Hi, After some recommendations of testing my waxstat to fix my high idling problems on my mk2 driver, I found that the waxstat does not move that coil back completely (the smaller of the two coils under number 26 here) http://www.gowerlee.dircon.co.uk/2E2spareslist.gif When I push the little bracket (and coil) back, the engine idles lower than when it is held back by the waxstat as if the waxstat pin does not extend enough. What do you think? I'm not sure if the waxstat is performing as it should, in boiling water, the pin starts to pop out after about 10 seconds and is fully extended after about 30-40 seconds. Is this normal? New waxstat or is something else the problem?
The waxstat pin is very likely not extending enough. The end of the pin that you can't see, inside the waxstat body, is encased in a little condom of thickish rubber. The wax is contained between the outside of this condom and the inside of the brass cylinder, so that as it melts and expands the condom is squeezed and the pin extruded. Once the condom splits, the wax is no longer completely trapped, and can gradually escape at the seal where the pin comes through. The best test for this is with a completely cold waxstat (room temp), push against the end of the pin with a force of 30-40N (imagine balancing a 3Kg/7lb weight on the end of the pin, if it were sticking up vertically). The pin should be sticking out about 2mm proud of the plastic (or alloy if an early one) flange surface that butts up against the carb body when it is mounted. If it pushes in any further than this, wax loss must have occurred, and will continue to get worse, so replacement is advised.
when i looked at it last, the pin was pretty much level with the alloy, but I'm uncertain. I also noticed some green gunk which came out of the side of the alloy. Could this be the wax or is it a seal? It seems like it has been there a while.
Sounds like a visit to GSF for a new one is the way forward TBH. I'm pretty sure they'll be cheaper than VW, and you'll get the same, genuine Pierburg part. Double-check that the pin is too far in when cold, I suppose; but if the housing is alloy it's probably the original waxstat, and the things don't last forever.
Sorry, the housing is plastic. I thought you meant the circular metallic part where the pin extends out of. I'll go ahead and get a new waxstat from GSF and report back. Cheers
Oh, I see. You mean the pin was flush with the brass inner part? That's definitely a sick waxstat. The 'green gunk' you refer to is probably some paint that Pierburg put on once they've set the brass inner bit at the right distance within the outer housing.
ordered a replacement waxstat from gsf yesterday and it's now fitted. Works great! I haven't gone for a drive yet but everything seems fine with it. Cheers for the help
just bought a new waxstat (as i broke an outlet off it) its a metal one from vw. i took the pin out that sits inside the carb and the plastic guide and replaced them with the new items. the pin inside the carb sits slightly proud and i will have to push that in to get the waxstat on and screwed into place. is that correct (if it makes sense)
Makes perfect sense, and yes. I think you'll find that you can get the screws started without too hard a push, then just wind each screw in turn a coupla turns so it sits down evenly. Just make sure the far end of the extension piece is engaging correctly (there's a slot in it IIRC that something fits into), otherwise it may not go well!
