When I replaced my gauges a few months back I had a problem in that the brass adaptor for cylinder 3 came out with about half of the thread from the bung. Because of where it is I can't drill and helicoil it as the swarfe would just drop straight into the engine

There is about half of the thread left in the lower part of the hole in the block, but it is not enough for the bung to make an oil tight seal even with PTFE tape and certainly not enough to consider the use of a washer of any description to make a seal. I tried some triple bond but that has blown out as soon as I have put my foot down.

My next plan is to use some chemical metal both on the bung's thread and around the outside to join the bung to the block - I'm not worried if I can remove it ever again. I would consider brazing but I don't have the tools and TBH I think the space is too tight.

Before I crack on are there any other suggestions or alternatives that I have missed other than to replace the block

Cheers

Jon

 

Have you tried an easy out, or trying to unscrew the thread that's left behind with a pick.

if its just the thread of the bung that's left you might be able to pry it up off the threads of the bore and get in with long nose pliers.

good luck.

 

The bung is fine, it's the thread in the block that has stripped. I've cleaned all if the old metal out. If I was the bung I'd have just bought a new one

 

The stuff you need is called quick steel. It is really good and I have used it in the past to seal a crack in a gearbox housing. Here is a link http://www.emotorspares.co.uk/blue-m...FRMPtAodsy4AOA

 

I've currently got this stuff in the garage which seems to be the same unless someone can explain the difference

 

I would have a go at it with that. The area you are bonding to needs to be clean, grease-free and dry.

It also needs a goodly time to go off.

Once it's gone off it can be drilled and tapped, so ought to do your job.

 

It'll be thoroughly cleaned and then I'll put the bung and block together and use the epoxy to join them. The need to get it sealed is more important than being able to remove it again

The car won't be getting driven until at least Tuesday, but probably longer, as it has no tax and I won't get that until Monday having only MOT'd it today

 

I'd put some AROUND it and over the top edges, leaving the hole/threads for the sender/bung clear.

I fitted a temperature gauge into my inlet with some similar stuff my lad got off the local steelworks. VERY expensive, I forget what it's called.

But it hasn't moved since.

Just remember your oil pressure can peak at 8bar cold, which is around 114psi

 

Stripped it all back down and found the top half of the thread is missing - when I last had it apart it was a dull winter afternoon so having some bright light was a clear advantage.

Cleaned it all out, removed an old washer that was stuck to the block which means the bung has a little more thread to grip on to. I put some metal epoxy on the top half of the thread bung and then wound it in as tight as I dared (holding the head of the ratchet and not getting full leverage from the of it). I then smoothed the epoxy that worked out and filled around the edges like so...





The sender can still be removed and changed as required should it fail or I change gauges - I just need to make sure any new sender has a 1/8 bsp thread

If this lot doesn't hold then I'll wait until I get my Christmas bonus and pick up an STI engine to drop in

 

My bet is that that will hold.

 

Mine too

 

Is it still soft? On mine I wet a fingertip and smoothed the join between adaptor and putty, and pipe and putty.

 

No, it went off in about 5-minutes with the temps today, I did smooth it as best I could but by time I'd got it on and pressed in to ensure it was sealed it was going off and I ended up almost chipping the bits off that would potentially foul the sender. When I swap the turbo and inlet and have more room I might give it a little dressing with some wet-n-dry.

 

Are you thinking of Belzona, Jeff?

Or that stuff I was gonna borrow which also I forget.

 

Belzona, yes.

Good stuff, but expensive, eh?

 

Yeah!!! Especially the compound that you have to get for high temperatures to resist expansion.