Fuel injector replacement Q

[Wyvern]

I am planning on changing my fuel injectors in my 75 2.7
My question should I just go ahead and change the sleeves as well ?

The injectors for my car really are quite inexpensive and the sleeves not that much more.
Or am I just doing more than I need?

[47silver]

My air box blew so, i had to take the cis apart.
1. replace the sleeves as the o ring will be brittle.
2. To replace the sleeves you must grind off 3 tabs (stakes) at the intake tube that hold the sleeves in place. I dont know if it can be done in the car easily. But you will have to use precautions to prevent debris from going into the intake.
3. If you do remove the cis: get the following.
new rubber isolators for the air box.
new breather gasket.
new o ring for the engine mounted thermostat.
new washers for the intake manifold nuts.
new nylock nuts for the breather (4), engine thermostat (2),
new o rings for injectors.
new o rings for the sleeves
new sleeves.
new gasket to mount fuel distributor to the air box.
new o ring for throttle body.
new rubber connectors from the air box to the intake manifolds (6)
black paint to paint the air box mounting braces.
you may want to replace the gas lines i did not at this time

i am not done as i am waiting for my used air box.
gary

[mholbrook38]

Wonder if there are any "upgrade" fuel injectors. What would be the stock number on a CSI fuel injector and what might be larger or an upgrade? Anyone out there know?

Mike

[James Brown]

all the injectors are the same for your cis, sorry, one of the limits of the cis system

[Walt Fricke]

To go with your six new injectors, I'd purchase six extra "sleeves", along with six sleeve gaskets, plus six of the larger, fatter O ring gaskets which hold the injectors into the sleeves.

Then I'd replace only those sleeves which broke or pulled out when I pulled out my old injectors. And they can pull out even without your having done any grinding.

I am not persuaded (though I don't claim the wisdom of the ages on this) that you get an air leak through the sleeves if they are otherwise intact just because they and their own seals are old. It is enough of a pain to replace these that I favor leaving well enough alone. The whole deal seems like it is loose when you wiggle things anyway, but my experiments with pouring some fluid around them with the engine running have not indicated leaks, the time or two I have tried this.

But if you break one, and decide after replacing it that it is easy, you can always do all of them. The main thing is to be ready for breakage as you pull out injectors.

As for grinding off the protrusions, you can figure out a way to shove something down into the hole to prevent debris from getting into the intake port. Put some grease on a rag to help catch them. Grind with a vacuum cleaner wand sucking away. Etc.

And you will want to fabricate a tool so you can punch three new protrusions ("stakes") into the manifold to replicate the ones you have removed, so the new sleeves stay put. Not that difficult to do.

Walt

[psalt]

Walt wrote,

I am not persuaded (though I don't claim the wisdom of the ages on this) that you get an air leak through the sleeves if they are otherwise intact just because they and their own seals are old. It is enough of a pain to replace these that I favor leaving well enough alone. The whole deal seems like it is loose when you wiggle things anyway, but my experiments with pouring some fluid around them with the engine running have not indicated leaks, the time or two I have tried this.

Hello Walt,

My experience is that the outer sleeve O ring leaks more often than the insulated injector seals. They are both the same material, but the outer sleeve O rings are usually (not always) baked to a crisp. I much prefer the VW/Audi threaded solution to this design. The manifold must be sealed from air leaks, and testing with a liquid will not give you the correct result (too thick). Testing with propane gives a much better indication of an actual vacuum leak. Six marginal injector sleeve O rings are more than enough to throw off the air sensor plate height during cold running. I start with the assumption that they are all bad after +25 years, grind all the stakes before starting with a Dremel, vacuum and blow the grit away, then start the job. No surprises or debris worrys when a sleeve pulls out. I use a round flat punch for the stakes, not the factory square stakes, but they stay on place. Everytime I have done this job, cold starting, cold running and idle performance is better.

Nice valve grinder, can I come over and grind some old Jaguar valves ?

Paul

[47silver]

Some say to use vasoline on the o-rings, but is this ok for rubber? Would glycerine or even gammi fluge be better?

[psalt]

The O rings in the engine are not rubber and can be lubed with engine oil.

[47silver]

engine oil is great thanks

[Wyvern]

Thanks to all for the info
I will be ordering the sleeves as well.

Not sure if I will plan on replacing all or do the "check it out" method.

If I take the CIS off and remove the intake tubes I may machine a groove for a circlip ... that really is what should have been done in the first place.

[Walt Fricke]

Paul

Any time. Best after I get the coolant fluid system working.

You live in Colorado?

Walt

[psalt]

Walt,

No, about 1800 miles to the right. I'm just jealous.

Paul

[roadster49]

I am replacing the sleeves and o-ring seal on an 83SC. Do I need to use Loctite 620 per Bentley manual on the o-ring and top of sleeve? The sleeves I have pulled are coated with some type of sealer, How important is it to restake the sleeves? So far three came out without grinding, 2 are only slightly staked and one looks like someone went nuts with a cold chisel.

If a sealer is required Was wondering if Curil T would work instead of loctite 620?

[ManniB]

Originally Posted by roadster49

I am replacing the sleeves and o-ring seal on an 83SC. Do I need to use Loctite 620 per Bentley manual on the o-ring and top of sleeve? The sleeves I have pulled are coated with some type of sealer, How important is it to restake the sleeves? So far three came out without grinding, 2 are only slightly staked and one looks like someone went nuts with a cold chisel.

If a sealer is required Was wondering if Curil T would work instead of loctite 620?

On my '81 SC engine, I have not used any sealer and I have never heard of anyone using it. The sleeves are sealed by the o-rings and are fixed by staking the alu around them (did that at three points). Otherwise, they might be poped out by the next missfire.

- Manfred

[fanaudical]

I used Curil T on the outside top rim of my sleeves when I reinstalled them. (I figured it couldn't hurt.)

[Walt Fricke]

Staking or some clever substitute certainly needed here. I have thought that just the reaction to injection (which is, of course, continuous) could pop these out all by itself. But I have never experimented to see if this was so.