Thermostat Changing

Can you heat the knife up, so that it melts the silicone a little, maybe get it very hot..

Silicone doesn't really melt - it'll degrade rapidly when you get over

Twisting the thermostat off, or pulling it might be an option. Silicone is not very strong.

Give it a good wrench lad.

Either this stuff is strong, or Im not very strong. I'd wager the latter.

Any tips yet on what stuff to use? So far, I have three different compounds, between Loctite Superflex Black (5940), Hermetite Instant Gasket, a specially formulated orange RTV Silicone Rubber, or Hermetite Red, original semi-hardening gasket compound.

I think I should steer clear of the third compound?

Ta Simon

Haven't come across the Loctite one, but any of the others would do the job. Thermostat housings don't need any high tech sealer.

AFAIK all silicone sealants are much of a muchness. Was told by a Dow Corning rep once, that the silicone sealant they made for sealing sinks, baths etc, was the same as they sold for engineering uses, apart from it's colour. Prise it apart with a knife. Mike.

Nope. They don't do them. Nissan Dealer said I have to use silicone, but done use any of that red or blue stuff he said then pushed a tube in my face for £10... should of got that. Now I have three tubes of sealant costing £4 each.

Cheers Simon

Oh well. Fingers crossed then. I'll get me knife out.

Might be taxi time tomorrow. hehehe.

Cya Simon

Screwfix among others do a sealant remover

Can't you get a gasket for the new one?

What utter bollocks. Just buy some gasket paper and cut your own.

Well, that's how it's done factory fitted. I can't imagine Nissan with their extornionate prices not wanting to use a paper sealant...

I'd be surprised if it was. Not calling you a liar but it'd cost more and car manufacturing is all about saving every penny.

The message from Conor contains these words:

Renault told me the same when I asked for a gasket for the Clio's thermostat. Just said "Oh, there isn't a gasket, just a thein smear of silicone" Indeed, when I took it apart there was no gasket - and it was the first time it'd been taken apart, too.

nope he's right, a lot of thermostat housings now a days dont use a gasket paper or o-rings, the bas is flat enough to put a smear of sealant on it tighten it down & the jobs a good un.

simon your worrying too much mate, im not sure of your mechanical skills, but when you posted earlier in the week about the same problem, then i said all you needed was a bog standard tube of instant gasket, nothing fancy, clean both mating surfaces off and refit & refill, no need to wait for it to set as you will waiting for ever. ive had them in through the workshop, remove, clean surfaces, smear of sealant & refit and road-test & all in under half an hour, less on some other models, it really isnt a problem job.

My mechanical ability is OK. Ish. Don't expect me to change an exhaust, or tinker with camshafts and such... mainly DIY+

But it's the extras you can get that's the problem. I mean, instant gasket... ok, there's several different times of that, like Hermetite Red, RTV, Black Silicone... Gawd knows what I want to get. I though the Black Silicone was the one... then a bit of Googling, I saw something called RTV... so got a tube of that.

It is all refitted and sealed up now. Well I hope it's all sealed. There looked like a tiny amount of water seeping out. Fingers crossed it's just from the rain or when I bled the engine from the bleed screw :-)

As I said in an earlier post. I think you'll find whatever the manufacturer calls it, silicone sealants are virtually all the same. RTV is only another name for it. So, if you want to save a pound or two, buy your silicone sealant at your local DIY store. :-) Silicone is better for sealing more irregular components, but for surfaces that mate quite closely, like thermostat housing, Hermatite or similar sealants are OK to use. Mike.

It depends. At high temperatures, the differences are clear. (high being >150C or so). The extra impurities in the cheap stuff cause it to degrade fairly rapidly, losing elasticity and strength.

Guy King ( snipped-for-privacy@zetnet.co.uk) gurgled happily, sounding much like they were saying :

Gaffer tape.