50 CJ3A "Nuthin' Fancy"

[squidtone]

I'm finally making some headway on Go Devil assembly. As I mentioned in another thread, I got nervous about my no name valve guide replacements, so I went through days of searching and managed to find Sealed Power exhaust guides to replace the no-namers I had installed. A picture is included below of the inner diameters as a comparison side by side ( the smooth one is the Sealed Power). The Sealed Power are definitely higher quality. I got the new guides in, re-cut the valve seats with my new set of Neway cutters, and touched them up with a quick valve compound grinding. I'm pleased with the fit.
I put in new "King" brand main bearings (I didn't have my crank machined) and checked clearances with plastigage and all looks within spec.
I got the tappets and cam installed (a new Cleavite cam bearing too) also. I am reusing the cam. I never took off the cam gear; I was able to remove and replace the cam/cam gear assembly by putting a socket through the cam gear hole(s) to access the mounting bolts.
I was ready to put in the crank for good but came to a screeching halt when I tried putting in the rear main rope seal. This "rope" seal came with the Fel-pro gasket kit. I was super diligent and squashed the rope into the bottom of the grooves, and used a zillion razor blades to trim the rope in the block and in the cap. I installed everything and torqued down the caps and the crank was stuck solid (I had installed the crank sans rear seal earlier as a test and it spun beautifully). The rope is way too big. There is no way it will squash down. It seems to be kevlar or something; not traditional rope. The thin coating of I presume graphite paste wore off when I formed it too. It's white and not very flexible or pliable. Very disappointed.
I went online and bought a "Best Gasket" 6485 graphite rope seal. (I used the same type on my Pontiac and it has never leaked.) I hope it fits. I remember the graphite rope was easy to form, and cut easily. I want rope because my seal surface on the crank has minor pitting. It's 2.309" by the way. I half wonder if the groove cutting in the block and cap were all over the map in those days?
I'm still waiting for the seal so in the meantime I've fit the pistons to the rods, and installed the new OMIX ADA bearings (the only bearings I could find that were in stock, anywhere). I installed the rod big ends onto the crank (out of the engine) to check clearances this evening and everything is in spec. So I'm happy about that!
The pistons are 0.040 over Keith Blacks and I found a set of NOS Kromex rings on ebay to install.
I'll keep detailing peripheral stuff (coat exhaust manifold with high temp coating, paint engine plate, refurb distributor, etc) and hopefully get rear main seal at the end of this week.
I missed the whole summer for Willys cruising....I hope I can get a piece of the fall.
 

[squidtone]

Got the "Best Gasket" rear main seal. The gasket is made with graphite impregnated teflon strands that are woven into a "rope". Best Gasket Co. recommends installing a 1/16" dowel pin in the bottom of the groove of the cap to keep the rope from turning (which I did). To install, the rope is set on the bench top and flattened (I used a hammer lightly) to thin out an edge which made it easier to squash it into the grooves. It still was pretty tricky to get it squashed all the way down. I used a large socket on it's side to keep forcing the rope into the groove(s). After installing, the ends are trimmed with a specific "stickout" of the ends with a spacer (per instructions) and then dress the ends by folding the strands to the center of the cut ends so nothing gets caught between the block and the cap. After torquing the cap down I measured about 5 ft/lbs (beam torque wrench) to turn the crank. Seems good.

[squidtone]

Got the crank fully installed after checking clearances with plastigage. All mains came in between 0.0015 and 0.002. I'm happy with this as I did not have the crank machined. These are "King" brand bearings by the way. Some of the bearing shell dowel pin holes had to be massaged with a file to fit in the saddles correctly. The pictures attached show the hole being offset from the dowel in the block, and the following picture shows how I filed the hole a bit to fit over the dowel step.
Also I noticed (not until assembly time) that the original center cap is numbered...note the "2" at the bolt head seat, and the front and center caps have notches on the tops that face forward.

[squidtone]

I forgot to mention that before I installed the crank I installed all the rods onto the crank pins to measure those clearances. I used "CROWN" bearings. These all came in around 0.0015".
The caps were all numbered which I thought was done by a rebuilder in the past, but some reading I've done indicates the factory stamped the rods and caps with numbers....which was nice.

[squidtone]

As mentioned before, I cut the valve seats with Neway cutters, and these worked well. I lightly dressed the seats with compound, and then  installed the valves and springs. I set the lash to 0.016". I measured about 8-10 ft/lbs to turn the crank with cam and valvetrain parts.

[squidtone]

I assembled the rod/piston/ring assemblies. The pistons were numbered by Brian (metalshaper) so I of course fit them to the corresponding rods. I fit Sealed Power Kromex rings which have a chromed top ring and chromed oil rings...(the box is old...I don't think these are made anymore). I measured the end gaps of the rings and while I could have left them as they were, I learned that the latest practice in engine building is to gap the second rings a little on the bigger side; this allows the top ring to seal better. Yes, it's absurd to care about this for a Go Devil, but I filed the second rings anyway to achieve 0.017" gaps (from the as-supplied gap of 0.011"). The top ring gaps are about 0.014". So I'll bet I'll gain a good half a horsepower...haha.
The pistons installed easily and I got the caps torqued down. I did not bother with new "pal nuts" on the rod nuts.

