Thermostat Out

The easiest way to clean silicone is a not-quite-sharp knife, to get it roughly off, then a razor blade to get the last off. However, you just nered to get 'most' of it off, so it doesn't disturb the next seal. Silicone sealant seals to set silicone sealant just fine.

Oh God. Sounds distinctly like a bodge job. Could be this that's causing all the problems. I bet there's supposed to be a rubber O ring that fits around the edge of the thermostat. Sadly, they no longer come supplied with a new one and you have to either buy them seperately or use the old one. Whacking loads of silicon sealant around it is the defacto bodge and it usually doesn't work.

Easiest way is with a panscrub or some mid grade sandpaper.

I tried a razor blade, ok, not quite a razor blade, but similar... then a paper towel, followed by a quick going over with a fine wire brush used to cleaning shoes with. Works quite well. Cacked on the sealant, but Im not the best person for doing that. My hands shake too much. Im a little concerned by that, but its not your problem.

Refitted, now,bit reluctant to tighten fully up, the stuff is still wet! It's already been 20 minutes. When does this stuff go off?

Cheers Simon

Tomorrow sometime.

It's now been 50 minutes. When can I tighten up and put the coolant in?

No... sometime in the next two hours, I need to go out driving!

If not, sometime tomorrow morning, I need to go to work!

Not fair. Not fair at all. :-(

Cya Simon

Sealant should get non tacky in a few minutes, but if it's cold it's could take longer. You don't have to wait though. Just tighten it up, and wipe off any surplus. By the time you have refilled the system, the vehicle will be OK to drive. Mike.

It never does go really off. It just goes non tacky, but still feels like soft rubber.

When can I tighten up and put the coolant in?

As soon as you like. Mike.

So I don't need to wait until tomorrow morning? I understand there's two trains of thought. This one seems better.

Thank god

Simon

Thanks.

And if anyone's interested, here's photos of it all:

Ooh ick, as I was tightening up, bubbles of sealant just started oozing out. Guess it wasn't quite tacky enough? Will that be a problem? Will I have to redo this thing?

Guess fill it up int morning and check for leaks then?

Nope. It shouldn't matter, but it should have been tightened straightaway. Silicone dries initially by air contact, so large lumps will still be wet inside. All you've done in effect by tightening, is burst the outer hard skin, releasing the still soft stuff inside.

You don't have to wait. Mike.

Looks as if a std old style thermostat housing gasket would fit. Haven't seen any recently, but universal gaskets used to be available. You just pushed out the holes to suit the hole pitch of the housing. Mike.

A thin skin will form in 2 hours. If it's the stuff that smells like vinegar when it cures, you can cut the cure time to minutes by mixing in damp chalk dust or something.

You can get silicone solvents at B&Q etc.

They are fairly aggressive chemicals. If you don't positively know that it won't harm anything in what you're cleaning, then it's generally better to mechanically remove it.