F-head being pressurized

[Gary McCourt]

Hi everyone! I have a problem with my 1957 CJ3B. My F134 is being pressurized when running. Several things lead me to that conclusion. First, I have oil spraying out of the oil filler cap. Secondly, oil is collecting in the bottom of the oil bath air cleaner. Thirdly, the engine is losing a litre of oil every hour it is running.

I have a PCV valve on the exhaust valve cover with a hard line running from there to the intake manifold under the carb. Beside that is a three way fitting that screws into the manifold and accepts a hose from the air cleaner and another shorter one from the tube on the side of the oil filler. Originally, the fitting in the intake manifold was a single one. It was blocked to allow the engine to run.

Last week I made a new gasket for the oil filler cap out of two thicknesses of cork. The thicker one alone did not stop oil from blowing out so I added a second thinner one. The two gaskets together seemed to seal the cap but wouldn't allow the engine to idle-- which tells me that I have somehow managed to seal off the air entering the engine.

Does anyone have an idea of how I can solve this problem?

Thanks, Gary

[SteveKfl]

My first attempt would be to take the oil filler tube off at the carb and move it to the air filter, eliminating the air filter to carb tube, plug the carb manifold port, and see if a "filtered intake air path" into the filler tube will break the "vacuum created" with all the suction lines with no "intentional intake air" as described, or as how I perceive it sounds like it is set up.  It sounds to me like it is "negative pressure created" sucking the oil out of the engine from how I read it.  Good Luck, 

[Rus Curtis]

At first I was having a hard time visualizing all the lines.  I also think something may be crossed incorrectly where the pressure may be fighting itself.  I visited the CJ3B.info page on engines to see if I could look at a typical '57 for visual reference.
http://cj3b.info/Hurricane.html

There were none but I looked at Chabot's '59 and Piet's '56.  Neither had the elbow fitting (it seems the filter thinks f-I-t-t-I-n-g is a bad word!) on the valve cover (part of the ventilation circuit).  Can I assume yours is the same?  If so, your rubber hose connected to the Oil Filler tube (about 2" below the cap at an angle ) should only run to the similar sized fitting on the Oil Bath Breather.  The hard line from the side valve cover (where the PCV valve is ) should be the only thing connected to the intake port below the carb.

I think this is what Steve is saying.

If the plumbing is all sorted out, you may also want to check each cylinder to verify what the pressure is in each.  Hopefully, your rings are good and the valves are seating properly.  I say this because even if you chose to remove all the Ventilation plumbing, you shouldn't be losing that much oil.  If you're not noticing any puddles, you can check your plugs to see if they are fouling.  Any hint of blue smoke out the tailpipe? Just 4 qts of oil, right?

While we're at it, do you have any oil droplets floating in your radiator?

BTW, really nice job on restoring!!
http://cj3b.info/Photos57.html

[athawk11]

FYI...Many bad words appear to have been pre-loaded on the new software package.  Not sure why 'fitting' would be a banned word.  Perhaps it has other meanings that I'm not aware of.   I fixed it. 

[oldtime]

Hey Gary.
The Willys F134 crankcase was ventilated by one of 3 different methods.
All 3 can function yet only 2 of them are correct for 3B's.
We can fix what you have; or get you back to original 1957 standards if that is appealing to you.

Let's approach your ventilating system first; in order to diagnose your engine problem.
Primarily we need know....
Is your upper valve cover ventilated or is it non ventilated ?

Can you upload pics ?
We sure could use pics showing your complete ventilating  system.
We may need go beyond the ventilating system if there are other related problems.

[GaryM]

Thanks for the quick response, gentlemen. First, there is no ventilation port on the valve cover. Today, a friend came over with an idea or two about my PCV set up. We ended up plugging the intake manifold near the carb and running a straight hose from the air cleaner to the side of the oil filler tube. We also dismantled, cleaned and reassembled the PCV valve and blew out the hard line up to the intake manifold. There was some crud that was dislodged. Then I pulled the plugs and cleaned them. They were quite blackened with carbon and two were wet with oil. We also determined that timing is approximately 6-7 degrees BTDC, dwell is 39 degrees and idle is 650 rpm. Finally, we checked compression which was 1-125, 2-75, 3-125, and 4-50. Number 2 went up to 100 wet but Number 4 did not improve when tested wet. Looks like I have some engine work to do this winter! When everything was buttoned up, the engine started easily. There was still some outward pressure at the oil filler tube but it didn't seem as strong as before. I ran out of time and was unable to take the Willys for a spin. I will do that tomorrow and will let you know how things turn out.    Gary

[GaryM]

SteveKfl, it seems you and my friend had the same idea. I will see tomorrow if the routing you suggest cuts the amount of oil being sucked into the air cleaner. Thanks for the help! Gary

[GaryM]

Hello Russ, Thanks for help. I will check if there is oil in the rad. I do have leaks from the oil pan and I have blue smoke on start up and acceleration. I definitely have blow by happening. I'm hoping that connecting the PCV system as you and Steve suggested will cut down the amount of oil being sucked out of the engine.  Gary

[GaryM]

Hello Oldtime, many thanks for your help as well. I will take/post some photos soon.

