zzdcar
Home
/
Reviews
/
Wrenching
/
Here's What The Inside Of A Neglected World War II Jeep Engine Looks Like
Here's What The Inside Of A Neglected World War II Jeep Engine Looks Like-September 2024
2024-02-19 EST 22:13:36

I just yanked the engine out of my 1948 Willys CJ-2A; here’s a look at the innards of that old cast iron hulk called the “Go Devil” that powered America’s troops through World War II.

The Go Devil engine is a 134-cubic inch, cast-iron flathead inline four found in World War Two Jeeps and a slew of other Willys vehicles, like .

Here's What The Inside Of A Neglected World War II Jeep Engine Looks Like

As I plan to take my barn-find junker on a 2,000 mile journey to Moab, Utah to go off-roading on America’s most challenging trails, I figured I’d have a look inside the legendary motor to make sure it doesn’t, you know, blow up or anything.

The first thing my friend Brandon and I did was remove the front grille by just unbolting it from the frame and fenders. Yup, the whole face just pops right off:

That left us with just the radiator, so we unbolted it from the tabs on the crossmember, loosened the hose clamps, yanked the two hoses off, and gently lifted the copper-brass heat exchanger right out of the engine bay.

That left us with a nice gaping hole in the front of the Jeep from which to remove the Go Devil.

We undid the engine mounts, unthreaded a few of the cylinder head nuts, hooked up the load leveler chains, and started yanking the motor up with my hydraulic engine hoist:

Eventually, the war hero was free:

From there, I drained the oil, expecting it to be a clumpy, milky hot mess, but it actually wasn’t nearly as bad as I’d expected from this neglected old farm vehicle.

Then we fastened the motor onto an engine stand and removed the water pump, which had been leaking buckets of coolant onto my driveway. The water pump had quite a bit of surface rust on the impeller, but luckily, it’s rebuildable for about 35 bucks. So far so good.

The entire cooling system was filled with rust, but that should clean out fairly easily.

After removing the water pump, Brandon and I removed the remaining cylinder head nuts.

With all the nuts removed, the head should have just slid right off the top of the block. But, because nothing I do ever goes as planned, and perhaps because of all that rust in the cooling system, a few of the studs were somehow seized inside the cylinder head.

So, in a move I wouldn’t recommend to anyone, I wedged this sucker between the head and block:

This is a bad idea, because the head and engine deck are machined perfectly flat to ensure a good head gasket seal. If you wedge a pry bar between the two, you risk scarring up the mating surface, causing a leak in the gasket.

But I didn’t care, in part, because — — I was blood-boilingly frustrated, and in part, because this thing is cast iron. “It’ll be fine,” my friend and I reassured ourselves as each of us hung our entire bodyweight on the end of that pry bar.

But the pry bar wasn’t enough; even with all the curse words in my vocabulary, I could only convince the head to move about three inches off the block before it just refused to move any farther.

Eventually, I just took an angle grinder to the studs I suspected were causing the holdup:

But even with three studs cut, Brandon and I still had to toil with that darned cylinder head for hours, finally getting it to budge late at night as our muscles began to ache from yanking on that heavy rectangular chunk of iron.

This cylinder head almost broke me:

With that off, we could finally get a nice look at the top of the motor, with its intake and exhaust valves sitting right there on the top of the block.

This kind of engine is called an “L head” design, because the intake charge and exhaust — if viewed from the side — are drawn inboard and down into the cylinder, then up and back out through the exhaust valve, making the shape of an upside down “L.”

The good news is that neither my cylinder head, nor my block had been significantly scratched by my friend and me hammering and prying on that crowbar like a couple of cavemen.

Also on the “good news” front: the engine has apparently been bored out 0.030 inches over stock, as indicated by the tiny stampings on the tops of the pistons. This is great news, because Go Devil engines tend to quickly wear out their rings and bores, since the engines have very long strokes, which drag those rings a long way along that oil boundary.

Further inspection yielded more good news: none of the valves are broken, and rotating the engine by hand confirmed they are all functioning properly. I’m not sure if they were actually sealing properly (and with only 60 psi of compression, I would guess not), but I’ll remove them and give them a thorough lapping. Hopefully that will help.

The cylinder walls also looked fine, with no obvious deep scars, and only a small lip between where the piston rings ride and the untouched bore. I’ll probably hone them anyway and put in a new set of rings, as 30-over rings only cost about $45, and I need to bring my compression numbers up.

There’s more good news on the bottom end, as there’s nothing obviously wrong with the crankshaft, oil pump or timing gears.

And the lobes on the camshaft also don’t appear to be worn down too badly:

Another look:

Sure, there was some sludge on the bottom of the oil pan, but it wasn’t ridiculous, and there were no large chunks of metal down there, thank heavens.

I will say, after measuring only 60 psi of compression in this engine, and opening my transmission to witness a total, I was expecting this motor to totally shot. But it’s not.

My driveway on the other hand:

Comments
Welcome to zzdcar comments! Please keep conversations courteous and on-topic. To fosterproductive and respectful conversations, you may see comments from our Community Managers.
Sign up to post
Sort by
Show More Comments
Wrenching
I Ordered A Carbon-Fiber Roof For My Porsche 996 Turbo And I Might Throw Up A Little
I Ordered A Carbon-Fiber Roof For My Porsche 996 Turbo And I Might Throw Up A Little
I bought maybe the cheapest Porsche 996 Turbo—that’s right, —on the market a year ago, and I’ve mostly been happily stacking miles on the odometer since then. I have been working on making the car my own with a period-correct set of wheels, some extra carbon trim, and a...
Sep 13, 2025
This Restomod 1956 Hyster Forklift Is Certified Fresh
This Restomod 1956 Hyster Forklift Is Certified Fresh
It’s one thing for you to be forklift certified, but it’s quite another thing for your forklift to be certified badass. Most of the forklifts I’ve used at jobs have been unreliable, smelly monstrosities that have been repaired by . This restomod Hyster is definitely not like that. What’s...
Sep 13, 2025
Update: I'm Still Burning Money
Update: I'm Still Burning Money
When I I’d just picked it up from having Subaru BRZ/Toyota 86 front and rear subframes grafted into its crumbling body. When the car came back to me in May, the clock started ticking. I had until mid-September to get the engine and transmission mounted in the car, clean...
Sep 13, 2025
Can You Solve The Mystery Of A Chevy Silverado HD That Kept Blowing Fuse Blocks?
Can You Solve The Mystery Of A Chevy Silverado HD That Kept Blowing Fuse Blocks?
Owners of old are to getting stranded and having to wait for a tow, but drift car driver was caught off-guard when the that tows his mysteriously broke down. The pickup refused to start when and his family were at a drift competition in Englishtown, New Jersey, and their...
Sep 13, 2025
Crappy Jack Stands Can Kill You, But Which Ones Are Safe?
Crappy Jack Stands Can Kill You, But Which Ones Are Safe?
Everyone who has worked on their own car has likely heard approximately one million times that you should and that it’s only safe once that vehicle is resting securely on jack stands. ? Given how relatively simple jack stands are and the fact that they have to do one job...
Sep 13, 2025
Feast Your Tired Eyes On Some Unrelenting Car Repair Horrors
Feast Your Tired Eyes On Some Unrelenting Car Repair Horrors
It’s the end of the day on a Friday. Whether we’re at work or not, your brain is probably elsewhere. So, rather than stare at your inbox, or a spreadsheet or whatever, why not stare into the abyss of this Just Rolled In video, where a guy with an...
Sep 13, 2025
Copyright 2023-2025 - www.zzdcar.com All Rights Reserved