Whoa, are injectors suppose to look like this?

[Hotwatermusic]

So having nothing further I can do on a clutch repair job until some parts arrive, I decided to tackle another job that I wanted to do while the engine was out: the fuel injectors. I started with pulling cylinder #1's injector. It was pretty loose and came out quite easily. And my gosh is it filthy!! Is this a normal amount of crud on an injector?



Bunch of build-up inside the port as well.



And this big crack, is this red covering just that, a covering? Is that crack affecting anything?


Is there a comprehensive fuel injector clean/rebuild/repair thread? I keep reading about a "sleeve" in the searches I've done, but most threads are vague and speak as if you already know 99.9% of what's being talked about. I don't. I have no idea about these things other than what's in these pictures ain't pretty.

[schumicat]

the crack is just the plastic fan shroud and it shouldn't affect anything.

[Joe Bob]

Clean them up and test flow.....

[Gogar]

That's pretty ugly, but doesn't 'necessarily' mean they are bad. You can get 6 baby bottles and put each injector in and look at the flow pattern as you lift the sensor plate, with the fuel pump relay(if you have one) bypassed and the pump running. You should get an nice even fan of spray. Anything less and you need to clean or replace them.

Many P-car mechanics have a little hand-pump system where you can hook up each injector and hand-pump fuel (or techron) through them to clean them.

[Hotwatermusic]

I have 12 new rubber O rings for the injectors: 6 wide skinny ones, 6 smaller fat ones. I bought them on the assumption all would need to be replaced. But I can't really tell where any of them go. There appears to be an O ring at the top of the injector I pulled out. Which one goes there, the small fat one or the wide skinny one? I can't find a diagram in the Bentley manual.

[Gogar]

You have pulled the 'complete' Injector/sleeve combo.

The orange-ish "sleeve" comes away from the metal injector with some effort.

The small o-ring goes around the metal injector and seals it to the 'sleeve',
(as you may see when you get them apart),

The larger o-ring goes around the 'sleeve' and seals it to the head.

This pic shows the injector only, the o-ring goes around the narrowest part of the injector.



Here's the "Sleeve", o-ring goes up near the widest part, you'll see on that one you already pulled.

[HarryD]

Originally Posted by Hotwatermusic

I have 12 new rubber O rings for the injectors: 6 wide skinny ones, 6 smaller fat ones. I bought them on the assumption all would need to be replaced. But I can't really tell where any of them go. There appears to be an O ring at the top of the injector I pulled out. Which one goes there, the small fat one or the wide skinny one? I can't find a diagram in the Bentley manual.

This is where the PET really shines. For your 1983 car, you can see the PET here: http://www.porsche.com/all/media/pdf/originalparts/usa/911_USA_78_83_KATALOG.PDF.

If you look at page 58 of the pdf file, you will see where parts 29 and 30 go into the air induction lines for your heads. Part 30 is an O-ring and I suspect it is the larger one.

On page 67 of the pdf file, you will see parts 21 and 22 which is the injector and it's O-ring. I suspect that is the smaller O-ring you have in your kit.

You can find the PET for other years/models here: Porsche Classic Original Parts Catalogue - Classic Genuine Parts & Literature - Porsche Classic - Dr. Ing. h.c. F. Porsche AG

[RWebb]

where is the best place to send the injectors for cleaning?

[Hotwatermusic]

Originally Posted by RWebb

where is the best place to send the injectors for cleaning?

And how do I separate them from the fuel lines? The nut right at the top where it meets the injector, just take a brake line wrench to it? Are there tricks or tips I should know about?

[dhagood]

i don't know about the "best" place for injector refurbishment, but you might try witchhunter performance.

i have not (yet) used their services.

[gamin]

I have used witchhunter more than once. Their service is OUTSTANDING. Fast and affordable. Just get the gas out of the injectors, seal them in zip bag, and mail in USPS $5 box. Follow instructions on witchhunter web site. I,m in NC and I always got injectors back within a week.

[Kidasters]

Witchhunter won't service those - they don't do CIS injectors.

They do great work though - I sent them 6 injectors from my 84. They will do a chart of them all before. Then - they are cleaned and rebuilt, and then they give you the "after" chart - so you can see the improvement.

I highly recommend them.

For CIS injectors - you could try the following:

Marren - Marren Fuel Injection - We Service All Your Fuel Injection Needs

Fuel injector corporation - Fuel Injection Corporation

RC engineering - RC Fuel Injection

It's all in this thread: Fuel Injector rebuild service

[IROC]

I'm not sure how much testing costs, but you can buy brand new injectors for about $40 each. That's the route I took.

[Kidasters]

Back to the EFI injectors - cleaning is cheaper.

Through witchhunter - it is $20 per injector, and they come back brand new.

A re-built EFI injector through PP is 42 + 15 core charge.

a brand new injector (EFI) is $418!

http://www.pelicanparts.com/catalog/shopcart/911M/POR_911M_FULmot_pg4.htm#item15

[Laneco]

We have our CIS injectors cleaned at a local fuel injection shop that also does diesel injectors. For the EFI injectors, Witchunter provides astounding service.

angela

[Neel]

I've had excellent service from RC Engineering.. They give you a before and after flow specs, which was a real eye opener for me, the injectors come back flow matched and looking the same as new..

[Hotwatermusic]

Originally Posted by IROC

I'm not sure how much testing costs, but you can buy brand new injectors for about $40 each. That's the route I took.

Where can I get new CIS fuel injectors for $40? What I took to be the proper replacements here on Pelican were $120+ each. Was I looking at the wrong part?

[Scott R]

Porsche 911 & Turbo CIS Fuel Injection - Page 5

$45 for the non-turbo.

[afterburn 549]

Like all ready said - hook them up put them in a container so as to observe them....Just cause they are dirty on the outside give no credence to the fact of dirty / plugged on the inside

[jpnovak]

the bigger issue is why is there so much oily residue in your intake? valve guides? oil overfill?

I think I would pull the intake and look at the rest of the heads while cleaning out ALL of it.

Since the engine is out of the car, pull the fuel head and clean it out along with the CIS plunger. Guaranteed that its gummed with old fuel and needs to be cleaned. your throttle response will be much improved after cleaning. Generally, hesitation is gone as well.

So much "while you are in there" stuff that does not cost money.

I have had very good luck cleaning CIS and MFI injectors using some Berrymans ChemTool in a HF ultrasonic bath. Best $39 tool in the garage for cleaning up engine parts.