Different PCV valve location

[Frank Elder]

Odd canister on the water neck, and tightly sealed oil filler tube with pcv valve installed in it that runs to the carb.......as they swing around to the other side there seems to be another line coming from the draft tube connecting to the intake is it a pcv line or a vacuum line? I can't get a clear view of the draft tube to see if it has been removed or not.

The regular vacuum port on the intake is plugged.

 

[kencombs]

Looks to me like the line fro the oil filler tube goes to the carb, to pull filtered air into the crankcase.  The draft tube looks to be modified and a PCV valve installed there and plumbed to the intake.

 

No ideal what that thing is on the water hose.

[Frank Elder]

So okay.... found another video with the same sealed crankcase, these set ups are for M37's so they can ford creeks and what nots without hydro locking the engine.

 

[kencombs]

Yep, that one even has the military ignition and generator connectors.  Water resistant if not water proof.  Uncle Sam paid dearly for those.

[JBNeal]

I did some testing on a Power Wagon PCV setup that was based on basically several technical service bulletins that are in the Downloads Section...there is a vacuum tube from the oil filler tube up to the base of the carburetor.  Just plumbing a PCV valve from the draft tube port to the intake manifold stopped the exhaust fumes that leaked into the engine compartment from the draft tube, but some fumes would be visible from the oil filler neck filtered cap at shutdown.

[Adam H P15 D30]

This works well for me, no oil loss or fumes...  Cut the tube off, flip it upside down and seal it to the block with an o-ring.

[thisoldtruck]

 

That's exactly the PCV valve system on my truck!  All the Power Wagons  were set up like that.  I don't know what that thing is either on the radiator hose in the first video.  The main reason was most of the time, the truck stayed stationary and didn't move while the engine ran providing power for some application, so a draft tube would be worthless ventilating the crank case.   The M37 were designed to ford in 28" of water, and with little modifications to ignition system, a civilian truck could do the same..

 

Now, the Power Wagons also used a very similar PCV valve for power brakes hooked to the power brake booster as well. 

Edited February 22, 2019 by thisoldtruck

[Frank Elder]

Thank you thisoldtruck.