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 (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) and this in the front (Crown Automotive 53030991 PCV Elbow for 96-01 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 (1988 JEEP WRANGLER Standard Motor Products V236 Standard Motor PCV Valves | Summit Racing) but I need something without a 90 degree in it that flows about the same as the Standard Motor Products V236. Any ideas?
Jeep YJ PCV Valve
wjdennison
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This is the path that air comes in and is sucked out of the crankcase and incorporated into the intake.
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Okay, I will get some pics tonight as well. I was going to come off the back of the carb. to the rear of the valve cover fitting as the AIR FEED (my MC2150 carb. has a nipple in the back that is behind the air cleaner, so it is a clean source of air). Then I was going to go from the front of the valve cover with the GASES PUSH to the front of the MC2150 carb. where there is a hose fitting to I assume re-burn the gasses. The FRONT would have the PCV valve. I could reverse this of course and criss-cross the hoses, but does it really matter?
What is good though is what I am hearing is I should not use the metered orifice fitting in the back, but a regular one of these Crown Automotive 53030991 Crown Automotive PCV Hoses | Summit Racing only, still need to find a PCV that will fit the grommet, PICS and MEASUREMENTS coming soon.
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Awesome, that help a lot. Does the rear one tube connect to a nipple on the intake manifold?
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Also, that right there IS my valve cover that sits on the 4.0 head.
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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From what I understand, the pcv also acts as a fire prevention to the crankcase in case of backfire. Therefore I would leave it as intended. But I would also check with someone more knowledgeable than I.
We've seen more than one post about engine fires. I make it a point to keep my engine bay oil free with regular cleaning with my 1800 psi powerwasher.
We've seen more than one post about engine fires. I make it a point to keep my engine bay oil free with regular cleaning with my 1800 psi powerwasher.
JonStevens is showing a fuel injected motor.
On a carbureted 4.2, the PCV valve is at the front of the valve cover and the air intake is at the rear. If you're running a carter carb with a stock air cleaner, there's an opening at the back of the stock air cleaner that should have a plastic nipple with a hose running from that nipple to a plastic fitting at the rear of the valve cover.
If you have other than a stock carter, perhaps someone has a pic of where and how they draw clean air into the engine with an aftermarket carb.
Good Luck, L.M.
On a carbureted 4.2, the PCV valve is at the front of the valve cover and the air intake is at the rear. If you're running a carter carb with a stock air cleaner, there's an opening at the back of the stock air cleaner that should have a plastic nipple with a hose running from that nipple to a plastic fitting at the rear of the valve cover.
If you have other than a stock carter, perhaps someone has a pic of where and how they draw clean air into the engine with an aftermarket carb.
Good Luck, L.M.
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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After all this...
For what it's worth, I have two 4.2 jeeps. One has an MC2150 carb, the other has a holley fuel injection. Nowhere in the efi instructions does it require converting to ccv rather than pcv.
I am running both on pcv configuration with no issues.
For what it's worth, I have two 4.2 jeeps. One has an MC2150 carb, the other has a holley fuel injection. Nowhere in the efi instructions does it require converting to ccv rather than pcv.
I am running both on pcv configuration with no issues.
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Okay, here are some pictures. To confirm, the holes in the valve cover are just short of 1.5" wide. The inside diameter of the grommets I got to fit in those holes is .94". LuckyMac that is what was on the Jeep when I got it BUT the rear valve cover hole had this in it 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 instead of something like this Crown Automotive 53030991 PCV Elbow for 96-01 Jeep Cherokee XJ.
I am using a Motorcraft 2150 carb. (about to be installed). You can see on the back of the carb. is a hose nipple that comes up through the carb. and behind the air filter, SO that is the nipple where I was going to attach the hose for the rear valve cover fresh air elbow. BUT... I still need some type of PCV valve for the front valve cover grommet or elbow.
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I am using a Motorcraft 2150 carb. (about to be installed). You can see on the back of the carb. is a hose nipple that comes up through the carb. and behind the air filter, SO that is the nipple where I was going to attach the hose for the rear valve cover fresh air elbow. BUT... I still need some type of PCV valve for the front valve cover grommet or elbow.
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But you are STILL running the 4.2 head right? So you can use the standard 3/4" wide PCV valve?
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I seem to have learned something, there are 2 types of PCV valves. One type uses gravity to seal a ball bearing into a seat the the bottom of the valve and the second type uses a spring to do the same as the ball bearing. The second type can be mounted horizontally. Has anyone used on of these for an application such as the one I have?
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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Correct. That was me letting you know I run pcv in both rather than convert efi to ccv
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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Yes to your statement. I think you can go whichever route gets you crankcase ventilation. Pcv or ccv, they both do the same thing.
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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I see you got a chance to post valve cover pics. What is the diameter of the two holes exposed on the valve cover? Also might want to cover those holes so nothing drops in there.
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See post with the pics, I say "To confirm, the holes in the valve cover are just short of 1.5" wide. The inside diameter of the grommets I got to fit in those holes is .94".
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Others have posted that if I am running a carb. I need to do PCV versus CCV. Is that not true?
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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I refer to post #25, I wouldn't venture to advise which is most correct. Just not my baliwick. I will say I'm running pcv on both of mine and will continue.
BUT. I personally think it doesn't make a difference as long as there is one or the other working correctly. Just my opinion.
BUT. I personally think it doesn't make a difference as long as there is one or the other working correctly. Just my opinion.
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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If you already have a grommet that fits, you might be able to use the smaller brake booster grommet as a bushing to insert pcv valve and be done.
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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Definitive solution.
Pic1 your large gasket and 4.2 standard pcv grommet for pcv valve.
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Pic 2 assembled with pcv valve inserted.
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Or not.
Pic1 your large gasket and 4.2 standard pcv grommet for pcv valve.
Or not.
'89 YJ, Golen 4.6 Sniper EFI, 2-1/2" Ex. AX-15, Atlas ll SYE, Adams shafts, F&R ARB, 3
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I did a little more research and found that...
*PCV system is better for the older engines with more wear and resulting higher crankcase fumes.
*Also safer due to there being fuel in the intake manifold on carbed vehicles and the potential for combustion on backfire.
*CCV may not relieve as much crankcase pressure due to the small size of the orifice.
Conclusion...They both perform the same function, but on our old carbuerated heaps the PCV system is the most logical way to go.
* Again just my opinion...
*PCV system is better for the older engines with more wear and resulting higher crankcase fumes.
*Also safer due to there being fuel in the intake manifold on carbed vehicles and the potential for combustion on backfire.
*CCV may not relieve as much crankcase pressure due to the small size of the orifice.
Conclusion...They both perform the same function, but on our old carbuerated heaps the PCV system is the most logical way to go.
* Again just my opinion...
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