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Johann · Joined: 07 Aug 2016 Posts: 176 Location: Netherlands

I have removed all my K-jetronic components to have them rebuilt and balanced by a CIS Specialist. One thing i noticed as I removed the injectors is that the holders are quite loose.

It might very well be that the car is leaking around the holders. What do you guys use to "seal" the holders?

I have been on the interwebs for hours looking for a type of thread locker or sealant. The only thing I can find that is compatibe with plastic is LOCTITE THREADLOCK TAPE 249 or similar plumbling tape

Your help is appreciated.

924RACR · Posted: Sat Aug 26, 2017 11:40 pm Post subject:

I have this for numerous other threaded fittings, so used it as well - combination thread lock and sealant:

(Permatex 54540)
https://www.amazon.com/Permatex-54540-Pneumatic-Hydraulic-Sealant/dp/B000HBGL14/ref=sr_1_fkmr0_1?ie=UTF8&qid=1503751105&sr=8-1-fkmr0&keywords=Loctite+54540

Not sure if it's available in your area, maybe there's something equivalent?
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Vaughan Scott
Webmeister
'79 924 #77 ITB racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

MikeJinCO · Posted: Sun Aug 27, 2017 11:33 pm Post subject:

I can't say that this is the best solution, but for sealing threads with plastic pipe a teflon pipe dope in a tube(plumbing supply) is normally used rather than tape as it flows better and won't break the plastic as tape possibly can. Tape is best on metal to metal threads.
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Mike
Poco a Poco, '80 future track car
'77 924
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Johann · Joined: 07 Aug 2016 Posts: 176 Location: Netherlands

Thank you gentlemen, I have ordered a tube of Loctite 570. It seems to be the closest to the Permatex and comes up when searching for pipe dope too

924RACR · Posted: Mon Aug 28, 2017 10:47 pm Post subject:

Actually, turns out the teflon tape isn't so good for motor applications... it doesn't seal pipe thread, but reduces the friction to allow you to tighten the thread more to achieve the metal-to-metal seal... hence why I was pointed to the Permatex stuff instead...

Very important on my racecar, where vibrations will loosen EVERYTHING not locked down...
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Vaughan Scott
Webmeister
'79 924 #77 ITB racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

924RACR · Posted: Mon Aug 28, 2017 10:50 pm Post subject:

Looked a bit more... I wonder if Loctite 545 might be a closer match to the Permatex...
_________________
Vaughan Scott
Webmeister
'79 924 #77 ITB racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Carrera RSR · Joined: 08 Jan 2010 Posts: 1581 Location: Somerset, UK

I used Loctite 577
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knobby · Joined: 23 May 2011 Posts: 37 Location: Cincinnati,Ohio

I have a loose one.The holder(socket) seems loose on mine.
I just bought a set of new injectors and am getting ready to install them and rectify the loose thread.I don’t know yet if the looseness is because of backing out of the head or what but I was wondering how your injector install went and what thread sealer compound you ended up using and also the seal between the injector and the socket/holder p/n 900 123 033 20 sealing ring,is this a generic part or did you need to obtain from Porsche?
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81 RED 931 S2(daily driver),81 WHITE 931 S2(not currently drivable).
Cincinnati,Ohio