Beav

Hey guys I just traded for this es300 and I've been having an overheating issue. I noticed a big crack in the radiator so I replaced that with new as well as the thermostat. The timing belt and water pump have been done within a few thousand miles. After changing the radiator I drove the car for about 5 miles and on the way back it started getting hot. I thought maybe there was air in the system so I burped what I could and refilled. After another drive it was still getting hot, this is the point at which I changed the thermostat. It's late now and tomorrow I'm going to try another burp and see if that helps, any other ideas? Fan seems to be working properly and changing speeds fine. Help!

mdbrown

If you aren't losing any coolant then I'd venture a guess that there's an air pocket in there.

Beav

That's what I've been thinking also. It didn't seem like the thermostat was working I didn't see the temperature drop ever like it opened. I'm not sure how to tell if the old one was bad It didnt look too different than the new except for a little residue. With the size of crack that was in the old radiator there could be a good amount of air in the system. Best way to get rid of air is running it with the cap off til it cycles?

mdbrown

Yes, start cold with the cap off and let it run. It'll be harder to see if it's cycling though since you can't look down onto the coils like you can in a conventional radiator.

LeX2K

This is the best way. By far.

Hayk

iTrader: (1)

I agree with Lexus2000, I used it for my last coolant job and it helped me a lot.

Beav

I think I have to get one of those, unfortunately nobody in town stocks them. I took the car for a drive today and it overheated again after topping it off with coolant. When it gets hot it pushes a ton of air through the reservoir and causes some spilling so it's hard to tell if theres another leak. So frustrating...

Beav

Another update, I've been letting the car idle in my driveway with the cap off now for about 20 minutes. There are still air bubbles coming up, would you guys think there is a leak or that much air in the new system? I've been cleaning up the spillage since I can't find a spill free funnel in town. Thanks again

mdbrown

Not that familiar with your car but I do know that some cars are very difficult to purge. As long as there are air bubbles you need to let it burp.

Beav

I turned on the heater, read somewhere that might burp the heater core better. I let that run a while and it cleared up some but not fully. I'll let it cool down, refill, and try another burp session. Another thing, when I let it idle that long it didn't seem to overheat at all so I would think that air is causing my problem.

Beav

I was hoping to avoid this but I'm starting to lean towards head gasket. I don't see coolant in the oil and no white smoke out of the tail pipe but air keeps bubbling through the system. Anyone in MN looking for a side job?

mdbrown

Before you go that far, go to your local auto parts store and get a block tester. It doesn't cost much but will confirm whether or not it's a head gasket issue.

LeX2K

If all you're doing is watching for bubbles through the rad cap, you will see them endlessly. This happens because the coolant expands/contracts, air will be trapped in the top part of the radiator over and over again, and you will see bubbles.

Stop wasting time and get a hold of the spill proof funnel. A block tester is something you should do as a last resort, and keep in mind the test itself is not 100% foolproof.

Beav

Update, after the car overheated last night I didn't want to deal with it. Let it sit overnight and topped it off this morning which to my surprise was maybe only a couple cups. I did buy one of those funnels today but the car hasn't overheated even on the trip that caused it yesterday. Hopefully the car burped itself! Thanks again for the help guys