CIS injector sleeve question

[Patrickprice]

Hi,
I am rebuilding a CIS system for my father in law's 3.0SC engine and in the process of replacing the injector sleeves I noticed the old ones were peened or staked in place to keep them for popping out if the car backfired. I am wondering if I should re-stake the new sleeves into the manifold runners or is the friction enough to keep them where they belong?

[allaircooled]

Yes re-stake them. I just used a cold chisel.

[Bob Kontak]

Originally Posted by allaircooled

Yes re-stake them. I just used a cold chisel.

+1

Dremel out old stake if needed. I can't remember if I used a center punch or something like what allaircooled did. I see the chisel creating a more robust dent. Given you should get 20 years out of new seals, go for it.

[porsche930dude]

some of my sleves are rather loose up and down is that bad would it cause an air leak? they would slide right out if the stake wasnt there

[allaircooled]

The o-ring that goes around the sleeve made mine hard to remove and pretty tough to put new ones in. Mine have no movement. I am not certain, but if the sleeves are loose I would suspect that it could create a vacuum leak. Best way to find out is to do a vacuum leak test with soapy water and an air source. If you search, there is a trick with using the exhaust of a vacuum cleaner to create positive pressure and using the soapy water to find any leaks.

[Bob Kontak]

Originally Posted by porsche930dude

some of my sleves are rather loose up and down is that bad would it cause an air leak? they would slide right out if the stake wasnt there

I don't like that they slide up and down easily.

The first set of seals I replaced was in '97. The fat o-rings were really hard. Can't remember how the orange sleeve ones were as I didn't really understand CIS and the importance of air sealing.

Replaced again in 2009 for grins as the trans was being rebuilt. "Old" were way more pliable than those in 97.

Why don't you buy the six outside rings/sleeves and change one out in the "floppiest" one and see if it makes a difference.

You have a turbo so you have issues both ways. Vacuum and pressure.

Pic is of powder coated chrome runners. Don't do this as the coating will stain way more easily than basic colors.

[esonefour]

When I reconditioned mine I didn't re-stake them ,new rubbers and o-rings made them so tight.
some feel a little loose .0001 but when you start it up even at a low idle they suck right down and become very rigid.
And I was worried about cracking the plastic tubes.
Dye grinded and coated shame you can't see more of them.

[christiandk]

Personally I did not re-stake them.

With the metal fuel lines and new o-rings i can´t imagine them popping up. Gave them a little drop of super glue, though.....just in case.

[Flojo]

New O-rings do the job just fine.

Here's my how-to:
Einspritzdüsen (911SC) - Elfertreff - Das 911 & Porsche Forum

[Patrickprice]

Thanks everyone! I guess I will stake them back in. If it was my car I wouldn't worry but since it belongs to my father in law one backfire and it's on the rollback and off to the shop.

[CountD]

With the amount of vibration in an air cooled engine, you'd be crazy not to stake them. Use a Dremel like Bob said to get the old ones out - the amount of material removed can be controlled this way. Put new sleeves and o-rings in and use a center punch in 6-8 places around the edge. That's what I did. A chisel is harder to use to make enough force for a nice dent - I tried, as it tends to chip off material rather than make a dent. Super glue I would not...