Military Jeeps, they are Built Differently. What is This Part?

[johngarlick]

It’s a fording valve for deep water, when it’s activated it causes the crankcase to pressurize that pressure is then fed back through a check valve in the fuel pump and transferred into the bell housing transmission and transfer case, preventing water from entering. When it’s not active it works as a crankcase vent into the intake manifold.
Also the thick spark plug wires are to keep down “radio noise” or RFI interference from the ignition as the spark plugs used didn’t have resistors like modern ones.

[DennisRizor]

I love when you ask a question for readers to answer, many of them are actually knowledgeable and give you the correct answer.

[HBSuccess]

I was told by an old Farner who used one as a field truck ... that valve somehow pressurized the drivetrain with exhaust gas so he could drive through the creeks on his property without flooding things out. If frue and if it worked that's pretty ingenious.

[GCTV]

That’s soo smart that it pressurizes the transfer case and diffs under water. We need those same engineers working on new stuff. Now they engineer it to break after a certain time instead of lasting forever

[jeraldbottcher]

I used to work on these. It is a fording vent to pressurize the crankcase when driving through deep water. That is also why the spark plug wires are so highly shielded. The alternator is so big because it is 24 volt and had to supply power to really hungry radios. The closest thing to modern electronics was an upgraded ignition module under the distributor cap, eliminating points.

[rolomaticz]

It's the vacuum controlled PCV valve with fuel tank vent, The cable is a fording bypass valve to pressurize the diffs and prevent water incursion in the gear boxes. Everything is made to be water tight for fording through deep water. So it's all ready for a water fording snorkel if so equipped.

[sidnabavi]

Dave, johgarlik explained it clearly.
One more thing, that 's an early series M151A2, or what the hobbyists call it a " MUTT ", multipurpose utility tactical truck.
It will outlive any of the high priced and complicated modern day vehicles.

[tophauler]

That plug isn't for accessories in my opinion, it's a Slave Receptacle for jump starting military equipment, all military vehicles have them.Also safer than using standard jumper cables.

[colter]

That's a government vehicle there's no emission control on that!

[caucasiansensation]

It's an air check valve for driving through submerged water conditions. It's indeed a breather, but it prevents water from going into the valve cover, bumping up the positive crank pressure

[Laffenguy]

The "accessory" plug is used to jump off a dead vehicle. Keeps Soldiers from hooking cables wrong!

[samrodian]

That clearly was a military Jeep. The 24 volt system would indicate to me as a Brit that along with the odd looking ignition wires, that it was originally a Radio vehicle. The screening of the plug wires inhibits static interference of radio waves. This is very similar to the set up used on British military land rovers from the fifties onwards for the radio vehicles. Usually referred to as "FFR" or Fitted For Radio. As others have said the valve etc does indeed seem to be a pressurising system to maintain positive crankcase pressure to both the engine and gearbox so to prevent the ingress of water under wading conditions. Land rovers rely on high level breather pipes on both axles and engines but this does not prevent water entering any seals of the engine, transfer and main gearboxes nor the axles.

[billchildress]

Those jeeps were waterproof. Everything was sealed against the elements including both axles, transfer case and transmission. Even the electrical system was sealed and vented to the air intake on the engine. That's why you see all those steel lines going everywhere. I have worked on some of the old Willys jeeps that were done in a similar manner, Even the distributor was vented thru the air intake.

[bravowhiskey]

The m151 MUTT. Not really a Jeep, it was quite an odd thing. It was designed by Ford, but produced by GM (under AM General) and later by AMC.

The thing on the manual is a fording valve for deep water crossing. It used crankcase pressure to keep water from entering the geartrain. It should be venting normally and pressuring the system only when engaged.

[seanwatts]

The plug wires and the 'plumbing' for the carb are all part of the waterproofing (already covered). The 'accessory' plug is the 24V plug to jump start other vehicles, usually called 'slaving off'. Today it's a one hole design with a post in the center NATO standard.

[azarellediaz]

That vehicle has those thick spark plug wires because they are part of a waterproof system and the outer metal braid are for noise suppression that prevents interference with radio equipment. The two-prong connector on the passenger side is NOT to power equipment, that is for jump starting the vehicle if the batteries were dead. That is the old design that was replaced by a NATO round connector with a single internal connector for the positive 24VDC and the outside of the post is the negative connector.

[reyzapata]

It’s a VALVE CONTROL FORDING MILITARY JEEP M38/M38A1 NOS.

A control valve is a type of valve that we use to control the flow, pressure, level or even the direction of the fluid according to the need of the process..🙏🏽👍🏽

[timbritton]

There's so much thought and genius in those things that's it mind blowing. I wish vehicles could still be made like this.

[jacobpoucher]

Its a fording valve for water crossings

[roykiddjr]

I drove one in the Army 86-88 13FOX, they tried giving me a Humve, but I stuck every time so got my Jeep back after they called it drop testing, that ment they put a roll cage and lap and shoulder harnesses in them. They ate a true 4 wheel drive, and parking brake is on transmission