Blowing oil through the breather
 

So, I have a '90 B2200, with a weber. For once it has been running like its brand new outside of the vibrations, which is most likely a motor mount. However I have noticed there is a trail of 15W40, going down the valve cover, and the breather is caked in it. The hose has a little bit of oil dripping out.

I thought it was the pcv valve, so I swapped that out and it went a way for a while. While changing out the pcv valve, I started up the truck and had it idle for a few minutes with the oil cap off, checking for blow by and nothing. I thought nothing of it, as I stated early it went away. Til now, it has returned. It cannot be the PCV valve. I'll re check for blow by. While at it, I'm thinking of pulling the valve cover and checking the seal for the valve cover.

Would it be wise as well to do a wet compression test on it?

So.....how many miles are on the engine?

Also, are you using one of those cone style "breathers" connected to the valve cover opening? Like this?

https://cimg0.ibsrv.net/gimg/www.maz...6d1fd7ac4c.jpg

If/when the engine has a bunch of miles on it, or other issues that would cause blow by past the rings, then you will tend to get too much oil being pushed through a breather like this, effectively drenching it in oil fairly soon.

I decided to use the knockout on the base of the air cleaner, to direct the blow by back into the carb throat opening to be re-burned like most factory vehicles were done. I believe that this way it keeps the engine and the engine compartment a bit cleaner over time.

https://cimg2.ibsrv.net/gimg/www.maz...fd5cd70b55.jpg

I also have a B2200 with a 32/36 DGEV Weber carburetor, carb installed in 2005. I got the engine professionally rebuilt in 2020. I also have the breather routed to the Weber's air cleaner.
https://cimg5.ibsrv.net/gimg/www.maz...9537ebca79.jpg

That's the exact breather I'm running. Currently its at 155000 miles. Unsure of the engine mileage. The engine was replaced at some time before I bought it, as I was told.
https://cimg9.ibsrv.net/gimg/www.maz...e7be600226.jpg