3.0 CIS question

[kmhemi]

I had to do a partial engine drop due to oil leaks and remove the CIS. I bought new intake boots, injector O rings and all the typical stuff. here is the question:
whats the best way to put the CIS back on the motor? should i put it all together on the work bench and drop it on as one unit or is it better to mount the intake runners seperate and fight to get the airbox back on??
any advice would be greatly apprecaited...and probably save some blood and tears...

[Peter Zimmermann]

With the engine at partial drop/removed I have always completely assembled the CIS on the bench, then install it on the engine. One tip is to leave the outboard clamp on each of the six connector sleeves loose, that way small adjustments are easy to make if you need a mm or two to seat the intake runners on the intake ports. Don't tighten them until the intake runners are tight on the heads, and your support brackets at cylinder #6 and your throttle console are also tight.

[Gunter]

I did it a couple times as one unit. (Right on, Peter)

Place the complete CIS on a workbench. (I use plywood on saw horses so I can walk around the unit)
Support the airbox to make the whole CIS fairly level.
Leave the filter and cover off.
Replace the boots one by one making sure that the screws on the clamps can be reached from the front.
Set the intake runners level so they can mate with the heads later without too much twisting.
I tighten the inside clamp (Airbox side) but leave the outside clamp just snug to be tightened after the runner sits square on the heads.
Before I replace the O-rings, I soak the injectors overnight in Injector Cleaner and blow them out with air.
Install injectors. Vaseline helps to pop them into the new O-rings. Connect fuel lines.
Check/replace vacuum lines if needed.
Check the wiring harness and plugs.
Place new gaskets on the heads.
Lift the complete CIS onto the engine making sure that the 2 airbox supports are in place.
Pull the harness wires into the right location.
The intake runners will have to be guided individually into the 2 bolts on the heads.
You can twist them as needed because the one boot-clamp is just snug.
Tighten the nuts for the intakes first, then tighten the outer clamp on the boot.
Tighten the 2 airbox supports.
Connect the harness.

Important: You'll need a 3/8-drive 13mm swivel-socket and a long 3/8-drive extension (10") to reach the self-locking nuts on the heads. Small hands and dexterity help to start the nuts.

Have fun.

[kmhemi]

thanks thats very helpful...i would have fought with it a while i figure..
Can I leave the injectors out and put them in after the injection is in place? I'm going to soak them in brake cleaner but I have a couple that dont look so good so I'll probably have to get a few new ones or replace them all. if its much easier I can wait and install them on the bench. the car isnt going anywhere until spring. I havent even driven it in the rain so I wouldnt even consider snow and salt.

[Ricks911s]

Putting the injectors on after the engine is installed is not as much of a pain. Certain tasks are all but impossible to do with the engine in. For example, trying to put on the CSV (cold start valve) after the rest of the CIS is installed is not fun. Trust me. Good luck and remember to check and double check the related diagrams and you might want to replace any vacuum lines. Just a friendly reminder.

[Gunter]

Easy there........Brake cleaner is too agressive. Use a good Fuel Injector Cleaner and soak for 2-3 days fully submerged.
Just make sure that ALL fuel lines are sealed/taped off so no dirt can get in.
Either way will work for installation but I prefer later because I check the flow of the injectors by placing them (Lines connected) into 6 equal-size glass jars when all else is done and finished.

Have a fire extinguisher close by.

Don't start the engine, just ignition ON, reach into the airbox and lift the Air Sensor Plate briefly to get rid of any air in the system. Expect the injectors to make a sqeeling noise.
Empty out the jars, repeat the procedure: 2-3 seconds lifting, very briefly.
If the injectors are good, you should have an equal amount of fuel in each jar.

You can also check the spray-pattern this way plus you can see if an injector is leaking when it shouldn't.

There is also a tiny screen in the nipple on the top line of the WUR that can get dirty; check it out.

[kmhemi]

thanks again for the help. I did a search a couple days ago about cleaning fuel inectors. I could have sworn the final verdict was brake cleaner. I had better double check that...
I appreciate the replies...

[T77911S]

i dont think the fuel injectors have any rubber in them. i soaked mine in one of those cans of carb/brake cleaner then sprayed them with carb cleaner then air.
i have heard that carb cleaner can kill an O2 sensor. maybe someone can confirm/deny this.

carb/brake cleaner will ruin rubber seals

[Gunter]

The CIS-injectors are mechanical with a spring-loaded mechanism, somewhat delicate.
IMHO, Brake Cleaner is a little too corrosive.
I wouldn't use it for injectors.

But, do what feels good.