| Author |
Message |
dbear
Samba Member
Joined: August 05, 2006
Posts: 8
|
 Posted: Sat Apr 12, 2008 1:03 pm Post subject: Leaking thermostat housing |
 |
|
| After changing the thermostat in my 1990 vannagon I cannot get the housing to seal. When I opened it up I did not see a gasket except under the thermostat. It seems to need a big square gasket. Anybody have any advice? |
|
| Back to top |
|
 |
Wildthings
Samba Member
Joined: March 13, 2005
Posts: 50352
|
| Posted: Sat Apr 12, 2008 1:10 pm Post subject: |
|
|
| There is an o-ring in there that needs to be replaced. |
|
| Back to top |
|
|
dbear
Samba Member
Joined: August 05, 2006
Posts: 8
|
| Posted: Sat Apr 12, 2008 1:18 pm Post subject: |
|
|
| there seems to be a o ring under the thermostat but it is in place and it still leaks. does it go above the thermostat? |
|
| Back to top |
|
|
stevey88
Samba Member
Joined: January 16, 2008
Posts: 1317
Location: Fremont, SF Bay Area
|
| Posted: Sat Apr 12, 2008 5:06 pm Post subject: |
|
|
| dbear wrote: |
| there seems to be a o ring under the thermostat but it is in place and it still leaks. does it go above the thermostat? |
I thought it is a rubbber 'O' ring with a square section and a groove at the inside. The rim of the thermostat sit in that groove. the 'O' ring will then seal up the cover to the body of the housing when the cover is in place.
_________________
Steve
87 Westfalia full camper 4 speed |
|
| Back to top |
|
|
dbear
Samba Member
Joined: August 05, 2006
Posts: 8
|
| Posted: Sun Apr 13, 2008 9:18 pm Post subject: |
|
|
I must have put it in wrong. Thanks. I'll fix it as soon as the weather warms up.
28 degrees in arkansas on april 13. Global warming my ass. |
|
| Back to top |
|
|
Alaskaberrys 
Samba Member
Joined: June 19, 2016
Posts: 1001
Location: SE Alaska
|
| Posted: Sat Dec 15, 2018 3:00 pm Post subject: Re: Leaking thermostat housing |
|
|
Visiting our stored Westy for a few days and thought I'd uncover it and run it for a bit. All good till the temp started rising...then LOTS of steam....
Dang.
After initial panic attack that the head gasket blew or some other costly repair it looks to be leaking between the thermostat housing and its cap.
No trips planned till spring so considering just what I might need to fix and or replace. Is replacing the housing a very difficult job? I've read the upgrade to metal is recommended. We've had the coolant pipes replaced by a shop along with the radiator so everything north of engine is new so I like the idea but would want to tackle this myself when I replace the exhaust system next spring.
Thanks for any input.
Mark
_________________
'91 Westfalia, Bordeaux Red Pearl 2.1L 2wd Auto
'91 T3 Syncro Doka, Escorial Green 1.9L TD AAZ “Gremian” (to provoke, irritate, exasperate, vex...) |
|
| Back to top |
|
|
0to60in6min
Samba Member
Joined: November 27, 2006
Posts: 3417
Location: OR & CA (Oregon/California)
|
| Posted: Sat Dec 15, 2018 3:22 pm Post subject: Re: Leaking thermostat housing |
|
|
Mark,
is this for a Syncro? - a Syncro has an aluminum thermostat housing.
if for a 2wd it's a good idea to upgrade to an aluminum one. |
|
| Back to top |
|
|
Wildthings
Samba Member
Joined: March 13, 2005
Posts: 50352
|
| Posted: Sat Dec 15, 2018 7:18 pm Post subject: Re: Leaking thermostat housing |
|
|
Sure you have enough antifreeze? If your radiator and coolant over flow line are full of slush your system pressure could be through the roof.
A light coat of high temperature silicone on the gasket can improve the seal for the thermostat. Just don't use more than a thin smear. |
|
| Back to top |
|
|
Alaskaberrys
Samba Member
Joined: June 19, 2016
Posts: 1001
Location: SE Alaska
|
| Posted: Sat Dec 15, 2018 7:57 pm Post subject: Re: Leaking thermostat housing |
|
|
| 0to60in6min wrote: |
Mark,
is this for a Syncro? - a Syncro has an aluminum thermostat housing.
if for a 2wd it's a good idea to upgrade to an aluminum one. |
No, our 2WD auto. That's why was curious about the effort to upgrade. Seems like now is a good time to do it.
| Wildthings wrote: |
Sure you have enough antifreeze? If your radiator and coolant over flow line are full of slush your system pressure could be through the roof.
A light coat of high temperature silicone on the gasket can improve the seal for the thermostat. Just don't use more than a thin smear. |
Thanks for the tip. I did find the reservoir empty which is unusual so far, but expansion tank was full and light went out right away. It'd been sitting last four months so I thought I might have left it low. Sounds like I should note to flush out the overflow lines tho, they are original. Might be gunk plugging things up.
