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Tue Dec 15, 2009 6:42 pm

Hey, wile trying to find an odd cooling problem today i thought i should film everything. The van came in and the owner told me it was overheating, strangely and that this was intermittent, he also told me that he loose coolant in the EX tank and he as mostly no heat in the front.... OK.

Head gasket/head crack, maybe, maybe not.

Have fun:

Ben

Tue Dec 15, 2009 7:27 pm

Merci beacoup pour le video! Tu est tres gentile a donne les temps pour nous amateurs.

Tue Dec 15, 2009 7:53 pm

That's great Ben. Thanks! I am very curious what the final fix will be.

Tue Dec 15, 2009 8:58 pm

kshbaja wrote: That's great Ben. Thanks! I am very curious what the final fix will be.

Later tonight i went back to the shop with some new test i had in my head, i found coolant in #3, plug was wet like hell. A leak down resulted in a climb of 8 psi in the coolant pressure tester.

Do you get that? Injecting compress air into the suspicious cylinder wile the coolant system was pump to 10 psi made the coolant tester gauge climb to 18 PSI, even more.

Reverse situation...

I'm perplex about those test, i can't inject air into the cylinder (lost of pressure on the coolant pressure test #1) but i can do the opposite, of course the leak down as more pressure than the coolant tester pump.

So yes, what we have here is a deteriorated head gasket.

Ben

Wed Dec 16, 2009 6:58 am

This is some really great stuff. I love being able to see your process and what tests you run. I'm eager to see the outcome.

Wed Dec 16, 2009 8:10 am

vanagonforever wrote: This is some really great stuff. I love being able to see your process and what tests you run. I'm eager to see the outcome.

This is nothing else than plumbing, some cheap tools (not even 125$) and common sense. I see so many post about overheating but i rarely see van that really overheat. Even if the vanagon as a surprising amount of coolant, hoses and tubing, it's not the space shuttle.

It can be confusing at time but with the right hinking and some basic tools problems can be easily found and fix.

Of course this van had a 2 yo rad, that is didn't tell.

It as been running now (this morning) for 55 minutes, same result as yesterday. So I'm done with this one, if the problem come back it's a head job.

Ben

Wed Dec 16, 2009 11:23 am

Quote: I'm perplex about those test, i can't inject air into the cylinder (lost of pressure on the coolant pressure test #1) but i can do the opposite, of course the leak down as more pressure than the coolant tester pump.

Well you have a much higher pressure in the cyl, that's one thing, but also from the cyl you're pushing air thru the leak (very low viscosity) , while on the cooling sys side you're trying to push water thru the leak (very high viscosity), and at a fraction of the pressure as well.

That's why combustion seal leaks so often don't show up with a simple coolant pressure test, but doing the CO sniff in the pressure tank while running is such a relaible way to prove such leaks. Not having a CO sniffer, though, I actually like the test you did, pressurising the cyl with the coolant tester still hooked up. I'll use that someday.

Hope you were making money doing something else during that hour the thing was being tested!

Wed Dec 16, 2009 4:41 pm

Great work!

I would love to see a video of a system bleed.

Wed Dec 16, 2009 7:19 pm

blueridgedog wrote: Great work!

I would love to see a video of a system bleed.

This IS a coolant bleed video :-)