1955 CJ5 PCV Question

Cobra99 · Post by **Cobra99** » Thu Sep 10, 2015 7:29 pm

Hello,

I have a 1955 CJ5 that I got running until all of the sudden when I went to start it, it was pumping oil from the oil bath through the carb. It seems to be a PCV issue, but the "Experts" I've talked to don't believe it has one. Attached is a picture of what I believe is the PCV valve. What I need to know if anyone has an idea, how to take it off correctly and clean or replace?

Any help is much appreciated.

Pat

PCV?
https://drive.google.com/file/d/11SaUXp ... sp=sharing

Oil bath:
https://drive.google.com/file/d/1wj2FhF ... sp=sharing

Jeep:
https://drive.google.com/file/d/1c9jLQo ... sp=sharing

BullRun · Post by **BullRun** » Thu Sep 10, 2015 7:59 pm

PCV valves are readily available for a few dollars brand new.

Simply undo and replace.

Located on the lower left side of the block looking forward.

4x4M38 · Post by **4x4M38** » Thu Sep 10, 2015 9:01 pm

Yep, that's the pvc valve right under the manifold in your
first photo.

Are you sure the oil is coming from the air cleaner?

Check to see if you have a vent line from the oil fill tube
to the crossover pipe.

If you have a pressurized crankcase that's where the oil
will most likely come from.

Pull that PCV valve disassemble and clean.

Brian

4x4M38 · Post by **4x4M38** » Thu Sep 10, 2015 9:07 pm

Second photo shows the vent line (rubber hose) leaving
the oil filler and going where ?

If it's going to the air intake between the cleaner and carb
that's probably the source of your oil.

Unless the oil level in the cleaner is too high. It can't be over
the fill mark.

Brian

Post by **wesk** » Thu Sep 10, 2015 9:28 pm

Didn't I give you a link to Binky's CJ5 PCV page?

Here is another good page for the civvy PCV system on the F134. It's the CJ3B page:
http://cj3b.info/Tech.html

http://www.cj3a.info/tech/pcv.html

You will need to remove the two tube nuts on each side of the "T" fitting first. Then you can thread the valve itself out of the plumbing. Make sure flow arrow is pointing in the right direction. With the valve in your hand it should rattle when you shake it. If it doesn't then it obviously is gummed up. One hex end of the valve will unscrew. Document the order of parts removal. Photos are always a good idea. Then just clean it and reassemble.

Post by **wesk** » Thu Sep 10, 2015 10:06 pm

Kaiser Jeep SB 508 dated 1961 covers the breakdown and installation of the system:

The other two pages are in my photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php

Cobra99 · Post by **Cobra99** » Fri Sep 11, 2015 4:43 am

4x4M38 wrote:Yep, that's the pvc valve right under the manifold in your
first photo.

Are you sure the oil is coming from the air cleaner?

Check to see if you have a vent line from the oil fill tube
to the crossover pipe.

If you have a pressurized crankcase that's where the oil
will most likely come from.

Pull that PCV valve disassemble and clean.

Brian

Brian,

It had been running fine for some time until it just got hard to start and when I pulled the hose from the air cleaner to the carb, they were both full of oil. I'm not much of a mechanic, but a buddy of mine said it looked like an issue we'd see if a PCV was clogged or not working. But he had never worked on any older jeeps, just muscle cars. So, before I tore it out and broke something I wanted to ask the guys who would know. I started with so called Jeep experts, who either didn't take the time to listen to the problem or just don't know. I asked them directly if there was a PCV on the 55 Willy's and they said "NO". After doing more research and reading the sites Wes sent me when I joined, I knew there was a PCV valve and should be a simple fix. But I wanted to share and make sure before I messed it up.

It looks like it will be a simple item to uninstall and clean/repair.

I'll let you all know how it goes.

Cobra99 · Post by **Cobra99** » Fri Sep 11, 2015 4:47 am

wesk wrote:

Didn't I give you a link to Binky's CJ5 PCV page?

