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Offline squidtone

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Re: 50 CJ3A "Nuthin' Fancy"
« Reply #165 on: September 14, 2020, 11:06:45 PM »
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.
 
« Last Edit: September 14, 2020, 11:11:39 PM by squidtone »
Dave Miles
Presently: � � � � � � � �
03 Rubicon,
50 CJ3A
Past:
01 XJ Cherokee,
87 XJ Cherokee,
85 XJ Cherokee,
83 CJ8,
81 CJ7

Offline squidtone

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Re: 50 CJ3A "Nuthin' Fancy"
« Reply #166 on: September 27, 2020, 09:50:35 PM »
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.
Dave Miles
Presently: � � � � � � � �
03 Rubicon,
50 CJ3A
Past:
01 XJ Cherokee,
87 XJ Cherokee,
85 XJ Cherokee,
83 CJ8,
81 CJ7

Offline squidtone

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Re: 50 CJ3A "Nuthin' Fancy"
« Reply #167 on: September 27, 2020, 10:00:10 PM »
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.
Dave Miles
Presently: � � � � � � � �
03 Rubicon,
50 CJ3A
Past:
01 XJ Cherokee,
87 XJ Cherokee,
85 XJ Cherokee,
83 CJ8,
81 CJ7

Offline squidtone

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Re: 50 CJ3A "Nuthin' Fancy"
« Reply #168 on: September 27, 2020, 10:05:01 PM »
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.
Dave Miles
Presently: � � � � � � � �
03 Rubicon,
50 CJ3A
Past:
01 XJ Cherokee,
87 XJ Cherokee,
85 XJ Cherokee,
83 CJ8,
81 CJ7

Offline squidtone

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Re: 50 CJ3A "Nuthin' Fancy"
« Reply #169 on: September 27, 2020, 10:12:28 PM »
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.
Dave Miles
Presently: � � � � � � � �
03 Rubicon,
50 CJ3A
Past:
01 XJ Cherokee,
87 XJ Cherokee,
85 XJ Cherokee,
83 CJ8,
81 CJ7

Offline squidtone

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Re: 50 CJ3A "Nuthin' Fancy"
« Reply #170 on: September 27, 2020, 10:18:59 PM »
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.
« Last Edit: September 27, 2020, 10:38:26 PM by squidtone »
Dave Miles
Presently: � � � � � � � �
03 Rubicon,
50 CJ3A
Past:
01 XJ Cherokee,
87 XJ Cherokee,
85 XJ Cherokee,
83 CJ8,
81 CJ7

Offline squidtone

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Re: 50 CJ3A "Nuthin' Fancy"
« Reply #171 on: September 27, 2020, 10:30:17 PM »
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!

« Last Edit: September 27, 2020, 10:40:49 PM by squidtone »
Dave Miles
Presently: � � � � � � � �
03 Rubicon,
50 CJ3A
Past:
01 XJ Cherokee,
87 XJ Cherokee,
85 XJ Cherokee,
83 CJ8,
81 CJ7