[SteveKfl]

Gary, I'm not the master mechanic OT is, just a shade tree logical type, but as a caution, I would suggest NOT driving it without "finding the problem".  It sounds like you may be hydraulicing (sp?) the cylinders with that much oil in the intake system, and the "pressure" has to go somewhere.  With those extreme compression reading variations, I would be concerned of broken rings caused by running it like that already.  Driving it for extended time could get you stranded if it "breaks" under the pressure.  If you do have broken rings, what will the running time do to scar the cylinders???  I would suggest you let OT talk you thru step by step symptoms (if he's willing to) as you answer his questions.  His knowledge is very impressive.  Good Luck!   PS, have you checked your oil bath filter to see if it is filling up with extra oil?

[Rus Curtis]

I'm not a trained mechanic either.  I have to read and rely on manuals and places like here.  This sounds like multiple things and will be a process.

Your wet test on #2 suggests the piston ring.  Your #4 having no change makes me lean towards valves.  I've read that having valves on the loose side (will chatter a bit) is better than on the tight (quiet) side.  IF one or both of the valves on #4 are too tight, they won't seal and allow the combustion to do what it's supposed to:  Push the piston.  Instead, that combustion will leak out whichever valve opening is present.

Since you've pulled and cleaned the plugs (good find BTW) you will want to also check and see if they are firing - especially the wet ones.  My technique is to pull the plug wires and hold them in near contact with their respective plug.  Technique: I pull the boot off the plug while the engine isn't running and let it rest on the plug - just not snap locked in place (otherwise trying to pull through that stuck-on seal will usually not end well), then I start the engine and can easily pull the wire back to observe while not needing to touch anything else.

NOTE: Don't be resting or touching the jeep with any part of your body, while holding the wire as it stops arcing, or you will ground the spark and YOU will be the spark plug - and you'll utter words you didn't even know you knew! 

I observe the arcing spark (can hear the pop too) - telling me fire is getting to the plug - and slowly move the wire boot away from the plug until it no longer arcs.  Idle will either falter (plug working) or have no change (plug not firing).  If you're engine isn't firing on all four, I think it will be obvious.

[oldtime]

  Finally, we checked compression which was 1-125, 2-75, 3-125, and 4-50. Number 2 went up to 100 wet but Number 4 did not improve when tested wet.

Yes as suspected your 1957 has  multiple problems.
As in no easy cures and a full rebuild seems likely.
So as Steve says keep running time to a minimum or you may end up with deeply gouged bores.

Since you have no upper valve cover ventilation; I can supply you with correct pics of how your 1957 system should look.

In the meantime there is only 1 easy thing you can do to improve performance.
Do a  precision valve adjustment.
My written details appear to be missing from the old 3B forum.
But here I give you the link to Doug's excellent adjustment videos......

https://www.youtube.com/watch?v=zRClIFAg8W8
https://www.youtube.com/watch?v=9VrcG6tCQ2k

[Rus Curtis]

Ken,
I think I may have found it:

https://cj3b.info/Tech/Valves.html

Is this the article you referred to?

[oldtime]

Yeah thanks Russ that's the same info in that 3B INFO archive.
Apparently the original Tapatalk post is gone.

Here Gary  Is what I think your 1957 should have ...

NON ventilated rocker cover...


Exhaust valve cover with Posative Crank Valve ties into dual action fuel / vacuum pump.
The brass 3 way fitting goes into dual action fuel/vacuum pump.


The other tube from the PCV three way fitting ties into the RH intake manifold.


In this pic you can see the hose from air cleaner going into the oil filler tube.


Left front view.


Right front view.

[GaryM]

Steve, the air cleaner was filling up with oil. I don't know yet whether the new PCV routing makes a difference. Russ, once warm the engine idles pretty nicely, All plugs are firing strongly. Oldtime, thanks for the clear instructions on adjusting valves. They will come in handy. The photos are identical to my PCV system with one exception--there is no line from the PCV valve to the fuel pump. I have a single action pump and an electric wiper motor.