Hi,

 

Is it recommended to replace the plastic thermostat cover when changing out the thermostat.

 

Our vRS is taking a while to get up to temp. So I suspect the thermostat is on the way out. I changed the temp sensor the other day as this was faulty (no temp read out, high idle, and a CEL with the temp sender error code) the replacement sensor has cured all of these issue but the engine is slow to get up to temp when viewed on the temp gauge. 
 

So I was going to replace the thermostat. 
however the cover is a special order part here in NZ with a 3-4 week lead time.. 

 

So I’m wondering if it essential to replace or not..

 

Thanks

 

John S

 

Change out the stat and then you'll know if you're going to need one or not, removing it won't damage it if it's not leaking now.

7 hours ago, Johnsnz said:

So I’m wondering if it essential to replace or not..

 

There are some plastic lugs within the housing that tend to break off when it's removed. I think the idea is that the thermostat locks into (with a quarter-turn type thing) the housing with these lugs, to make it easier to install/remove.  The trouble is, after the stat has been in the engine for a decade or more, it's stuck there more than the lugs can handle, so they break off as you try to pull the housing off.

 

It's still possible to install without these, it's just a bit awkward juggling thermostat and o-ring into position and getting screws into the housing to hold it there. "Is that o-ring still in the right place" you'll find yourself worrying, until it doesn't leak and all is well...

 

 

As above. When i changed mine 1 of the 2 lugs broke off.

I could have used the old housing but had already bought a new one so fitted that.

I also used a new o ring.

I use old one when i replace new thermos and O-ring. If you get old one whit out any damage i didnt see any reason to change new thermo cover.

1 minute ago, FinnVrs said:

I use old one when i replace new thermos and O-ring. If you get old one whit out any damage i didnt see any reason to change new thermo cover.

Ouh if you have time to wait and  be sure everything goes well then order new thermo cover. But i dot see any other reason why not to use old one.

So Job done along with a fuel filter.

temp now sits happily midway on the gauge and the car warms up nicely.

 

My housing had one broken retainer tab but apart from that a straightforward job.

 

Next up is probably cleaning the EGR valve...