F 134

Where do you find good quality caps?
But I guess it might not matter as much if we change them every year.

 

Is there an MDXXXX on the head (flat surface above the water pump)? It's pretty hard to find a military block that still has the number. The reason is they surfaced the heads and wiped the number from many of them.

If it was rebuilt and won't rotate you may have found a gem. I made a similar purchase many years ago and turned out it was all rebuilt (new parts and reground crank) but the owner put the wrong rings in. Easy cheap fix. Just disassemble carefully and see what you have.

Careful when removing the exhaust manifold nuts. I would just split them and get new ones.

If it's a military engine, your lucky they replaced the front mount plate. They are different on the military engines. The fold on the military mount plate is reversed and won't mount to the civilian frame.

Edit: I may have confused truck and military engine mount plates. I've had both so I may have confused them.One of them is different.

 

Awesome, but so hard to drive out to visit!

 

I was able to read the engine s/n: MD97861

I wouldn't dare to dream that my stuck engine issue could be as simple as wrong sized rings!

Ha! This is like opening a fortune cookie.

'Nice to get the front mounting plate differences info. I'll have fun reviewing that.

Thanks for the tip on the exhaust manifold nuts. We'll follow that advice.

 

No idea it was a problem.

BTW, it appears you still have the military carb on your engine. Underwater-capable, among other things.

 

That would be highly unusual, I'd say.

An M38 I got last year had a locked engine - in that case it was the shaft of an exhaust valve had corrosion from being in the open position for a. decade or two. Stuck enough to block a full rotation of the crankshaft, but it freed up with some PB blaster and gentle hammering.

 

Ahhh. I should've looked closer.

 

I just got a gallon of Marvel Mystery Oil per another recommendation and will squirt it over the valves and pistons (via a feed tube) tomorrow when I pull the plugs, and rocker cover.
I have PB blaster too. Thought I'd try the MMO first since I have zero experience with it.

 

I have a Solex on my Jeep but it's parked at my brother's until we can pull the engine. I planned to compare them when we get them side by side... or, duh, I could.use pictures from the internet. Tonight I planned to search tonight for what parts are different between the military and civilian jeeps, but don't know if I'll get to it.

 

I got an hour this afternoon and got a first look inside my olive green engine.

First I pulled the spark plugs, mostly to see how difficult they might be to remove. They broke free with just a good grip on a deep well socket; no wrench required. They looked the way plugs might look if not changed for a few years. Plenty of carbon build up. Gap at about 0.034". Internal threads were wet with oil !!!



Next, I pulled the rocker cover. The front driver's side corner of the cover was crushed sometime in storage. I wanted to see if that translated into internal damage. I was also concerned about moisture having entered through the open hose nipple on the little stack (which was also bent over).

First, the gasket looked new.

Second, the nuts and bolts on top of the #1 & #2 rocker assemblies had rusty surfaces, #3 & #4 were oil covered and pristine.

Third, the crush in the rocker cover had crashed into the adjusting set screw on the driver's side of the #1 rocker and bent it slightly, but visibly forward towards the front of the engine. And the forward stud which secures the rocker cover to the top of the engine, was bent sideways towards the passenger side. The entire bottom of the rocker chamber looked oil covered.



Since I don't know much about the internals of this engine, I wondered what I could see if I pulled the exhaust manifold. Two of its studs had been replaced with bolts and were clean and uncorroded. I sprayed all the nuts and bolts with PB Blaster, wanted 10 minutes and tried them with a small ratchet and socket. They all came right off. The exhaust ports all had just a little loose rust laying in them, but no sign of damage from liquid water. I also realized I had no access to anything through the exhaust ports



Then it occurred to me that I might be able to pour MMO into the inlet port, under the carburetor, so I removed it. The carb was extremely clean inside. A new head bolt had been inside the inlet port. No sign of moisture in there.



So... where am I?

(1) I'd like to depress the inlet valves to see if the valves will move. Is there a safe way to do that? Before I do, will MMO poured into the inlet port (under the carb) get immediately to the top of the inlet valves??

(2) I'll if course pour MMO into the spark plug holes and also use a tube to feed it as deep as possible (to the piston tops).

(3) I appreciate that after it turns freely, this engine cannot be run until (at least) the #1 rocker assembly is replaced, and perhaps it's push rod.

 

I just opened the exhaust valve adjustment cover. Wow. Everything looks great & covered with oil !! No evidence of damage to the lifting rod on #1. The photo includes just #1 & #2 so I could crop enough to upload to Beaming Pix.

 

Awesome! Glad to hear it’s looking better than expected! Quick note about the rocker arm… it might be worth trying (carefully) to bend it back into shape. Or atleast start putting your feelers out now for a replacement.

The reason I say this is the #1 and #3 (left-hand facing) rocker arms are a bit hard to find right now.

Right hand facing ones are plentiful, but for some strange reason the lefty’s are kind of scarce and not manufactured new. At least as of a couple months ago.

 

The kind of thing where I picture the US Army still having a giant warehouse full of them, but all right-handed.

 

I noticed the rockers are fabricated from two sheet metal stampings fixed together. It might not take much to straighten it.

And hopefully the tower and shaft are undamaged.

 

LOL

 

Taking a closer look, it seems the bent section of the rocker is confined to the portion holding the adjustment screw. I can imagine putting a long bolt in place of the adjustment screw and twisting the rocker back into position. The problem may be the way that rocker bears on the shaft when twisted. Will twisting it back damage that rocker/shaft interface? Is it already damaged? We will have to wait and see.

 

I meant to say surfacing the block (not the heads duh) wipes the numbers... but cool you still have the intact military s/n. My 53 M38A1 has a F134 truck engine I found on craigslist. It had the funky mount plate and a draft pipe and I had to convert it. I have a military block I may rebuild one day and install to make it more original. It was hard to find.

So if this was mine, I'd be tempted to mount on engine stand, tear down and inspect. Don't want to tell you this is mandatory though.

 

Yea, given the NAVY theme of my build, I certainly like it that I got a military engine. I'm quite sure the seller has no idea what he was sitting on. The more time I spend with it, the more I feel lucky. Finding so many fasteners either new or not seized suggests this was worked just before storage and that storage was pretty good.

I've started searching for parts. I've been disappointed in the past with some Crown and Omix parts (gages). They were both selling the same thing from the same manufacturer. Between them I got six identical gages with identically the same defects, so... How do I identify good engine parts brands? Are all their products as bad as their gages ?