Fuel injector rebuild

1994_850_owner · Post by **1994_850_owner** » 20 Mar 2010, 11:48

Hi You all.

I have searched the archives and could not find anything on how to rebuild a fuel injector.

The rebuild kit came with a little yellow pastic seal which looks like the one on the injector after the o ring on the bottom. I have tried to twist off the bottom but it doesn't budge Is there a trick to this?

Or do you only replace the two o rings at the top and bottom and call it a day?

Thanks again for all of your help and great advice.

Don

Post by **JDS60R** » 20 Mar 2010, 12:35

The pintle cap can be popped off but is going to break. They give you a replacement as some get so brittle they crack.

Put a new o ring on each and lube with vaseline.

A word on safety
Fires can start when the oring was lubed with the wrong type of lube and it degrades the ring material or if it was not lubed at all and gets snagged/cut during installation causing a leak. The old Hylomar sealant worked great but the new racing version (only one now sold by permatex) now has a strong acetone base and will swell the oring - so don't use it. Vaseline is the safe and easy way to go. In case anyone is curious of what happens if you use too much - the vaseline will melt once up to operating temp and you will not have to worry about it. A light coating is all you need but don't worry about putting too much on. There are lots of aother expensive o ring lubes to use but vaseline is cheap and easy to find and works with no problems.

1994_850_owner · Post by **1994_850_owner** » 20 Mar 2010, 12:42

But how do you get the new one on ???

Its diameter is so much less than the stop on the bottom of the injector. It is only plastic and I don't think that it will give that much. I don't want to break the old one to get it off and not be able to get the new one on.

Thanks JD for the quick response.

Don

Post by **charlyW** » 20 Mar 2010, 16:33

1994_850_owner wrote:But how do you get the new one on ???

Its diameter is so much less than the stop on the bottom of the injector. It is only plastic and I don't think that it will give that much. I don't want to break the old one to get it off and not be able to get the new one on.

Thanks JD for the quick response.

Don

Is it the cap on the injector with the hole in it ? You a press to push it on because there is an olive that keeps the pintle cap on, you may find a tiny filter too but make sure you get the cap on cleanly if you get a shard of metal from the olive the injector will fail over time

1994_850_owner · Post by **1994_850_owner** » 20 Mar 2010, 22:45

Well, I changed over the o rings and was about to put it all back together. I was checking everything over one last time. Just for grins I felt up the rail in each whole. All I felt was metal in 4 out of 5. In one hole there was a little split o ring all the way up. I checked again and there were not any others with little rubber o rings. I looked on the ground and found 1 more. I could not find the others.

There was NOT one of these in the rebuild kits I got at NAPA.

I'm hoping that I can go to my local Volvo dealer on Monday and pick up a set of these.

There was no mention of these little o rings in any of the posts I read. Do they normally not fall out?

I hope that I can pick up a set separately from a kit at Volvo. Does anyone know of these?

Thanks alot,

Don

Post by **charlyW** » 21 Mar 2010, 04:08

Your injector should have two black O rings then an optional larger one sealing the manifold to injector, I say optional because I am being informed that here in the UK the larger ones are being discontinued. The small black ones do perish and your main volvo agent will be able to get them, here its an over night wait. The complete set cost me less than £15 here in the UK and it make a significant difference. I can only go by the UK spec kits, as thats where I'm located, but the kit should be 10 small black injector O Ring seals, 5 Blue [if still available] dust seals around an inch in diameter. Make sure you use some simple Vaseline to lubricate them nothing else.

Best and simplest way of telling if you need new O rings is to unbolt the injector rail after releasing the fuel pressure then gently lift upwards some injectors may stay stuck to the manifold if so put those back into the rail then give the rail an gentle shake if any fall out instantly or with very little pressure new O rings are required.

1994_850_owner · Post by **1994_850_owner** » 22 Mar 2010, 09:08

Well, I found four of the little tiny "spacers" they are called. But I need five. So I checked at NAPA and they did not stock them. FCP groton has them for $ 1.49. I called my local dealer and they are $ 5.00 each!!!

Oh well, I guess I bite the bullet and get them at the dealer today, along with some vaccum line which I found all cracked and split apart.

Thanks again for all of you all's help and advice. You all are AWESOME !!!

Don

Post by **ojdorson** » 16 Dec 2010, 12:51

I know this is an old thread, but do you remember where you got the rebuild kit for the injectors?

Post by **thecheat** » 16 Dec 2010, 19:49

This is the go-to guy from what I understand... http://stores.ebay.com/Mr-Injector

PS: howto on generic cleaning

http://www.rowand.net/shop/tech/DIYFuel ... eaning.htm

Post by **ojdorson** » 17 Dec 2010, 10:45

great, thanks!