CIS - taken apart- checking for leaks

[davis911s]

I have my complete CIS system taken out of my car. After days of trying to fix a problem I figured I must have a big air leak somewhere.

I looked through all the hoses and do not see any cracks or holes. I checked the rubber hose to the AAV and the metal hose to the decel valve real close and could not find anything. I also looked real close at the airbox and couldn't see anything.

Can I somehow "pressurize" the hoses and see if they leak?

Also what do you guys recommend are the other best places to look for leaks now that its all out?

Thanks

Shawn

[mca]

Look at injectors - a couple of o-rings in there. With the CIS off I would replace the o-rings and sleeve.

Also the intake hoses. I'd go ahead and replace those while the CIS is off of the engine.

If the lines at the back of the CIS are hard and brittle, may as well change those too. New lines are quite soft and supple.

[SpeedracerIndy]

Now that you have it apart, it's going to be hard. I always use propane or carb cleaner and spray it on suspected leaks to see if the idle changes while the engine is running.

I'll second what mca suggested. Big potential leak sources are the intake manifold boots and the airbox could be cracked. With the exception of hte airbox itself ($$$) most of those hoses aren't too expensive, but they do add up.

[Paulporsche]

Make sure all the vac lines are routed correctly. I had an atmo line connected to the thermovalve. I also found an open vacuum port on the back side of the TB.

I hdon't think I've heard of an AAR or AAV leaking, but the decel valves can leak. Some guys even take the decel valve out of the system, rather than replace it.

Are the intake runner gaskets and rubber sleeves OK?

Is the oil cap tight?

I'm still unclear about something: how was the engine running before you got the "new" items? Was your mixture ever checked?

[Cipotifoso]

You'll want to look at your airbox very carefully. The best way to test it would be to take off all components, block off the openings into the lower compartment, submerse it in the bathtub and slightly pressurize it with air - like testing a bicycle inner tube. I have a kit that I received from another pelicanite to do this. My airbox looked absolutely perfect, but proved to leak like a sieve from the seam. I made a couple attempts at repairing it (finding the right glue/sealer is the key) before I wound up getting a replacement stainless airbox. I'd still like to fix the old airbox, but I could send the kit to you to use in the meantime. PM me if you're interested.

Dave

[Paulporsche]

3M makes a type of marine adhesive called 5200, which is what a lot of posters said they used to fix the airbox. Boating stores sell it.

[Cipotifoso]

Thanks Paul for the adhesive recommendation. I've tried JB Weld, which just flakeed off. Then, finding out the airbox is made of rotomolded polyethylene (from this forum), tried a glue/filler supposedly suited for this application: Loctite 3030. It cost about $80, since you need to purchase a special applicator gun and mix tip(s). It turned out to be a total failure as it didn't harden up. 3M 5200 will be my next attempt. This time I'll also dremel a grove along the seam beforehand.

Dave

[davis911s]

Thanks for the replies

MCA - Great idea I will order new from host

Paul what is ATMO line?
- oil cap is tight
- rubbers look good but I think I will re-order them too

Dave
- I have two airboxes, might be good to test them both anyway. I will send you a PM

Thanks

Shawn