'87 635 Fuel Injector R&R

[kaylix]

Hello everyone, looking for a little advice. I successfully removed my injectors and cleaned and tested each one. I'm trying to reinstall and I am having a really hard time getting them back in the fuel rail. Any suggestions would be welcome.

[Cactuar]

Add a light coat of oil/grease on the o rings. If they are new they will take a bit of hard pushing to get them in the rail, at least it was like this on my M30. They went easily in the intake manifold though.

[RSheiman]

A little wd 40 on each o-ring.

[DesktopDave]

+3...a little engine oil, WD40, grease, assembly lube or even a dab of silicone lube. Those o-rings are mildly oversize to ensure no leaks and will easily catch on the lip of the injector if they're not seated squarely in the bore. Some replacement o-rings I've used on other makes seemed to come in different sizes depending on the fuel rail, but that's not the case with our cars as far as I've seen. I usually give injectors a little wiggle & twist when I install them. It really helps to center that o-ring in the bore before pushing them home.

Be aware that many shops have replaced the older Nitrile/Buna-n rubber with Viton. Viton is far more alcohol resistant but less pliable, I've struggled with them a bit.

Ignore any temptations to use a rubber mallet...

[kaylix]

Thanks for the suggestions, this made it much easier!