Injector seal replacement - please help
 

I am about to replace my injector seals because they looked old and one had a tear in it.

http://forums.pelicanparts.com/uploa...1208038071.jpg

I ordered an injector seal kit and received this. I am really confused about the content. Why 3 o-rings, 1 gray hard ring and the yellow hat. I assumed that I just needed 4 o-rings, but am now completely befuddled.:(

Based on Haynes, I believe that I need to pry off the old ones carefully and replace. Am I in left field on this?
http://forums.pelicanparts.com/uploa...1208038200.jpg

When I did mine I just replaced the o-rings.

Jon

I dont know why there are 3. But you need 2. One on the bottom and one on the top.

Be very careful putting the new plastic hat back on. it pops on. Use a rubber mallet to get it on securely. DO NOT use a metal hammer or anything else metal.

I'm sure they are just spares however I have heard of people doubling up to stop leaks.

In the "Tech INFO" center button (top of page), there is an article about DIY home cleaning injectors from our resident pro. You did not mention you planned to send out the injectors to be cleaned and this is a good option.
http://www.pelicanparts.com/techarticles/944_fuel_injector_clean/944_fuel_injector_clean.htm.

Be very careful of the injector tip no matter how you plan to assemble.

John_AZ

Here is a doc on doing the seals:
http://www.rennbay.com/injectortutorial.htm

Thanks guys. While I wait for my venturi delete kit, I am going to reno the injectors.

I had the same questions when I did my injectors but I guess they throw in some extra parts (maybe because the kit is universal and fits different injectors??).

Each injector has two seals (a top and a bottom). Since you've gotten this far, you might as well replace both.

If you decide to replace the injector hat, I would recommend using your hands or rubber lined pliers (or something to cushion the new hat) - and not tapping with a rubber mallet as you could damage the nozzle tip. If you remove the old hats, you will definitely will have to install new ones as the old will be destroyed in the process.

Attached is a photo of my injectors - you will see the nozzle and this is what I mean about not tapping with a mallet - of any kind. Also, the new hats are slightly larger than the old but they snap on closer and so the same amount if injector tip is exposed. I did mine about 15k miles ago and have had no problems and I used the exact same kit as yours.

http://forums.pelicanparts.com/uploa...1208124248.jpg

Vern

Thanks Vern. Very useful advice.

Big Thanks to all for their advice
 

I dig the injector seal swap tonight using the Rennbay instructions and all of your advice. So far so good with the next test to be installation.

Found a good way to put the new hats in place. The round opening on the needle nose pliers for the "snips" is almost exactly the same diameter as the hat, such that the flange of hat catches on the outside face of the pliers and because the opening is deep enough the hat never touches anything. I also think that bevelled edges of the cutters prevents the tip from touching anything. So place the hat in the opening on the pliers and push down gently and firmly on to injector (the injector was vertical on the work table and I pressed down with both hands). With a bit of pressure it snaps into place easily.

http://forums.pelicanparts.com/uploa...1208314703.jpg
http://forums.pelicanparts.com/uploa...1208314719.jpg

The extra o ring is for the damper, you get one per kit. Now you have 3 extras. The plastic portion is the spacer. To install the cap use a 12mm-1/2 nut, place the cap in the bore and press firmly on the injector. It will be snug and when you hear the click, it is set. Helps to heat the caps up and freeze the injector for a easier time of replacing the cap. As Tidybouy said DO NOT tap on the cap to install, make certain nothing hits the pintle.

On the damper, you will see an o ring inside the portion attached to the rail.

Dal

The strange thing about the replacement spacers is that they are approximately 2x the width of the existing ones. As such, I left the original orange spacer in place. Honestly, I do not think that the hat would have fit with the new spacers.

Looks like Tidybuoy had the same issue.

Yep..Universal injector kit from Bosch. I re used the old spacers too. Just to be certain though you may consider measuring the o ring height new against the old ring for any size difference which would determine if the new spacers are needed. The new spacers are a tad thicker than the OE.

Also use a little ATF around the o rings to help lubricate to install, helps from tearing a new o ring up.

Dal

They were really, really close. Moreover, given how tight the new set up is, I doubt that the thicker spacer would have fit.

On another note, when putting the injectors back in the fuel rail, it was a lot easier than removing them (maybe that was the ATF) - I assume this is normal. However, which groove should the retainer clip go into on the injector the first one (on the narrower part of the injector that goes all the way around) or the second one (on the wider part of the injector that further away from the fuel rail and is only on two "sides" of the injector. The reason that I ask is that I want to make sure the injector is seated correctly.

They will fit with the spacers in the kit. it's suppossed to be a tight fit.

Hi everyone,
wishing to heat up this older topic :) I am about to order such seal kits from our host here (944-110-901-00-M14) but there is a note in the catalog that "the injector hats in this kit do not fit 944 injectors.
Does anybody have any idea, why this would be the case? Is this a new set now? Unfortunately I don't know the Bosch serial number of the kit because the Pelican catalog doesn't display it.
Any suggestion is appreciated. Thanks.

Unless Pelican or Bosch has changed injector kits, I replaced the pintle cap with the ones supplied over a year ago...no problems

Here is a good thread.

http://forums.rennlist.com/rennforums/924-931-944-951-968-forum/575483-re-sealing-injectors-wrong-bosch-kit-wtf.html

Porsche Doc is THE pro. Has his own web site as well.
Porsche Forum - Porsche Enthusiast Forums - Powered by vBulletin
DOC WILEN RACING | ANATOMY OF A PORSCHE

I bought the kits in bulk with the gas screen included.

http://forums.pelicanparts.com/uploa...1300658066.jpg

GL
John

Thanks John, I will check it out!

BTW, John, where did you get your kits as bulk from?
thanks.

Tomiki,

I picked up 8 sets from an ebay seller wall5150 for my spare injectors. He is a regular seller.

Fuel Injector O-rings, Pintle Caps & Seals 8 Cyl Engine - eBay (item 180641856653 end time Mar-26-11 18:59:53 PDT)

In the picture I installed the cap on the injector without the rubber seal. (I can remove it easier). Be careful on the install of the caps. Use a little syl grease or oil.
http://forums.pelicanparts.com/uploa...1300712079.jpg

http://forums.pelicanparts.com/uploa...1300712105.jpg

GL
John

Thanks, John, that looks great! Nice to have 924S owners help each other Smile Wavy
Do you know who manufacture this bulk package or how the quality is? Have you installed and also used them in the car for some time already?

I do not know the MFG. I got an instant response from the seller on other Qs.

I have used them to replace a couple of hats and seals when I was looking for a leaky injector. I plan to use them when I clean a 2nd, spare set of "low mileage" injectors I got.
The injectors, 0 280 150 158 are very expensive new. I do know there are interchanges with slightly different lbs/cc ?? ratings but I guess I am just fixed on the original.

Stan Weiss' - Electronic Fuel Injector (EFI) Flow Data Table

GL
John

"So far----so good"

John

Looks like I will be tackling this problem as well. Injector No 1 has a cracked o-ring and is leaking fuel. Luckily I haven't hard a fire yet. Failed inspection today.

Turns out not to be the o-ring. The injector tip is cracked itself. Need to replace the injector.

Was it bubbling back out of the injector hole? I had this same issue a few weeks ago. The only o ring that will cause leaks is the top one to fuel rail.

The cap was torn and the injector tip had a small crack.

The only part I have ever used is the fat o-ring, that's what makes the seal in the head. Be careful removing and installing so that the plastic cap is not damaged. A little silicone spray helps lubricate. It also helps when the injector is reinstalled in the head.

Jon