thermostat replacement

[clartsonly]

Okay bear with me some history

for 2 years my temp gauge didn't work, eventually I changed the correct sensor and it worked, but always looked very hot. I assumed the sensor was damaged from being in the wrong hole and connected to the wrong wiring, well more recently the gauge would not go over the white block eg very cold. I changed the sensor and it is showing hot again.

SO do you think that the Van is running very hot and that is why the sensors have broken? if this is the case I am about due for an coolant change, eg over 2 years since I flushed and replace the coolant. Should I use this opportunity to replace the thermostat. It really doesn't look like a simple task. Does anyone else have any hints or tips?


in other news I changed the oil only last week to 20/50, and yesterday the air filter and spark plugs and it is like a new van responsive, idling correctly, what are the chances of changing the oil filter on its own without losing all of the oil, as I forgot to get one from gsf yesterday. I changed the oil and oil filter last year 2000 miles ago, but new sparks and airfilter have made a huge difference.

[ghost123uk]

The simple answers are as follows.

Changing the thermostat is dead simple, it's only 4 screws.

Yes you should flush the cooling system and re-fill with 50/50 water and VW G12 antifreeze (though many say the Comma Xstream Red Longlife antifeeze is pretty much the same and cheaper. see = http://www.commaoil.com/Product%20Pages ... redcon.htm" onclick="window.open(this.href);return false; ) When flushing, fill with 100% water, make sure you bleed the air out (see wiki for how to), run van for a day, repeat, repeat, then put the 50/50 mix in. This is to get rid of any / all traces of any antifeeze that is incompatible with the correct stuff.

Change thermostat whilst doing this.

I consider it very unlikely that the sensors would be damaged by any excessive heat that you are getting.
I wouldn't mind betting it is not actually running hot but your sender or gauge is lying to you !

If it still runs hot, post back if you need more help.

~~~~~~~~~~~~~~~

Fitting an oil filter will hardly loose you any oil at all, (maybe 1 pint that will be in the filter) just top up after doing it. Most recommend Mann oil filters as being the best for our engines. Even the local VW dealers are perfectly OK price wise for these.

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[clartsonly]

thanks for the reply, interesting that you recommend running for a day on tap water last time I just blasted both way with a hose pipe till it came out clear. I quite like the idea of running the engine to help get the last bits out.

so I will change the oil filter at the same time, looks like next week is sorted then. just need to fork out about £15 on antifreeze now.

[ghost123uk]

. just need to fork out about £15 on antifreeze now.

Tell me about it - I am about to have to do the same after now being satisfied that my "new" motor is OK after a week keeping fingers crossed !

I just put a link in my post above to the spec for the Comma stuff

[maxstu]

Clartsonly,

Beware though. If the four screws holding top part of thermostat housing are particularly rusted then proceed with caution. If you knacker the housing a new replacement might be difficult to source. Or costly as part is supposedly obsolete.

When I did mine I naturally cleaned up all mating surfaces before reassembly. Then fitted new seal, only to find it was the encrusted rust preventing any leaks, as parts of the housing, even though it's plastic, had become paper thin with corrosion?

WD40 is your friend

[clartsonly]

wow I was logging on to simply ask the question regarding the four bolts I assume? I am cleaning them up and do not want to commit to trying to undo one unless I can be sure I can undo them all, they are bolts arent they? they appear to currently be either 10mm and rusted and rotted away to 9.5 mm or 9mm and rusted and grown to 9.5 mm?

if they are screws I will not be able to get to at least one of them, I feel that like other jobs I have completed on this van over the years, this is another one the previous owner considered then changed their mind on.

any other advice regarding this challenge?

eg
1) yes they are screws remove the housing complete first
2) no they are 9.5mm bolts dont you have that size spanner?
3) if they are rusted forget about it, it has been the same for the last 10 years most probably.

[Grun]

clartsonly wrote,

1) yes they are screws remove the housing complete first
2) no they are 9.5mm bolts dont you have that size spanner?
3) if they are rusted forget about it, it has been the same for the last 10 years most probably

From memory... Have I told you that I am an old boy and my memory is not as sharp as it was..... and another... thing........ my memory is not as sharp as it was.
No seriously, they were 10mm (Spanner size) hexagonal bolts and are threaded into steel bushes in the lower half of the assembly.... which also rust .
If 'twere me I would try to source a new (top and bottom) thermostat housing (if you can find one) before going any further.
No less a person than Simon the Brickwerks says that they virtually always need to be replaced if of any age when disturbed.
Try the States, Vanagon, Go Westy, The Bus Depot, etc. There were some there recently.
Oh oh....... http://www.gowesty.com/ec_view_details. ... parent_id=" onclick="window.open(this.href);return false; Out of stock(Lower housing) got an upper at present.
Mike

[clartsonly]

I think I will just unplug the temp gauge

[Grun]

If it ain't broke..........

[ghost123uk]

Just checking...

We are talking about the earlier metal stat housing and not the often fitted later plastic one ?

.

[clartsonly]

no the plastic ones in the post july 1985 or 1986 I cant quite remember the "later" version

[maxstu]

You'll find it difficult to get a replacement housing that's for sure. I think Billy739 a trader on here might have one.

As Grun says they are bolts threaded in to steel bushes. Once rusted the bushes turn in the plastic housing and that's it. Kaput! If you do get em out give yourself a huge pat on the back and an ice cold beer

Be very careful, though. I would remove housing and perform task in well light area on a bench.

Good luck.

[ghost123uk]

If it is the plastic one and it turns out you need to replace it, I have 2 x spare ones.

.

[maxstu]

If it is the plastic one and it turns out you need to replace it, I have 2 x spare ones.

So, it's you that got em all?? !!

[clartsonly]

thanks for the offer I will have another check on it, and make a decision regarding removal of the whole thing, maybe I can drill the old bolts out from the underside, rather than trying to undo them from the top.

could you possibly think about costs of replacing the housing, and PM me how much one would be before I commit to ruining my camper.

thanks