I have a 86 Vette with fuel pouring out of the back of the fuel rail where the cold start line goes in. What I am wondering is what's the proper size 0-Ring that needs to go in there to replace the old worn out one, just trying to get away from going to the dealer because they are charging $36 for the single O-Ring. Also whats the proper way to tighten the two nuts that are there should I be backing off the backup that is attached to the fuel rail and then tightening the other nut to it or simply just tightening the one on the cold start right to the fuel rail assembly.

Thanks

 

I did away with that silly cold start injector back when I had an 86, also did it to one of my 88's. Never had problems starting the car either.

 

What did you use to plug up the holes on either end? Did you have to use any teflon tape on the cap or plug that you used? And when you did this did your car start throwing any codes?

 

The 1st time I made my own plug. The second time I used the plug that came with the Accel big runners. If you look around I'm sure you'll find that someone sells them.

No codes will be set.

 

There were several cold start "kits" that were available for the 85-88 Cold Start Valve assembly. Some included a lot of other parts in addition to the o-rings.

There are 2 o-rings where the cold start line goes into the back of the fuel rail. One large (#107) and one small (#104) in the dealer parts diagrams. The large o-ring #107 is only available with a fitting kit, which is probably why the dealer is quoting you $36. The small o-ring is available as part of the o-ring SEAL KIT ... GM part # 17111954. This kit has 3 o-rings. One for each side of the Cold Start Injector and the small #104 for the line fitting at the back of the rail. This kit should be inexpensive. I would bet that this is the o-ring giving you problems since it is the one with the most pressure on it.

The cold start fuel line goes through a compression nut and fitting holding the #104 o-ring into another larger fitting which screws into the back of the fuel rail. When I replaced all of my injectors, in order to get the #107 o-ring by itself I pulled my cold start fuel line off and took the large fitting that screws into the fuel rail to the dealer and we found a fuel line o-ring from their stock that fit perfectly. Cost me $2.

You screw the large fitting into the fuel rail with the #107 o-ring and then tighten the compression fitting over the #104 o-ring onto the larger fitting.

Try calling Superior Chevy for the O-RING KIT containing #104, or take the whole large fitting from the back of the ruel rail and get 2 replacements at the dealer.

 

You need two orings on there.

On mine one was rubber, one was a fiber looking washer.

The oring sizes are here:

http://webpages.charter.net/khasting...uelsystem.html

I don't know about the fiber or nylon washer though, maybe two orings will work.

If you think GM made custom sized orings for those 4 years, you're sorely mistaken!


Looks like weve got a few different sizes mentioned here, easy way is to just buy a coupe of every size mentioned and save an extra trip to the store.

 

Central,
Thanks for the referral to the o ring info. I copied and filed it in my personal tech info for future reference. If you are lucky, with this info, you can go to an industrial o-ring supplier and pick them up for very little $$'s.
Jim

 

could you just 'neuter' the cold start injector by removing the electric connection to it and leaving the rest in place? Mine is not leaking externally, but it probably is leaking intermittently internally. So if I do that, will it quit, or would I need to unhook and plug the fuel source as well?

 

Good question; I`d like to know this answer also.

 

Yes, you could disconnect the cold start injector, but you also have to disconnect a sensor on the front of the engine so that no codes are set. I cannot remember the exact sensor - I have to look it up or perhaps someone will chime in.

If the injector is leaking internally - as long as pressure is present it will continue to leak.