Outer Limits 4x4 Board

Hi guys, just a quik question, wondering if anyone has come across the situation..

I have a 91 Sierra, softtop, And it is constantlly overheating...

Here are the things that i have checked and done...

1) Flushed radiator, and added new coolant.
2) Checked timing..
3) pulled complete cooling system out, and flushed and cleaned.
4) new water pump.
5) pulled radiator out and made sure it wasnt blocked, al ok.
6) after all this i started the engine with the radiator cap off and the thermostat removed and there was no flow through the the top tank..
7)everything flows well when its apart, had the hose goin through the engine, flowed fine.

After all this i have no idea what to do now..

One guy suggested that the head gasket could be on upside down..

Any thoughts will be appreciated..

Thanx.

Is the fan working?

My bro's 80 series was overheating because of a worn fan clutch.

Yeah, also checked that, the fan is good, and its on the right way...

Get a mechanic to check the CO2 levels in youre cooling system, you could have a cracked head as one possibility.

my zook had this problem we tryed every thing couldent work it out. i just got another motor problem solved

did you make sure that the radiator wasn't blocked by pulling the top and bottom tanks off and reaming the core?

Does it have a fan shroud? These often go missing as they tend to get discarded/broken when clumsy people are working on the cooling system/fanbelt.

If it doesn't have one, get one on it ASAP. It makes a huge difference.

I don't think no visible flow in the top tank is in itself indicative of a problem.

Steve.

have you checked the oil?

Get a TeeKay test done, this is a test that will indicate if there are any exhaust gasses in the cooling system. Do the hoses go very hard when it overheats? Is the system holding pressure? What condition is the radiator cap in, have you tried another one. Any cooling system leaks?

Layto....

c0rrupt wrote:Hi guys, just a quik question, wondering if anyone has come across the situation..

I have a 91 Sierra, softtop, And it is constantlly overheating...

Here are the things that i have checked and done...

1) Flushed radiator, and added new coolant.
2) Checked timing..
3) pulled complete cooling system out, and flushed and cleaned.
4) new water pump.
5) pulled radiator out and made sure it wasnt blocked, al ok.
6) after all this i started the engine with the radiator cap off and the thermostat removed and there was no flow through the the top tank..
7)everything flows well when its apart, had the hose goin through the engine, flowed fine.

After all this i have no idea what to do now..

One guy suggested that the head gasket could be on upside down..

Any thoughts will be appreciated..

Thanx.

Blocked or stuffed radiator?? or head gasket

Eff

faulty gauge or sensor?

have you tried using a lazer thermometer to check if it really is overheating?

you could also check where it is hot / cold - to aid in analysis.

greg wrote:faulty gauge or sensor?

have you tried using a lazer thermometer to check if it really is overheating?

you could also check where it is hot / cold - to aid in analysis.

Yes further more, how do you know its actually overheating? Ie is it boiling out of the reservoir tank?

Dan