fuel injector o-rings .. black vs. orange

[brianl703]

I just got done replacing the fuel injector o-rings on my 1988 Mustang 5.0 because one of them was leaking and I noticed that the replacement o-rings are orange while what I can only assume are the original o-rings from 1988 are black.

Does the difference in color indicate that the replacement o-rings might be made of a different higher-quality material?

Not that it much matters, I guess--it took 16 years for the black ones to start leaking.

 

[dkcase]

I just replaced the o-rings on my 89 Crown Vic 5.0.

They are brown, Borg-Warner. The originals were greenish.

On the bottom end there is a plastic washer, then the o-ring, then a cap. One of the plastic washers is a different color than the others. ??

All those caps had to be broken to get them off, very brittle, and I drove the new ones on using a socket. That sound like what you had ?

Anyone planning this on their 5.0, I don't see how you could replace one , unless it's not old at all. I think disturbing them would cause them to leak. Plan on doing at least the 4 on one side.

 

[JohnBrowning]

The OEM's normaly color code their o-rings but this is not the norm on the aftermarket. Usualy if you vechile is more then 1-2 years old the origanal ones from the OEM have been superceded several times and will not match the production parts exactly. You will often see engineering notes telling the parts guys that blue or what ever color 0-rings now replaces all previous colors etc..... Service parts and productions parts are two different animals all together!

An o-ring for a fuel injector is going to be made from a fuel,oil and solvent resistant polymer. It should be pliable,soft, and very tough.

 

[brianl703]

I jumped the fuel pump so it'd run without the engine running and checked for leaks and there are no leaks so the new O-rings are doing their job.

I'm still waiting for the PCV hoses so I can re-install the upper intake, the stealership didn't get them in today.

 

[brianl703]

Sounds about right, except that the caps on mine were not brittle and I didn't need to remove them to get the o-rings off. I just used a pair of pliers to grab the side of the o-ring and pull it over the cap. About half of the o-rings ripped apart when I did that. The new o-rings came with a cone-shaped plastic thing that I used to install the o-rings over the cap.

For the upper o-rings, about half of them came off the injector when I removed it and I had to use some pliers to get them out of the fuel rail.

I used a q-tip and isopropyl alcohol to clean out the the place where the o-ring goes into the lower intake manifold for each injector.

Now I just need to get the upper intake reinstalled after I get the new PCV hose from the stealership...

The o-rings are used are GP Sorensen brand as sold by Autozone (who only had one pack of 8) and Advance Auto (who also only had one pack of 8). I needed two packs so I went to both places.

 

[brianl703]

I got the PCV hoses, installed them along with the intake, put everything back together and darn if this Mustang doesn't seem like it's running better than ever. Maybe it's because it had some vacuum leaks which I fixed by replacing those hoses? I also poured a little bit of Marvel Mystery Oil down each of the intake ports while I had the intake manifold off figuring that it might clean some of the deposits off of the intake valves. The Marvel Mystery Oil soaked in for at least 24 hours.

I just wonder how many trouble codes are stored in the computer since I turned the key to the ON position with the fuel injector harness disconnected...