airbox gasket failure.

[theiceman]

I rebuilt my entire engine and didn't even look at the CIS as I just did that about 5 years ago and it was running great .

I went to put the finishing touches on it and noticed that my airbox gasket had squeezed out of position. it was a while ago so don't even know where I sourced it . it is made of very thin foam almost.
I was very surprised by this . As well as all the screws on the components being loose. ( the ones on the springs. ) strangely enough I had no performance issues at all.

Has anyone else seen this and can perhaps suggest what I did wrong on my rebuild of the CIS ? maybe I tightened th e screws too much and the gasket squeezed out ?

The project now stops while I wait for a replacement gasket.

[Cdnone1]

The gasket should not squeeze out, that being said you do not need to over tighten those screws. The springs on the screws where designed by the factory to be the "original "pop off" valve in case of backfire and will not work if tightened all the way

[theiceman]

that is interesting because that's what I thought and each scre I checked was merely snug with basically the pressure of the spring holding things in place , yet it did as you can see squeeze out. I will lift off my metering components tonight and see if I can get a better pic.

[timmy2]

Wrong side of the metering plate to be any type of a pop off device unless a huge rush of air comes in through the air filter....
The gasket is just there to stop unfiltered air.

[john walker's workshop]

There won't be any running issue because it's below the sensor plate, just like the air filter. A tiny bit of unfiltered air worst case, but it doesn't look completely out.

[Steve F]

Doing this on my bench right now......run screws down just till touching, not tight, then one revolution back for all. The gasket is only $8 from our host too

[theiceman]

update all

As John points out it is below the plate so certainly explains why my car ran so well. it was in fact completely out in spots. not sure what caused it but I have a new one on order.

looks like I might have twisted it installing it.

[gazzerr]

When I installed it I stuck it to the airbox. I was actually wondering if I should have stuck it to the bottom of the metering unit instead?

[theiceman]

gazzerr my thoughts exactly.. I stuck it to the airbox last time .. gonna try the metering unit this time.

[theiceman]

All. I noticed while cleaning up,there is a drain hole in the airbox directly below the metering plate.
its function is obvious but i was wondering if i should have a tube on it. currently it would drain anything right on to tbe top of the engine.
thanks

[Flat6pac]

The drain was used pre 78 because the oil tank vented into the side hole in the airbox and oil fumes would stick and flow to the low spot. With the 78 and later the oil tank became vacuumed into the throttle body for burning. That's why the later cars stumble with the oil cap removed.

Bruce

[meichten]

Recently replaced my gasket as well, I stuck mine onto the mcu as that's where the adhesive appeared to be before. I let it sit for a while before I placed it back on the airbox. As mentioned above I put the mcu back on hand tight, then backed off a full turn. No issues to date.
I found another thread on here before which confirmed no hose required from that drain hole in the airbox, however you can put one on and it should connect to the overflow container in front of cylinder 6. Purpose is for any fluid that would ever get into the airbox.

[theiceman]

thanks guys just waiting for part to.show

[gazzerr]

The drain hole on my '82's airbox has a rubber stopper in it.