Fuel injector ?

[JMAN718]

Hey Guys,

How difficult is it to change out fuel injectors. Does it require any special tools?
Is there any special prepping that I need to know. Any help would be appreciated.
1983 SC 3.0 engine.
Thanks Jman718

[Sigurd]

No problem. The injector is fastend with an o-ring. Just pull the injector out of the housing. Do not pull by the hose. Replace the o-ring while you are at it.

[psalt]

Jman,

The injectors are mounted in plastic sleeves that are staked into the manifold runners. The injector has a rubber o-ring to seal to the sleeve and the sleeve has the same material o-ring to seal to the hot aluminum manifold. This was a poor design choice compared to other OEMs that used CIS. The sleeve o-rings usually bake, harden and crumble, leaving a vacuum leak. Before you start, try wiggling the injectors and watching the sleeves move, and check for vacuum leaks with an unlit propane torch. Many times the injector o-rings will grip the injectors and when you attempt to pull out the injector, the entire sleeve will pull out and destroy itself over the stakes. My advice before pulling on anything, is to check for leaks at the sleeve (most at this age are leaking) and plan to replace the sleeves or at least the sleeve o- rings. The reason you should think before you act is that you need to grind down the stakes with a dremel tool before you pull on the injectors, or you may be removing the intake runners to grind them down on the bench.

Paul

[JMAN718]

Thanks Guys, for the info. I will check the injectors for vacuum leaks. Also, is there a thread on this forum that shows this process? Its better for me to see something first, before I attempt this project.
Thanks Jman718

[snbush67]

Jman,

To check for injector (sleeve) vacuum leaks you can spray starting fluid around them when the engine is running and listen for an increase in idle speed, it will be really hard to narrow down which one if any are leaking.

Before you purchase new injectors remove the old ones while still attached to the fuel lines and get six glass jars or beer bottles, put each injector into a glass jar and check the output by measuring.

There was a thread awhile back that showed how to remove the injector sleeves while the CIS is still in the car by forming a hook type tool out of thick wire (coat hanger). I would recommend against it as the old injector sleeves will be dry and brittle and likely will crumble when you try to remove them. It is best if you are going to replace the sleeves to remove the whole intake first.

The injectors will come out you just have to pull up on them really hard to get them out, it is possible some of them will come out with the sleeve attached, if you are going to do this you should purchase new O rings first so you can replace them. The old o rings will likely be brittle and you will have to break them off the injectors, the new ones simply slide back on.

To change out the sleeves you have to grind out the small staked areas with a dremal and then pull them up and out. You can see the small staked or punched ares of the edge/opening on the intake runner when you look down at where the sleeve goes in.

Hope this helps,

Shane

[JMAN718]

Thanks Shane,
I will give the starter fluid a try. I hope this will solve the under performance feeling I am getting, when I am accelerating?

Thank You, Jman718