The higher pressure cap is only a couple of pounds more. It won't do any good to get a cooler t-stat as you are already way above the opening temp of what you have.



A couple of things.



The radiator may be clogged up with plant debris, fuzz and stuff.



The t-stat, on some cars it is are very important to get one that will open the same length as OE when fully open. Some t-stat housing will seal off the bypass when the t-stat is fully open. If you get an aftermarket one this may not be the case.

 

I think ill just get an OEM thermostat to be safe. No clue how old or what brand of one is in there. Then I'll run a high pressure cap and more water than coolant and see where I stand. If that doesn't fix it I guess I need a bigger radiator.

 

I sprayed out the radiator fins last night, they didn't look too dirty. Looks like my radiator cap has been leaking slightly, there was dried white crusty's around it and the fluid was a tad low. I'll swap the cap out and hope that it's an easy fix. If that doesn't do it the thermostat will be next, with a clean fluid flush.



When I change out the fluid, can I use an air compressor to blast air through the radiator (flush out any crap that may be blocking the path?

 

^ no dont use air use a water hose and run it with high pressure thru radiator. If you think the cap is leaking change it. Top off the fluid making sure you bleed the system use new fluid you can always use it again if you change the tstat just drain in a clean pan. Having the right pressure and fluid levels goes a long way.

 

It's best to take the radiator out and spray from the engine side. Don't know how hard that is to do. I just use a water hose as most is just plant fibers like cottonwood or willow seeds.





If the cap leaks at all then there are problems as the coolant should overflow to the tank

 

Okay cool, I'll just change out the cap and hope that fixes the issue. If it doesn't I'll spray it out with high pressure water (spray through the cap location, and let it drain out where the lower hose hooks up). If it doesn't drain out freely I would suspect some blockage in the radiator and I'll replace it.



To bleed the system don't I just run the engine up to operating temp with the radiator cap off to let it purge any air? Or is there something else to bleeding it?

 

Well I guess the radiator cap wasn't leaking, just the little reservoir hose. I did notice that the bigger fan on the driver side wasn't kicking on. That was after driving for 30 minutes with the temp at 220deg. And it didn't kick on with the A/C either. When is the driver side fan supposed to turn on? How do I troubleshoot that?

 

Check fuses. Put 12V to the fan motor. It should run. Put 12V to the coil of the relay that switches power to the fan. It should run. Otherwise you're out of simple fixes.

 

Where is the coil to the fan relay? Ill go out and try to trace it out.

 

When should the fan turn on by itself? When the A/C kicks on only?