Injector seat fitment query

[gmac78]

Alright chaps,

Decided to start a fresh thread on this matter.

Finally getting round to doing these tomorrow.

I was going to use thread tape on these but getting mixed opinions. I've got some Audi OEM white sealant that's used for sump gaskets etc. Would that be suitable for this application do you think?

Also, do you refit these with inlet manifold on the engine or is it ok to do on the bench? Do they even get torqued up?

And finally, for those who have changed these in the past due to one or several leaking, how did the car feel following fitment? I know for sure one of mine leaks boost at 0.2 bar.

Cheers
Gordon

[AndyP]

Definitely don't fit them on the engine, the old ones are going to break up as you get them out and bits will fall into the engine. A famous engine tuner did this to a friends engine and it didn't end well!

[gmac78]

Sorry, I never made that clear. I'll be removing the inlet manifold to change them out, just not sure should the manifold be bolted back in situ before the seats are refitted?

[SteveH]

I used Wurth RTV sealant on the threads when fitting the inserts and they don't leak. Fit them when the manifold is off the motor. Much easier than on the motor.

[Monkeymagic]

Same here little bit of rtv and fitted them on the bench

[gmac78]

What thread is on these seats guys, may as well run a tap down them to clean them up. Cheers.

[gmac78]

Ok guys.
To update this, injector seat thread is M22 x 1.5.

Also, following removal off the old brittle seats I decided to run a tap down the threads to clean up before refitting the new ones. Unfortunately the tap picked up on number 3 cylinder and damaged 2 or 3 top threads. Bloody typical!!. Theres still a good amount of threads below the damaged ones so hopefully will still seal. The were fitted with high temp black RTV silicone and for the one with the damaged threads I added some thread tape too.

Anyone else damaged threads on these and had to use a helicoil? If so can the helicoils be made air right with sealant?

Most annoyed at this!!!!

Cheers
Gordon

[Monkeymagic]

A few of the threads on mine were less than perfect. However the new ones went in with rtv without a fight and the manifold has been back on 6 months now and they are fine..

[gmac78]

I could have fitted the new seats ok, the threads weren't even too bad. That's what I get for being OCD!!

[gmac78]

When I say damaged in my above post, I meam stripped. Or at least a portion of the the top 2 or 3 threads are stripped.

[Monkeymagic]

I get ocd but who is going to inspect the threads with the seats in place.

[gmac78]

It was more to ensure the threads were clean for installation of the new ones.