[Solved] 2000 Yukon XL high operating temp

[ryanguy426]

That fan clutch sounds just fine. The radiator not so much for air flow. Pics? How much area on the radiator, front and back, has bent fins?

I'll take some pictures when it's light tomorrow. The front of the radiator isn't so bad, but the back of the radiator, if you divide the radiator into quarters horizontally (lengthwise left to right), most of the bottom quarter is essentially bent. There's a lot of large patches of bent fins in other parts of the radiator as well. Not sure how well it will show up on my camera but I will try.

Here is a poorly drawn example of what I'm talking about until I can take a picture tomorrow. The spots colored red are where a majority of the bending is on that bottom section.

 

[treehan77]

Highly doubt bent fins are the cause of overheating, but possible u guess. Pressure test stop guessing.

 

[OR VietVet]

I think it is a combination. The fin air flow is important and is way overlooked a lot because it is "out of sight and out of mind". While it may not be the cause, I think the thermostat is the biggest culprit, it is still something that needs addressed when found. I will take a 1-2 degree difference in temp reading any day for a little bit of work. It also helps the condenser to dissipate heat as well with a free flow of air in that area instead of air turbulence getting stopped up and finding a different path for air release thru the fins.

 

[afpj]

Like treehan77 said goto AutoZone etc and "borrow" a pressure tester. You pay a downpayment (to encourage you to return it) Will you get all your money back when you actually return it. Therefore monetary cost is zero in the end. Not sure what you mean by you cannot afford to borrow a pressure tester, unless you don't have those types of stores in your neck of the woods.

 

[ryanguy426]

Like treehan77 said goto AutoZone etc and "borrow" a pressure tester. You pay a downpayment (to encourage you to return it) Will you get all your money back when you actually return it. Therefore monetary cost is zero in the end. Not sure what you mean by you cannot afford to borrow a pressure tester, unless you don't have those types of stores in your neck of the woods.

I mean I literally don't have the money right now until I get paid...living paycheck to paycheck. Spent all my money on doing the fuel pump. Money I have to my name is $0 until I'm paid, so I'm looking at other things I can do until then like cleaning the radiator. I know they give the money back, but I have to have money to give them in the first place...

 

[OR VietVet]

I get the money problem, we have all been there. If you have a c/c the parts store will run that and credit back just like handing you cash. Do not assume what I just said is gospel. Ask the parts guy who is helping you before you leap.

 

[ryanguy426]

My friend let me borrow money to get the tester.

I pumped it up to 16psi and my top radiator hose started dripping from the water pump. Reseated it and pumped back to 16psi. No drips anymore, and over the course of 30 minutes it went down from 16psi to 15psi and held. No visible leaks on the ground at this point. Inspected the other hoses, haven't found any liquid near them.

 

[Fless]

Nice! And your friend deserves a great big thank you!

 

[rockola1971]

But is it still overheating? I thought I read that its running 230deg even when filled with coolant. Make sure you dont have any air trapped in the coolant system!

 

[OR VietVet]

I think the thermostat and the drip repair will be a 95% fix but I would still get a clear air flow for that radiator. IMO.