Just as the title states. Rebuilt the radiator, new core and everything, had a thermostat, now no thermostat, new hoses, new belts, new water pump and new rad cap. Nothing. Still boils over. I’m between head gaskets or rust in the cooling passages. I have some evapo-rust thermocure coming this afternoon to treat the rust. I’m concerned I’m missing some little detail that an old school olds guy would know. Any feedback is appreciated guys!
If it’s any help, there is flow, the water comes in clear (did SEVERAL coolant flushes) but comes back murky which leads me to believe the passages are all mucked up
Have you tested the functionality of the rad with a infrared thermometer gun, possibility of plugging up with crap from the block, I’m assuming this is not a new rebuild?
The radiator literally got back to me two weeks ago today. Fresh rebuild. And yes, I’ve used a heat gun on the face of the radiator, the hoses, and intake manifold. All within a few degrees of each other
Is the heater working, and does it really pour out the heat? Is the heater core at least connected? If so, have you tried bypassing it?
Spring is helpful to keep the hose from sucking closed. Is this a high mileage engine or rebuilt recently? Are there bubbles in the return water to the radiator?
Something people overlook is cooling system capacity....I had issues with the cooling my hemi in my 34 Ford....Was finally able to get a radiator that was very close to the factory capacity...
With it running from a cold start with the radiator full to the top, look in the radiator and see if you see bubbles. If you do you have a bad head gasket or cracked head.
We need more information. When does it overheat? At idle? When driving? Driving how fast? Driving in town? Driving on the highway? Does it build excessive pressure? What kind of radiator cap? Pressure type or non pressure type? What pressure is the cap rated for? What type of fan? Solid drive or clutch type? Are the belts correctly tensioned?
Further to Truckdoctor Andy’s post, is the shroud in place, correct shroud? My question about a rebuild pertained to the engine, as in correctly installed head gaskets? What kind of temp drop are you seeing across rad intake/ outlet?
@Ryan Noyes , has this Olds been like this since your purchase? I noticed you had a post regarding a rusted out frost plug earlier that you repaired. Or did this just appear after fixing the radiator?
We can pontificate forever, but without information AND a diagnostic path, it’s all just parts tossing.
He is correct and then some there if your fan is one of those tapered low resistance flex fans. The front one with the tapered blades was on my 48 for years and it flat doesn't pull enough air to write home about at an idle at a stop light. Simple things first though. Do you have the timing set correctly? I got in a hurry when I was getting ready for trip in my 51 Merc and changed the points but didn't think to check the timing and it was way late. The engine was and Olds 350R. It didn't puke coolant but ran hot.
I have an easy trick for checking for combustion gases in the coolant. Remove the radiator cap and put a cheap disposable nitrile glove over the inlet. Start the car, if the glove fills with air quickly, this is a positive test for gases in the coolant. If so, Solder Seal makes some good products I have used in the past with recent success on OT cars.
Are you overfilling the radiator? On older cars you have to leave room for the coolant to expand so you leave the level down a couple of inches in the top tank.
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