Tech Tips: August 2019 Edition

Gearing Up

I bought a non-running, uncut M151. It was on a farm and had been sitting for about ten years. The engine started right up after I installed new batteries and ignition parts and flushed the old gas out of the tank and lines.

When I backed it out of the garage and shifted into first, the transmission locked up. It seems to be locked in two gears at once. Do you know what the problem is? Something simple I hope. — G. Martin

Unfortunately, probably not “simple.” The rear main shaft bearing may be worn out.

This would let the shaft move laterally, which could allow a two-gear lockup. If the shift lever feels loose, this may confirm that problem. You will have to pull the transmission for repair.

On the plus side, these are simple transmissions. There are also a lot of good take-out units on the market.

With Friends Like These…

I bought a 1943 Willys MB last week. It is my first military vehicle. The last owner told me it needed a new head gasket. I installed one according to the manual and the jeep runs fine now. Oneof my friends told me I have to reset the valves because I installed the new head gasket. Do I? —B. Tedrowe

Either your friend is pulling your leg, or he’s not very experienced with L-head type engines. Replacing a cylinder head gasket on a Jeep L-head engine does not require resetting the valves.

Clean Drill

If you need to drill a hole in some highly visible part of your vehicle, such as the dashboard and want to do a clean job without possible scratches caused by a slipping drill, first put a piece of masking tape over the spot you’re going to drill. Then make a dimple using a sharp punch so the drill bit won’t slip.

Stop The Sag

The door handles on some WWII vintage closed-cab vehicles tend to sag out of their intended horizontal positions because of wear on their shafts. This minor visual defect can sometimes be fixed by simply trading the handles from one side of the vehicle to the other.

WITH THIS RING

Have you ever heard of anyone successfully converting a boat trailer ball hitch to a military lunette ring to be pulled by an M37? Will the commercially available lunette rings fit in my M37’s pintle hook?

My boat and trailer weigh in at under 3,500 lbs. with less than 350 lb tongue weight, so I believe it is no great strain on the truck or its pintle. My issue will be with how to attach a lunette ring of the appropriate size to the boat trailer in a way that assures that connection is up to the loading.

I sincerely appreciate any guidance or experience you or others have on this subject. I plan to haul my boat trailer to and from a local boat ramp a couple of times a year.
—John Gates

Many folks, including myself, have made these kinds of conversions on many kinds of trailers. Of course, you have to check that whatever lunette or ring you find will fit the pintle hitch of your M37. It’s always best to do this yourself rather than rely on someone else’s measurements or opinion.

Military surplus dealers, truck-wrecking and scrap yards are good places to look for used lunettes, or you could query advertisers in this magazine.

How to attach a lunette ring to your boat trailer is a process that only you can figure out.

MILITARY CJ

My Jeep is a 1951 Willys CJ3A, tricked out in military fashion. I recently purchased a nicely made metal rifle scabbard to mount on my windshield. I had to purchase the mounts as well, as when my scabbard arrived it lacked the mounting brackets.

On talking with my supplier, I found that he had few requests for mounting brackets as the MB jeeps apparently came with them. He shipped some straps, but I am at a loss as how to install them.

Do you have a suggestion for proper mounting before I start drilling, burning, or shooting holes in my windshield? I would like it to look as original as possible. Dumb question, from a dumb guy. —Jon Statler

It’s not a dumb question! You’ve just written to a dumb guy who knows a little more about repairing HMVs than restoring them; though I have to say that it’s hard to make something look original when nothing of the sort ever existed.

That being said, here’s my two cents. As you know, the stock CJ3A windshield is much different from those of WWII Willys MB and Ford GPW Jeeps. The most obvious differences are that a CJ3A windshield has a square tube frame compared to WWII Jeeps which had a round tube frame. It is also taller than WWII models, has rounded corners, and a single sheet of glass that doesn’t open.

Your supplier was correct in that most WWII Jeeps had the rifle scabbard mounting brackets already installed at the factory...welded to the inside of the windshield frame beneath the glass. Your CJ3A may have its windshield wiper motors mounted below the glass rather than above, so it may be difficult to really imitate a WWII Jeep. Personally, I’d go for an M38 look. In any case, you’re going to have to use you own ingenuity to mount that scabbard.

An MB or GPW windshield will fit your CJ3A, but since it’s not as tall and has square corners, this could be a problem if you have a top. I owned a CJ3A with a WWII Jeep windshield. The CJ3A top will work, but it doesn’t fit right and looks a bit sloppy. This kind of windshield might be the easiest way to make your Jeep look more like a WWII model, as well as mount your scabbard, but, again, could be a problem if you have a CJ3A top.

Send your favorite Tech Tip or question to Steve Turchet, c/o Military Vehicles Magazine, 5225 Joerns Dr., Suite 2, Stevens Point, WI 54481 or e-mail JAdams-graf@aimmedia.com