Engine Oil Blow Back

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NewSixCoupe

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My '74 has Weber carbs (32/36s, I think). There are two rubber lines (connected by a PVC or nylon elbow) that run from the center of the valve cover to the underside of the rear K&N filter housing. I noticed a fine spray of oil on these lines, and discovered a good quantity of engine oil in the housing itself. It seems like excessive back pressure is forcing the oil from the engine into the housing. The lines are zip tied together, which smacks of juryrigging.

Can anyone prescribe the correct OEM fix for this situation, or is that not possible due to the Webers? I checked out realoem.com; there seems to be an OEM line shown (50 or 60 mm depending on year), but I suspect that it would be of one diameter, whereas the line in my car has two different diameters, requiring the use of the elbow as a reducer...

Finally, where can I source an adaptor kit to reinstall my factory air cleaner housing to the Webers? Thanks!

By the way, how do I attach an image?[/img]
 
Hey Len,

If you get the original air cleaner base, I also have the 32/36 Webers, and can give you some better photos of the attaching brackets.

Also, I have attached a random photo of the stock air cleaner base that I had for something else; the crankcase vent (top of the valve cover) should duct to the front carburetor from the rubber line that you are referring to. The rubber line attaches underneath the base to the bent tube at the head of my ratchet in the image:

CS_Aircleaner_1.jpg


Some blow-by is normal, especially if you have some miles and don't drive the car very much, as you may not be burning the condensation out of the motor. Excessive blow-by means rings are letting compression go by and enter your crankcase-- The top of the valve cover is letting the pressure out, with the idea that the fumes will be re-injested and burned.

You could also do a compression or (even better) a leakdown test to see if you have any ring issues. I bought a compression tester at Sears, and it's easy to do yourself.

In order to attach an image, I think you have to first post your image(s) to a web server, like a Photobucket or any personal web-space you may have. Then, enclose the url of your image with the "img" "/img" tags that are included on the post screen.

HTH...
 
Len,

There is an kit which accomodates the original airfilter hosuing for the weber carbs. I'm not quite sure who sells them, but they are available.

The weber carbs seat a little higher than the Zeniths.
 
Thanks for the help, guys. I looked at the the JAM Engineering site quickly and it seems there is one option for a Weber/Zenith adaptor. Does K&N supply filters for the stock air cleaner? I'll have to check...
 
filters for stock air box

K & N doubtful source for stock airbox filters--Purolator has them--two required--same size were used by a few other makes as I recall--check at almost any auto parts store
 
Len,

K&N makes the round type stock air filters that fit the CS. I have a pair which you can have. I used them for about 2000 miles and went back to stock air filters.

Mike
 
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