I prefer to diagnose with an infrared thermometer, to check the ect and thermostat.

 

Have one just couldn’t pin point what was going one.

 

Does anybody have a radiator out that can tell me what size the orifice is inside the hose fitting for recovery tank?

 

I think you guys will like this. Found picture on the net to get idea of orifice size. Used a spent 45 shell with the primer removed and shortened to about 3/8 of an inch. Inserted it in the tank hose on the radiator end to meet flush with the radiator bib. Clamped it in place and reattached hose to radiator. Just back from test and all is back to normal.

 

glad you got it worked out

the next guy that changes that radiator will look at that and say "what the heck was this guy thinking"

Neal

 

Lol, what that mean Neal. Thinking of fixing a problem that a manufacturer missed. Sent a note to cold case radiators to let them know. They work great, looks good, but they missed this issue for cold weather.I I understand even some replacement plastic rad have this problem. Have a good evening and thanks for the input.

 

The manufacturer has a device to reduce coolant flow, to get the engine at optimal operating temperature(invented in 1934):

 

Lol, that thermostat won’t fit in the 1/2 inch inch recovery tank line.

 

I don’t think your understanding. Factory Gm radiators have a orifice back inside the Coolant line that goes from the right top of the radiator to the recovery tank. It is actually smaller than my fix. If this is not there you can never reach more that about 175 which will deliver a P0128 check engine, Low coolant temp in cold weather. Summer time is fine. That orifice is only about 1/ 16 of a inch. Mine is 1/8. Look it up Z , there is even a GM bulletin, if you don’t have this orifice, remove and replace with GM radiator. I choose all aluminum, better cooling, they just missed this cold weather issue when manufacturing this radiator.

 

I have a picture of the orifice in the factory radiator in a Silverado, which is the same for gmc, Silverado, Cadillac Escalade, and Hummer for years associated. All have the same radiator unless they don’t have oil cooler on the left side of radiator. Do you agree or disagree?