The mix is good - at least for PNW where it's at so I don't think it started to freeze. That said, is this where you'd first see a freeze/over pressure break?
_________________
'91 Westfalia, Bordeaux Red Pearl 2.1L 2wd Auto
'91 T3 Syncro Doka, Escorial Green 1.9L TD AAZ “Gremian” (to provoke, irritate, exasperate, vex...) |
|
| Back to top |
|
|
Wildthings
Samba Member
Joined: March 13, 2005
Posts: 50352
|
| Posted: Sat Dec 15, 2018 8:24 pm Post subject: Re: Leaking thermostat housing |
|
|
Any weak point can begin to leak if the system pressure gets too high. I agree that you shouldn't see freezing in the PWN with a reasonable antifreeze mixture, I had just seen your Alaska location and was thinking you might be seeing temps well below 0°F.
A failing pressure cap could cause high pressure as well.
I would tend to pull the lid off the thermostat housing and check it for flatness the best I could with a straight edge. A new gasket might be all you need, though I would tend to still use that very thin smear of silicone I mentioned above. Just did the same today on the V6 in my Toyota Truck. |
|
| Back to top |
|
|
djkeev
Samba Moderator
Joined: September 30, 2007
Posts: 32625
Location: Reading Pennsylvania
|
| Posted: Sun Dec 16, 2018 5:42 am Post subject: Re: Leaking thermostat housing |
|
|
The thermostat housing, as with many Vanagon cooling system parts, is plastic (unless you already have a syncro or a Syncro thermostat housing installed).
The housing is held on by long studs to the head.
Road deicers, leaking coolant, etc gets onto these studs and causes corrosion to build up on the stud.
This corrosion forces the plastic housing to expand where the studs pass through and cracks it.
Take it easy but by being gentle you should be able to get the housing off without breaking the studs....... hopefully.
Mine came off without breaking and when I installed the new housing I applied ECK to the studs to ward off future corrosion. I installed a plastic housing but later ordered an aluminum housing which still sits on my bench. Couldn't justify the effort involved to replace it when there wasn't a problem. You will also need Syncro senders that screw in rather than clip into the housing.
I had top cover seepage develop which I cured on a trip by removing the top cover and smearing the Oring with Hylomar one chilly morning in a parking lot in Southern Montana. It hasn't leaked since.
Dave
_________________
Stop Dead Photo Links how to post photos
Ghia
http://www.thesamba.com/vw/forum/viewtopic.php?t=392473
Vanagon
http://www.thesamba.com/vw/forum/viewtopic.php?p=6315537#6315537
Beetle
https://www.thesamba.com/vw/forum/viewtopic.php?t=482968&highlight=74+super+vert |
|
| Back to top |
|
|
Alaskaberrys
Samba Member
Joined: June 19, 2016
Posts: 1001
Location: SE Alaska
|
| Posted: Sun Dec 16, 2018 11:54 pm Post subject: Re: Leaking thermostat housing |
|
|
| djkeev wrote: |
The thermostat housing, as with many Vanagon cooling system parts, is plastic (unless you already have a syncro or a Syncro thermostat housing installed).
The housing is held on by long studs to the head.
Road deicers, leaking coolant, etc gets onto these studs and causes corrosion to build up on the stud.
This corrosion forces the plastic housing to expand where the studs pass through and cracks it.
Take it easy but by being gentle you should be able to get the housing off without breaking the studs....... hopefully.
Mine came off without breaking and when I installed the new housing I applied ECK to the studs to ward off future corrosion. I installed a plastic housing but later ordered an aluminum housing which still sits on my bench. Couldn't justify the effort involved to replace it when there wasn't a problem. You will also need Syncro senders that screw in rather than clip into the housing.
I had top cover seepage develop which I cured on a trip by removing the top cover and smearing the Oring with Hylomar one chilly morning in a parking lot in Southern Montana. It hasn't leaked since.
Dave |
Thanks for the tips and what to expect. I think it has seeped there for a bit.
I'm liking the idea of upgrading to the aluminum housing and replacing some of the older rubber hoses while I'm at it. I've got a few months to plan the project - already in cue to replace the very rusty exhaust system (I actually found paperwork from a shop recommending to replace it all - two previous owners ago in 2007! It's ready) and this seems like it would be on par with dealing with rusted/seized exhaust studs.
PM me if you'd like to recoupe the costs for that aluminum housIng now that your van flew the coup (so to speak  )
_________________
'91 Westfalia, Bordeaux Red Pearl 2.1L 2wd Auto
'91 T3 Syncro Doka, Escorial Green 1.9L TD AAZ “Gremian” (to provoke, irritate, exasperate, vex...) |
|
| Back to top |
|
|
|
