pan of hot water before going any farther.
 

[jonkmbll89]

How old is the radiator? Maybe it is stop up.

[stevens]

The thermo I had in there before was brand new also, the radiator is from a 72 so know telling how old it is but it does not look very old  no rust or leaks

somebody tould me that I might have a air bubble in my system, how would I get it out??

 

Chris 78 355 big tenn

[choptop]

The only air I have seen trapped is above the thermostat , and once it opens, the air is replaced with coolant thus the need for adding coolant once the engine warms up. Is it possible the thermostat was put in upside down. I don't want you to believe that I think you are dumb, it is the fact that I have had a brain fart in the past and put it in upside down by mistake. Just a thought. How fast does it heat up? Does it make a difference when driving or just idling. Could the fan be backwards? ( another one of mine with a flex fan)

[jonkmbll89]

I usually turn the heater on to let the coolant run throw the heater core. That helps flush out the air pockets.

[86 chevy silverado]

Where did you get the clutch fan? Something to think about, the clutch fan spins opposite on a serpentine belt set up, but they look and fit the same. I found out the hard way, I bought one brand new for my 88 3500 and overheated no matter what I did. Finally decided to get another clutch convinced it was defective, turns out he gave me the wrong one.

[stevens]

Im going to drain it this weekend, but yeah I put it in with the pointy end up and the spring down in the motor. And yes the fan is going the right way. It takes about 5mins to warm up to 210 then slowly goes up

Thanks for the help,

78 355 big ten

[VileZambonie]

you need to verify the accuracy of your gauge if it's not actually overheating.

[choptop]

It almost sounds like a blown head gasket, or cracked head. When it is running, pull the radiator cap of ( before you start it , sorry) and see if there is any bubbles in it. I have a hard time believing it would get that hot in that short of time without a major malfunction. I agree with Vile, your gauge may be goofer as well. Is it electric or mechanicl?

[stevens]

not the headgasket, motor has less than 100 miles. But Im pretty sure I found the problem. I started it with out the cap on and the water was not moving at all, so the radiator is most likely stopped up. Im going to have it cleaned or get a new one this weekend.

78 355 big ten

[stevens]

how would I check to see if my guage is working right?

[VileZambonie]

Use a laser thermometer and compare the readings to the gauge at the sender and at the thermostat housing.