sealing a thread

[RaceDiagnostics]

Guys, my new transmission oil cooler was supplied with a brass insert so that it could be used with two different hose types, I need the adapter in place for my car.

I will never need to remove this once in place so want to fit it permanently.

Any suggestions on what to put on the threads that will both hold it and seal against leaks as I've no confidence in the o ring, its leaking already.

 

[Pete.]

Loctite lock&seal

 

[RaceDiagnostics]

Nothing special needed for hot transmission oil?

 

[normspanners]

Nothing special needed for hot transmission oil?

yeah keep ya fingers off it !!

 

[RaceDiagnostics]

Thanks guys, OK I'll order up some loctite 243.

 

[normspanners]

That should be fine, bad that the o ring leaks !!

 

[knighty]

was it sealing against the o ring properly ?

an o ring between two flat surfaces should make a pretty good seal - I'd prefer that over locktight etc. because it will seal it before the threads instead of in them

 

[sg66]

o ring should have a recess or your just going to turn it into a flat washer, another one for loctite, i always use it on things i don't want to leak, from oil to gas

 

[rtbcomp]

^^ I had loads of trouble on my air compressor, the blanking plug in the end of the tank was sealed fitted with an O-ring between two flat surfaces, in the end I made a lead washer to seal it.

 

[Rocketman]

Just out of interest why do you think PTFE tape wouldn't have been good enough?

 

[Kayos]

Just out of interest why do you think PTFE tape wouldn't have been good enough?

Ptfe is technically a lubricant, only works on taper fittings as a sealanr

 

[Rocketman]

Ptfe is technically a lubricant, only works on taper fittings as a sealanr

OK not really true, it's used on straight thread as in both the impregnated form and in the tape form. I use a lot of water/air/oil fittings on tool designs.

 

[brightspark]

get 3 long strands of ptfe tape twist it in to a rope and wrap round your thread it acts as an o ring and u cant snap it by hand

 

[Kayos]

OK not really true, it's used on straight thread as in both the impregnated form and in the tape form. I use a lot of water/air/oil fittings on tool designs.

Shouldn't use tape on parallel threads, unless your using it as a washer, and some paste. The fact people use it doesn't mean it's correct

 

[Pete.]

get 3 long strands of ptfe tape twist it in to a rope and wrap round your thread it acts as an o ring and u cant snap it by hand

They actually make that - Loctite 55. I have a pot of it great stuff.

 

[slim_boy_fat]

Lidl have thread locker atm, I bought some because it's waaaay cheaper [£2.99 iirc] than the Loctite I have, but haven't tried it yet.

 

[RaceDiagnostics]

Well I was wrong, I had assumed that the lower bush was leaking as there was transmission fluid drops under the car when I put it back together.

I got the car up on the ramp this morning for a closer look.

All clear here, sorry for the fake news.

A couple of inches away the pipe connects into ahose which is now leaking, no easy way to repair this in its location, a new hose is £75 and about 8 hours for me to get it fitted.

 

[RaceDiagnostics]

OK after thinking about this for a few minutes I have a plan, cut the hose section out and replace with some fuel hose and jubilee clips at each end directly onto the aluminium pipework, I am pretty sure the oil pressure in the transmission should be fairly low.

The full pipe looks like this and would be a pain to fit as the exhaust needs to come off for access.