P.C.V Baffle

Discussion topics on Willys Overland M series vehicles

Moderators: TomM, Moderator, wesk

Post Reply
User avatar
horse
Member
Posts: 218
Joined: Sat Sep 07, 2019 6:00 pm
Location: Yorkshire U.K.

P.C.V Baffle

Post by horse »

When I was setting the Tappits I noticed the ventilator parts did not have a Baffle on the body fitted to the side valve cover.
I checked TM9-1804A page 68and it does not show one.
Looking through the parts lists on a GPW it does show Baffle GPW 6762 WO-630298.
I am interested why this Baffle was deleted. The only related threads was the possibility of the Baffle becoming blocked.
Another post said there was a factory instruction to remove the Baffle but I am unable to find this.
Does anybody know the reason or have a copy of the factory instruction?
Horse
1952 M38
RonD2
Member
Posts: 2065
Joined: Wed Oct 01, 2014 6:00 pm
Location: South Carolina, Dorchester County

Post by RonD2 »

Image
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari

User avatar
wesk
Site Administrator
Site Administrator
Posts: 16413
Joined: Sun Apr 03, 2005 6:00 pm
Location: Wisconsin
Contact:

Post by wesk »

That service bulletin only applies to the porous screen on the models 4-63 & 2WD's. The fixed baffle on the L & F 134 in the 4WD Universal type jeeps is not addressed here.

The ORD 9's 1951 and 1956 for the M38 never had a screen or baffle at all. It was obviously not a good idea and was discontinued on the later engines like the M38. Note that the service bulletin's date is 1948. 2 years before the M38 was produced.
Last edited by wesk on Wed Jun 12, 2024 10:43 am, edited 2 times in total.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
User avatar
4x4M38
Member
Posts: 3487
Joined: Thu May 29, 2014 6:00 pm
Location: Texas Hill Country

Post by 4x4M38 »

Reading into the page, it seems the better fix would be to install an oil filter.

🤷‍♂️
RonD2
Member
Posts: 2065
Joined: Wed Oct 01, 2014 6:00 pm
Location: South Carolina, Dorchester County

Post by RonD2 »

wesk wrote:That service bulletin only applies to the porous screen on the models 4-63 & 2WD's. The fixed baffle on the L & F 134 in the 4WD Universal type jeeps is not addressed here.

The ORD 9's 1951 and 1956 for the M38 never had a screen or baffle at all. It was obviously not a good idea and was discontinued on the later engines like the M38. Note that the service bulletin's date is 1948. 2 years before the M38 was produced.
Porous screen? Is there any other kind? :D
What "fixed baffle" are you referring to Wes?

My dipstick has what I'd call an "anti-sludge" baffle on it about half-way down.
Can't think of any others in the ventilation stream.

Maybe wrong, but it looks to me like they figured out the "crankcase ventilator screen" was a bad idea (or at least, unnecessary) on the L134 no matter what model it was installed in.
It makes sense that once they deleted it in 1948 it wouldn't appear in any subsequent year model (including the M38) documentation, manual, or bulletin.
4x4M38 wrote:Reading into the page, it seems the better fix would be to install an oil filter.
I can't quite connect those dots with the bulletin, but believe having an oil filter is always the best bet for engine life.
Won't an oil filter also "sludge up" the same way under the same driving conditions they describe?
I think Willys sold it as an "option" for $3.25? :lol:

I was just trying to answer Horses' question. 8O
Couldn't stop myself. You'd think I'd know better by now. :lol:
Last edited by RonD2 on Wed Jun 12, 2024 1:25 pm, edited 2 times in total.
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari

RonD2
Member
Posts: 2065
Joined: Wed Oct 01, 2014 6:00 pm
Location: South Carolina, Dorchester County

Post by RonD2 »

Just so we're all on the same sheet of music, this is a photo of the WO-630298 ventilator baffle screen that Horse is asking about.

The Willys Service Bulletin doesn't give a part number but I assume this is the part they're referring to. Reasonable?

I see several vendors have stock for $10-$12 each if you change your mind and want one. :D
Image
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari

User avatar
horse
Member
Posts: 218
Joined: Sat Sep 07, 2019 6:00 pm
Location: Yorkshire U.K.

Post by horse »

Excellent, thanks for the information.
The photo for the Baffle is the same as I have but will not be now fitting.
Horse
1952 M38
Post Reply