My Willys 3A and 3B Community

3A, 3B, DJ Technical Knowledge Base => "Original"-- Technical Questions, Answers, Observations => Topic started by: TomJ on January 24, 2012, 11:21:03 AM

Title: Foaming oil
Post by: TomJ on January 24, 2012, 11:21:03 AM: Hey guys:

I've noticed since we got our CJ3A running that at the top of the oil filler tube (where the line from the air cleaner tube comes in) there is a lot of oil foam. Is that normal action from the air tube or do I have a bigger problem?

Thanks
Tom
Title: Re: Foaming oil
Post by: Gunslinger on January 24, 2012, 12:54:27 PM: That is definatly not normal....not sure what to check, but I would start with taking the oil filler cap off and seeing if the foam subsides.
Title: Re: Foaming oil
Post by: athawk11 on January 24, 2012, 12:59:01 PM: Tom,
I haven't read anything on that issue before. Only thing I could think of is the air cleaner mesh was cleaned with something that will foam when making contact with oil, and there is residual left on the mesh.

I believe kerosene is recommended for cleaning the mesh.

Tim
Title: Re: Foaming oil
Post by: RussellL on January 24, 2012, 01:28:16 PM: Check your crankcase ventilation. ï¿½If you have a pcv valve it needs to be working or the crankcase will build up condensation in the oil. ï¿½It can happen very quickly too if the conditions are right. ï¿½Some older engines have a road draft tube instead of the pcv, that just vents the crankcase to atmosphere. ï¿½It needs to be open and clear if you have that. ï¿½
Title: Re: Foaming oil
Post by: RussellL on January 24, 2012, 01:37:27 PM: Also, if you have a PCV then you should also have the fresh air inlet tube going from the air cleaner into the oil filler tube so that any air taken out by the pcv is replaced with clean air from the air filter.
Title: Re: Foaming oil
Post by: Bob W on January 24, 2012, 02:27:23 PM: It is normal to have some foam in the top of the dipstick tube if the vehicle is used mostly for short trips. As mentioned, be sure to check your PCV system for proper operation.
Title: Re: Foaming oil
Post by: Oldpeople2 on January 25, 2012, 08:12:24 PM: I had the same white foam 5 years back. cleaned up the pvc valve and replace the head gasket, be good to go ever sence.
Title: Re: Foaming oil
Post by: Chasm on January 27, 2012, 02:48:17 PM: Tom:

Nobody has mentioned it here yet and I am only doing it because of my experience. :(

I had an oily sheen on top of the coolant in my radiator. I also had the foam you mentioned at the top of the dipstick tube. Had that one time, due to a bad head gasket. The last time it happened, it wasn't a cheap fix like a head gasket. Turned out that my block had developed a fine crack. :o Had to get a replacement L-head. Now that the block got rained on a while, you can really see the crack since rust has highlighted it!

Hope your situation is minor, like some of the ones mentioned here!