running hot

[m4]

Hello, I have a 1991 sub 4X4 auto that gets very hot when stopped in traffic.
1. Newer crate motor
2.newer factory radiator 2 core
3. thermosat
4. clutch fan turns the same as a new hayden I bought but haven't installed
5. good hoses and coolent
6. full shroud
Run @ 210 on freeway but when stopped with air on 250?

 

[4X4HIGH]

Sounds like too small of a radiator to me. I don't think i ever even seen a 2 row radiator unless it was an aluminum radiator with two 1" or 1 1/4" rows.

 

[m4]

Maybe not a two core but is the replacement for that year!

 

[Leper]

How many miles? It seems you have replaced everything but the waterpump. In rare instances I have seen the impeller on a waterpump worn down to almost nothing. The higher engine RPM causes enough cavitation to make the coolant flow through. You need to check the waterflow. I've seen a brand new t.stat not open fully and restrict flow. A large enough air pocket around the t.stat will keep it from functioning properly also. Is there anything blocking the radiator? An A/C condenser that is full of trash will keep the radiator from cooling properly.....Lemme know

 

[m4]

A new water pump was installed with crate motor. removed radiator not much between condenser and radiator. I'm going to install a four core radiator and a high flow water pump and see!

 

[Jimbo*]

Do those mods one at a time; change the radiator first and see if that solves your problem, I'd bet it will. If it still not cool enough for you, then change the water pump. You might test the t-stat in a pan of boiling water also, just to make sure it is opening like it should.
Let us know, Jimbo

 

[k20]

Seems like in the last yr or so, Ive heard of alot of t-stat problems. Even being bad right out of the box. Be and easy change for very little $$, alot less than a radiator.

 

[m4]

I'll put a new thermostat in also. Thanks all for your help

 

[dyeager535]

Or just pull it and see if the problem disappears or changes.

Also, sure the gauge is reading correct? (with the 40* difference in AC vs. non-AC, I say there is a real problem though)

 

[m4]

I installed a high flow Edelbrock water pump, new clutch fan. Four core radiator that I ordered is to big, not sure what I going to do with it. I broke off flush one of the thermostat housing bolts, man they were tight. So now I need to drill out the bolt.