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Discussion Starter · #1 ·
I have an 88 Wrangler with a 4.2 engine. Their is a 4.0 head on the 4.2. The engine is carbureted. I have the valve cover with this in the rear (https://www.quadratec.com/products/51302_0103.htm) and this in the front (https://www.quadratec.com/p/crown-automotive/pcv-elbow-jeep-cherokee-xj). The front one says it is a "PVC Elbow" but it is simply an elbow, not an actual PCV valve. I have been looking for an "inline" PCV valve with proper flow that I can run a hose to from the elbow then on to the carb. I have found this (https://www.summitracing.com/parts/smp-v236/make/jeep/model/wrangler/year/1988) but I need something without a 90 degree in it that flows about the same as the Standard Motor Products V236. Any ideas?
 

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I may not be understanding what your question is... The rear should be an elbow, the front one should be the PCV valve (exactly what you linked). Again, maybe I'm not understanding but it seems like you already know what you need. Here's an crappy old pic, but the best I've got handy....



EDIT** Re-reading, I think you're looking for an inline because of the front elbow.... If that's the case, pull the front elbow, get the right grommet and a PCV valve and be done. Any parts house should have the "Help" section with a variety of grommets.
 

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Discussion Starter · #3 ·
You seem to have a 4.2 head on a 4.2 motor. I have a 4.0 head on a 4.2. The 4.0 head valve cover grommet is this (Crown Automotive 2946079 Valve Cover Grommet for 94-02 Jeep Vehicles with 2.5L 4 Cylinder Engine, 94-06 with 4.0L 6 Cylinder Engine & 93-98 with 5.2L or 5.9L Engines), it has a much larger I.D. (.94") than the grommet in the picture above. So I am looking for a PCV valve that 1) has the larger diameter to fit right in the grommet OR is inline and can be hosed into with clamps 2) has the same "flow" profile as the stock 4.2 PCV or close to it.
 

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Right, you may find (with enough research or trial and error) find a PCV with a .94 OD that's why i suggested getting a different grommet to fit the hole that fits the .72 OD of the stock PCV.
 

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Discussion Starter · #5 ·
To expand this a little.

The last owner had this (Crown Automotive 53030495 Rear Crankcase Vent Elbow for 97-04 Jeep Wrangler TJ, 97-01 Cherokee XJ, 97-99 Grand Cherokee ZJ & WJ with 4.0L 6 Cylinder Engine) in the rear of the valve cover which is a CCV fitting with the metered orifice in the bottom that ONLY allows so much air to come in from the carb. Then in the front of the valve cover they had one of these (Crown Automotive 53030991 Crown Automotive PCV Hoses | Summit Racing) that was snapped off at the top and there was an inline PCV valve "standing up" hosed in and that hose went to the carburetor I assume to re-burn gasses and such.
1) WHY oh WHY would someone have a metered orifice CCV rear fitting AND a front PCV valve? Is it for the carb. vs. fuel injection?
2) Can I get away with JUST having the CCV setup and no PCV valve?
3) Is there anything special about the valve cover that makes it a CCV specific valve cover?
4) Would a CCV setup damage the 4.2 motor or MC2150 carb? Or even make them run dirtier than they should?
 

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Discussion Starter · #6 ·
BTW, I have looked for a grommet that fits the hole that allows for a 3/4 inch pcv valve, no dice to date. One of the reasons I have started this thread.
 

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My .02 worth (and that's probably what it's worth). The stock setup on my 89 4.2 with carb had an elbow at the rear of the valve cover and a hose that drew air through a very small air filter fitting inside the air cleaner housing. At the front of the valve cover is a PCV valve going to manifold vacuum.

After removing the stock air cleaner and straightening out some voodoo vacuum hoses I simply put a short length of hose and the small air filter that was inside the air cleaner housing on the elbow. You can see it just hanging out there in the pic.


They make stylish little cone shaped air filters available at most parts stores that look better than repurposing the one from the air cleaner housing. Please excuse the main harness in disarray - the picture was taken during a period of cleaning it up, removing unnecessary wires and fixing those weird aluminum crimps wrapped in duct tape from the factory.
 

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Discussion Starter · #8 ·
Right, you may find (with enough research or trial and error) find a PCV with a .94 OD that's why i suggested getting a different grommet to fit the hole that fits the .72 OD of the stock PCV.
Either a PCV valve that has a .94" diameter or a grommet that fits the 1.47" opening with a .75" I.D. for the standard PCV valve. Yes, that is what I am looking for. OR an inline spring enabled PCV valve with similar flow specifications as stock that I can hose in so it will sit horizontally. So you know of anything that meets any of these criteria?
 

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Discussion Starter · #9 ·
VICTORY!!! I went to the PepBoys and spent an hour looking through every damn grommet they have and found one that fits INSIDE the grommet that fits the valve cover and has a .75" opening for PCV valve. The only thing, what adhesive do y'all recommend to bind these two pieces of rubber together? I have no need to separate them. They are now one unit.
 

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I'd bet any of these would work, not likely to pull apart on it's own. I'd probably use the Permatex 80019, I have it and the Gasgacinch but I'd think it would bond the two grommets better. I've never used the 80062.

Permatex 80019

Gasgacinch

Permatex 80062
 

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Do they really need to be bonded together? If so, just make sure you use something that will hold up to fuel vapors and oil. That rules a lot of stuff out. I would tend to use nothing if the friction fit is good.

BTW. You came up with a cool solution. Nice work.
 

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Discussion Starter · #12 ·
Do they really need to be bonded together? If so, just make sure you use something that will hold up to fuel vapors and oil. That rules a lot of stuff out. I would tend to use nothing if the friction fit is good.

BTW. You came up with a cool solution. Nice work.
I want to bond them together because there is actually a thin rim on the outside of the inserted grommet that is hold the little on in the bigger one. That could pop loose with all the shaking and rattling of the motor and suspension. And the pvc valve will come out with the smaller grommet. So yes to adhesive.
 
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