Blow by question

I've spent the last 20 mins going through old posts, but couldn't find the answer to my blowby related question. There is a good deal of oil on my air filter when I change it every 3k miles along with my oil change. I can see oil in the tube that connects the air box to the throttle body and the oil is primarily at the rear of the air filter. I've already relaced all the hoses and cleaned the inside of the valve cover about a year and a half ago and it helped for a little while, but then the blowby returned. I've come up with two possible solutions. I was wondering if either of these would help and if so which one would be best?
1. Make a "puke tube" from the front valve cover breather that dumps the oil ( i know, not environmentally friendly) and would I have to worry about frequently checking my oil level?
2. Attach a small air filter ( K&N style but smaller) to the front valve cover breather and block off its inlet on the airbox.
I'm assuming the oil is entering the airbox through the front valve cover breather when coming up with these solutions, but I could just be misunderstanding blowby. Thanks for any help.

The 4.0 uses a CCCV (constant crank case ventilation) tube in place of a PCV valve. These very commonly become plugged and that in turn will increase the amount of oil in the airbox.

The cccv tube is the one that plugs into the back of the valve cover and then into the base of the t-body.

also check the grommet as they will swell and plug off the tube also.

jeep dealers keep these in stock.

While it's true that most dealers keep these parts in stock, not all of them know what they are doing with them. Go to http://www.off-road.com/jeep/cherokee/xjtech/engine/40ltr/blowby.htm and look at the parts list; I printed that and took it to the dealer a few years ago to order the parts and the counter guy asked if he could keep it to show the 'techs' in back as they had no clue what to do about the oil in the air filter...

Yucca-Man said:

While it's true that most dealers keep these parts in stock, not all of them know what they are doing with them. Go to http://www.off-road.com/jeep/cherokee/xjtech/engine/40ltr/blowby.htm and look at the parts list; I printed that and took it to the dealer a few years ago to order the parts and the counter guy asked if he could keep it to show the 'techs' in back as they had no clue what to do about the oil in the air filter...

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I replaced all these parts a little over a year ago, bandaid fix as the problem has returned. Oh, by the way 89 XJ 4.0, 182k, loses about .5qts every 2000miles.

Sounds like a ring job is in your future.

Yucca-Man said:

While it's true that most dealers keep these parts in stock, not all of them know what they are doing with them. Go to http://www.off-road.com/jeep/cherokee/xjtech/engine/40ltr/blowby.htm and look at the parts list;

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I replaced the vacumm/emission tubes last year on my '89 Laredo. It's just two parts now - not three as mentioned on the web page. Total cost about $80.00 - the guy gave me a discount if I purchased both...last time he gave me one too....

Seemed to really help my Blow-by a lot.

Read his original post, he already replaced the hoses and they clogged up again pretty quick.

Pull the CCV and shorten it about 1/8 to 1/4 inch, that will get it up out of the oil that collects in the head/valve area. To me it sounds like you have some major build up in the return passages the oil takes back to the oil pan. Might want to consider a good machine flush or two or do the flush and swap to a synthetic lube which is very high detergent, cleans better than a machine flush only takes longer...

old_man said:

Sounds like a ring job is in your future.

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Yeah, I know. I'm not really looking forward to it. How complicated is this? Seems like I'd be taking so much apart to replace the rings I might as well just do a full rebuild. I'm not losing too much oil right now, so hopefully I'll be able to put this off a little while and wait for some paychecks to come in.