Head gasket??

[vault]

Still have not figure out the other issues (PMD) but now I'm loosing coolant. it is commiing out the over flow tank. Yesterday I got home and about a min after shutting the truck off the thing belched out a lot of coolant. Also when I'm driving the temp fluctuates between 185-210 with out changes in driving conditions. It will creep up to 210 then all of a sudden rapidly drop to 185. I'm thinking either a bad cap or I've got exaughst gases pressurizing the coolant system.

[JohnC]

... It will creep up to 210 then all of a sudden rapidly drop to 185...

You have air in the thermostat housing. Try bleeding it out, but, if it keeps coming back...

[vault]

how do you bleed it out?

[vault]

If it is a head gasket is there any issues with resurfacing the head? I know VW are very sensitive to the change in compression ratio caused by even resurfaceing.

[DaveBr]

On my 98 there is a small brass bleeder valve. Just open it untill air bleeds off and coolant appears.

[suburbanK-2500HD]

With the cap off the coolant container, does it bubble ?

Mine did when i got a bad headgasket, and the pressure i the system was "high"

[jerry598]

If it is a head gasket is there any issues with resurfacing the head? I know VW are very sensitive to the change in compression ratio caused by even resurfaceing.

When engine is cold, start her up and if the hoses get hard in the first couple minutes then you can bet it's the head gaskent. Don't resurface unless you have too. Just have them checked for straightness to make sure they are not warped. They might just be fine. Can't remember right now what the limits are on resurface of heads or block deck. Look at the cracks in the precups and make sure they don't cross the fire ring.

[Bobbie Martin]

When engine is cold, start her up and if the hoses get hard in the first couple minutes then you can bet it's the head gaskent.

If you are lucky, its a head gasket. Mine was a crack in #8 cylinder.

[vault]

I bled the air out (thank you) and have driven 120mi with out any noticable coolant loss and the temp gauge is reading normal. I will check the hoses. Still wondering how the air got in there in the first place. My wife's explorer just blew a head gasket two weeks ago I don't need a second.

[DaddyB3089]

Bobbie Martin Quote:
Originally Posted by jerry598 http://www.thedieselpageforums.com/tdpforum/images/buttons/viewpost.gif (http://www.thedieselpageforums.com/tdpforum/showthread.php?p=271297#post271297)
When engine is cold, start her up and if the hoses get hard in the first couple minutes then you can bet it's the head gaskent.

If you are lucky, its a head gasket. Mine was a crack in #8 cylinder. 07-15-2010 01:39 AM

Were you able to do anything to fix the crack or was the block toast? I think I have the same problem on my 1995 6.5 in dually.

[Bobbie Martin]

Were you able to do anything to fix the crack or was the block toast? I think I have the same problem on my 1995 6.5 in dually.

No, it would have needed a sleeve. Diesel Depot told me they tried sleeving a few blocks like mine, but had problems long term. I went with a new (to me) AMG block.