Gunked up fuel injector tips!

[rtoporgo]

Hey guys,

I just finished removing the fuel rail on my '86 944 NA, and it was an absolute whammy of an affair. All the repair manuals said to simply "lift the fuel rail", but mine would not budge. Spent about an hour tugging and pulling before it finally came off.
There were no nuts that I forgot to pull, but the fuel injector heads just did not want to come loose.

What's more... the tips look really gunked up! Is this an indication of a blown head gasket or something like that? Let me know what you think!

[Jfrahm]

The head gasket is downstream from the injectors. This goop would come via the crankcase ventilation system.

Looks normal to me but I do not know the miles and the other maintenance on your car. If your car has 100K on it and the injectors have never been out (guessing not looking at those O rings) then this is fine.

[jjeffries]

Just FYI, sssquid.com does injector servicing for $15/injector, about half the rate of most shops. BMW friends speak highly of their work, quality and service. John

[v2rocket_aka944]

do future-you a favor and clean out the o-ring bores in the manifold with a rag/towel/etc, make them clean and smooth.

grease/oil the new o-rings when you reinstall.

[rtoporgo]

Originally Posted by jjeffries

Just FYI, sssquid.com does injector servicing for $15/injector, about half the rate of most shops. BMW friends speak highly of their work, quality and service. John

Thanks for the advice! I'll actually give them a shot, got about 8 injectors I can send over. Only thing is, I already ordered some Bosch fuel injector seal kits [P/N: 1287010704 Bosch] . Should I mail them these o-rings to use? Or should I just save them for another time?

[rtoporgo]

Originally Posted by v2rocket_aka944

do future-you a favor and clean out the o-ring bores in the manifold with a rag/towel/etc, make them clean and smooth.

grease/oil the new o-rings when you reinstall.

Do you recommend any kind of grease? I think I've seen people mention ATF?

[IdahoDoug]

"Future-you" Heh, I'm going to use that phrase at least 3 times this coming week just because I like it so much!

[jjeffries]

SSSquid is run by a very responsive and personable fellow named Jay, IIRC. He answered my inquiry (sent via their website) promptly.

[v2rocket_aka944]

I usually just use a very light coat of engine oil (dip finger into oil bottle, rub finger and thumb together to spread oil drop around, put o ring between finger and thumb and continue to rub oil, then install).

Maybe not the ideal chemical but it's never given me an issue or shortened an O-ring lifespan, though I tend to take my car apart more than most would (I think I've replaced the o-rings 4+times in the last 15 years but mostly just because I was already doing something more major and the o rings are cheap)

[curtisr]

According to [URL="https://www.o-ringsales.com/blogs/what-is-the-best-lubricant-for-fuel-injector-of-o-rings/"]O-Ring Sales [/URL'' If you want the installation process to go smoothly, you should use silicone lubricant during the installation.' Still, a quick internet search will generate a list as long as your arm including vaseline, STP, gear oil, dielectric grease, SuperLube and more.

I, on the other hand, have a different favourite.

[88Silver924S]

For assembly any number of o-ring lubes will work, I have used silicone in the past. However for a lube that will make disassembly easier after months and years of hot & cold cycles has anyone used Krytox? It is supposed to be more chemically stable with heat exposure. Unfortunately it's expensive.