I measure about 10-11 ft/lbs to about 30 ft/lbs to rotate the crank/valvetrain/pistons. The 10-11 ft/lbs is when the pistons are all at the top/bottom of travel (no piston movement) and about 30 ft/lbs when the pistons are in the middle of the cylinders (maximum piston speed as a function of crank rotation).

I'm thinking while this is a lot of torque, I think it should loosen up with break in.

[squidtone]

I thought I'd try to put an o-ring in the oil pickup joint. There is not supposed to be anything there, but it seems like a decent idea. I could not find a conventional "english" size Buna o-ring size that would fit. In metric sizes, a 14mm x 16mm would be ideal, but couldn't find anything locally. I then remembered I have some A/C HNBR o-rings laying around in my A/C stuff and it so happens one seems to fit okay. I'm thinking this might just keep some tiny bit of extra sealing when the engine is out of level.....maybe. Eh, I don't think it could hurt.

I bolted down the oil pan, which felt good after all these months of engine parts laying around!

I installed new studs sealed with Permatex 51813 sealant as recommended by metalshaper. I got the head installed and torqued down today. Wow that feels even better!

[OnlyOneDR]

Love the detailed pictures and steps.  You are making good progress!

[squidtone]

I had taken apart my (presumably) original oil pump and all the clearances were in spec, but I decided to really clean it out and took off the bypass plug. I found the spring was broken and someone had stuffed an old set screw in there to (I guess) try to compress the spring to increase oil pressure, or perhaps overcome the problem of a broken spring coil. This was enough of a mess that I decided to just buy a new oil pump. I got a Sealed Power unit from RockAuto, and the box indicated it was manufactured in USA in 2001. I crossed my fingers (hoping that it isn't one of the poorly made ones that seize) and bolted it on.

I took some time to "rebuild" the distributor also. I knocked out the lower retaining ring pin and then installed new bushings (can still find bushings at the hardware store) adjusted the centrifugal weight springs, and reset the spacer to be sure the shaft floats in between the upper centrifugal bracket and lower retainer. There was a precision washer that was too thick which moved the distributor body too high, which made contact with the upper thrust washer and there was alot of wear. I believe the shaft should bottom out in the oil pump and the distributor shaft should "float" with equal distance between the upper and lower thrust washers. I made a thinner washer and got it centered.
I installed the distributor statically, using a multimeter to check when the points open. I wasn't sure where the distributor body orientation is to be, so I made the oil filler go to the 10 o'clock postion. I may re-do this as I think I'd prefer the oil filler in the 2 o'clock position.

The engine went together fine and fairly quickly. A close inspection of the clutch disc revealed it was very worn out, so I bought a new clutch. While waiting for that, I decided to make a double bolt bracket for the top two engine to bellhousing fasteners. I had a whizbang of a time trying to loosen them since you need two wrenches and it's so tight there on the driver side. I realized what that hacked out big hole was for next to the gas pedal (that I welded up during body resto) on the firewall....access to that driver side engine bolt! So I made a template and cut up a piece of 1/8" steel plate, made a jig, and welded the bolts and metal together. Now I need only one wrench to tighten down the top bolts. It worked nicely!

Finally, shockingly, I was able to adjust the exhaust flap weight and got it adjusted as it should be for cold starts. I was even able to reuse the sheet metal tab used as a stop for the end of the bimetallic spring. It's odd what survives and doesn't in these old Jeeps.

I painted the engine, and it looks better than it did.

 

[squidtone]

Greetings.
It runs.
I finished installation of the engine into the Jeep. I waited for a nice weekend day and started it with not too much fanfare. I had a silly gas leak, and after I got it running, I experienced a coolant leak at the manifold stud at the front. It took three tries to seal that up. I ended up useing "high performance" Permatex stuff for that.
After that I have seen no leaks. The rear main seal is also dry.
I ran the engine at about 2K rpms for about 10 minutes and then took it for a spin. I noticed it has a bit more power. I reset the valve lash when I took the manifolds off to re-seal the leaky stud, but I still have one ticking noise. Not a big deal and I will investigate that soon. I've put about 50 miles on it and all seems very well.
While I know there are scads of Willys videos out there of engines running, I'm adding one more just to show that a cracked block can live for another day.

I posted it up on youtube:
https://youtu.be/5PjGPQ6Z7ZE

I've started a somewhat major suspension refurb on my 2003 Rubicon, so that might keep me busy for a while keeping the half cab resto on a back burner for the Willys. But I"ll post updates when I get to that!
Thanks,
Dave

[SteveKfl]

The smile on the driver's face says it was worth it.  Congrats!

[athawk11]

Looks and sounds terrific!

[Rus Curtis]

How sweet it is!  Great documentation!

[squidtone]

The driver at the end of the video is my daughter...She LOVES Jeeps. She used my Rubicon during her teenager years. A month ago, she ordered for herself a 2021 Wrangler Willys Jeep. She had to order it because she wanted a 2 door with manual transmission. Dealers don't stock that sort of thing anymore. I'll take a side by side picture when she gets it!

[SteveKfl]

Well you raised her right.  She likes Jeeps and manual transmissions.  You go girl.