Here is another good page for the civvy PCV system on the F134. It's the CJ3B page:
http://cj3b.info/Tech.html

http://www.cj3a.info/tech/pcv.html

You will need to remove the two tube nuts on each side of the "T" fitting first. Then you can thread the valve itself out of the plumbing. Make sure flow arrow is pointing in the right direction. With the valve in your hand it should rattle when you shake it. If it doesn't then it obviously is gummed up. One hex end of the valve will unscrew. Document the order of parts removal. Photos are always a good idea. Then just clean it and reassemble.

Wes, this is exactly what I needed. Thank you! Yes, you had sent me the links, which were helpful. But I didn't want to mess it up, so I wanted to be absolutely sure. This forum is awesome with the amount of information available. I really appreciate you annotating the photo, that is very helpful. I'm not much of an engine mechanic, so keeping it simple helps.

I'll let you know how it goes.

Thanks,

Pat

4x4M38 · Post by **4x4M38** » Fri Sep 11, 2015 5:29 am

If I remember my research correctly Willys was one of or the first
automakers to install emission control equipment on their
vehicles. The PCV valve was part of that installation.

It was not designed, as was mentioned earlier, as such, but
as a way to pressurize the crankcase while fording in high
water on military vehicles. This led to two things. The replacement
of the draft tube with this system on all vehicles, as well as
the deep water fording kits on the CJ3V and M38 and later
vehicles.

To enable driving in high water Willys Motors essentially started
emission control on automobile and truck engines.

Wes, if I've misstated feel free to correct.

Post by **wesk** » Fri Sep 11, 2015 11:11 am

Note the date on the service bulletin. Delmar Roos filed for the Willys MB PCV valve patent in 1943. By the end of the 40's several manufacturers were using them. The mandatory requirements show up in 1961 in Cal. and 1962 over the rest of the US. Although designed to solve sealing of internal combustion engines for underwater operation during WWII, they were offered as an option on many brands of vehicles from 1945 through 1961/62.

Some folks confuse the early PCV systems with emission control systems. The primary purpose of the PCV valve is as stated above but eventually it became part of vehicle emission control systems starting in 1961.

For this reason your jeep gurus who said nay to your question may have been thinking smog or emission control systems of the 60's and up.

Cobra99 · Post by **Cobra99** » Sat Sep 19, 2015 12:33 pm

wesk wrote:

Didn't I give you a link to Binky's CJ5 PCV page?

Here is another good page for the civvy PCV system on the F134. It's the CJ3B page:
http://cj3b.info/Tech.html

http://www.cj3a.info/tech/pcv.html

You will need to remove the two tube nuts on each side of the "T" fitting first. Then you can thread the valve itself out of the plumbing. Make sure flow arrow is pointing in the right direction. With the valve in your hand it should rattle when you shake it. If it doesn't then it obviously is gummed up. One hex end of the valve will unscrew. Document the order of parts removal. Photos are always a good idea. Then just clean it and reassemble.

OK, finally got it off the Jeep, it does not rattle, but I can use a straight piece to push on the edges of the brass inside. I don't see a way to get it apart. It doesn't mean there isn't, I just don't see it.

https://drive.google.com/file/d/0B66zfe ... sp=sharing

https://drive.google.com/file/d/0B66zfe ... sp=sharing

https://drive.google.com/file/d/0B66zfe ... sp=sharing

Post by **wesk** » Sat Sep 19, 2015 7:18 pm

You are not looking at your own photo close enough!

Cobra99 · Post by **Cobra99** » Sat Sep 19, 2015 8:21 pm

wesk wrote:You are not looking at your own photo close enough!

Thank you! I figured it out after I posted this, but didn't get back to update. It was pretty black and gummed up inside. Got it cleaned up and reinstalled but now I can't get it to start. I have the battery charger on it right now. Had it fire up for a little while, but couldn't keep it running.

4x4M38 · Post by **4x4M38** » Sun Sep 20, 2015 7:26 am

You may need to clean some oil out of your carb!