CJ-3B Transmission Problem - Shift lever not shifting the gears

Hello Jeep Friends,

I have discovered I have a new problem to tackle. I recently got my fuel pump overhauled and now have my 4-134-F engine quite nicely. Since I had two flat tires anyway I decided to put the CJ up on jack stands and take off all wheels. I thought it would give me an opportunity shift through the gears. I immediately found that although I can move the shift lever freely left and right in neutral, I can't even budge it in a forward / aft direction to try to get into reverse or first gear. I can't make it go into second or third either. I took the trans mission cover off the floor board to get access to the inspection port. I took that cover off also and watched when I pressed the clutch pedal. I think it worked correctly because when I put pressure on the pedal i noticed that the clutch plate would stop rotating. I was never able to get it to shift. Someone told me to spray plenty of penetrating oil down the shift lever area. I did that but I have plenty of oil.

I am assuming this is a T90 but I am unfamiliar with these transmissions. I have a tendency to want to remove the four bolts on the top of the tranny and just pull the shift mechanism out and figure out what's going on. I would like to find good disassemble / assemble instructions so that I will know how to proceed. I haven't gone through all the tech data on the blog yet. I will continue with digging through.

Any suggestions / tips / tricks will be much appreciated.

Thanks for your patience with me long wordy posts.

Chuck

I tried to post this yesterday but I must have not completed the post or something.

I have been digging in the Tech section and found the maintenance manual. I noticed that the very first thing that is done when removing the transmission is to remove the shift lever cover. It is probably a safe bet to pull the 6 bolts and take a look inside. I want to see if the detent shaft is froze up or something.

Chuck

The biggest thing with these transmissions are rust from storage/sitting. If the Jeep was left outside then water will make it's way down the shifter, and into the transmission. If the Jeep was covered up or protected from the elements, then condensation from the atmosphere will attack the transmission parts that are not submerged in oil. Pull the six bolts for the sifter assembly and clean up the action in the shifter. Next look at the gears to ensure that there is not any corrosion on the shafts. slide the gears back and forth to ensure that they move properly. This would prevent the gears from being shifted as well.

Chuck, I am thinking it is a pretty safe thing to do, pull off the shift cover. For sure don't force things. The fact that it is in neutral makes this even easier. The Universal Manual that KW sells has an excellent tear down rebuild for the T90. In fact it is more correct than anything I have found on the Internet. The service manual oldfireguy posted in the Tech Section also does a stellar job.

Take the cover off and do a few things. Disassemble it, and thoroughly clean it up. Replace all the poppet springs. They break ALL the time. This is a great thing to do on any old transmission. Those old springs do some very important things. A broken spring can allow a transmission to lock up the shifter and/or go into two gears at the same time. Two gears at the same time causes "spontaneous disassembly" of the transmission (kaboom). It is not uncommon to find them broken from age. You will need new seals for the shift rails and, possibly some new freeze plugs and maybe even a rail or two. I would take it off, take it apart and see what was needed. You can clean up most of the parts to satisfactory results. For sure new springs. I am guessing it has a frozen shift rail or two, or three. Water notoriously poured down the shifter on these if the boot wasn't on and functional. The rails can rust and seize and often do. It is best to repair it rather than work it loose. You also need to be sure the trans isn't full of water. This is often a blessing in disguise saving you from future heartache if it were to jump into two gears at once. If it has a busted spring in the interlock or rails, it can be tricky to get apart. Nothing requires a great deal of force unless the rails are frozen. Soak it for sure if it is frozen up. Remove the inter lock plunger first.

If the cover is free and shifts fine off the trans on the bench. The shift collar (clutch sleeve) may be frozen on the clutch hub. Try to use a pry bar or large screw driver to shift the trans by sliding the clutch sleeve forward to third gear or rearward to second gear. If that will go, put the sleeve back to neutral and try to slide the 1st reverse sliding gear. You may have to rotate the gears a little to get things to line up. I am still betting the cover is frozen up or has a busted spring.

Thanks Guys, great advice as usual. I did find the online version of the manual you mentioned. Still want the hard copy though. I don't remember if I explained this, but I actually have two Jeep CJ-3B's, only one engine though. I have been wanting to pull the trans that has no engine attached for some time. Looks like now may be a good time.

Thank You Jeep Friends.

Chuck

Bench refresh the engine-less transmission, then swap out the problem child in the running 3B. You'll be better off if you do have water contamination plaguing your primary trans. Needle bearings do not like rust, and will probably give you head aches if not gone through.

Hello Jeep Friends:

Ok Guys, It's been a busy morning. I was able to pull the shift lever cover in CJ with the engine. I was pleasantly surprised to see happy gears swimming in a bath of thick smelly gear oil. It had that heavy gear oil smell that we all would recognize. I can't tell if it is water contaminated or not so let me know how to test or what to look for. See T90-P1. When I inspected the forks and rails, the forks seem happy as well but the rails look like they may have picked up a little corrosion from the condensation or maybe there might be a little water in there. They are still locked up and need a little love. See T90-P2. On the other hand however, the engine-less tranny looked very unhappy. At some point it looks like all the oil leaked but it had plenty of water. The forks and rails are in bad shape too. See T90-P3 and T90-P4. I will go through this one and hopefully return it to great shape. To keep with my phased restoration plan, I think I will remove as much oil as I can, take a close look at the gears and see if I can get them to move. I will fill with fresh oil and see if I can get the drive train rolling again.

Please let me know what you think. Your comments are very helpful to me.

Thanks

Chuck

Chuck,I do not like the color of the lube in the trans. Looks more like mud. Let it set for a bit and the water will settle to the bottom. If it has water in it it will be the first thing out of the drain plug. I would take the opportunity to drain the trans and transfer case. They share the same lube, and the lube you have in there is nasty looking. I would fill the gear train back up with cheep light weight engine oil, spin everything up and drain it out, maybe twice. Then I would run what ever gear oil you choose. There is a discussion on the correct lube in the tech section.

It looks like you have your work cut out for you on the cover. Soak it for a few days in a good rust solvent.

Between the two covers I am sure you have the parts you will need. The poor trans in the 3rd photo... oh my. Probably a good gear case. It would be worth a tear down to see what made it. I am thinking not much.

Sorry, I'm not familiar with that term "Rust Solvent". My first thought would be penetrating oil, but that is usually a spray. What should I use. "Marvels Miracle Oil" maybe?

After you drain the sludge out, I would use kerosene to flush out the remaining crud. Then you can put Marvel's around the gears and synchro. Rustoleum makes a rust converter liquid, but I would be sure to have read the label to make sure it is safe on brass. Clean out drain, rince and repeat.

I am thinking he will need to soak the cover completely for a few days gm. I was thinking a 5 gallon pail full of WD 40 Specialist or something similar. https://www.amazon.com/WD-40-Special...89920259&psc=1

You could rinse the box out with kerosene or mineral spirits. I like to use a cheap thin 10W motor oil for a good wash. If it is really dirty a rinse with mineral spirits wont hurt. Followed by some thin 10 W oil, then the right stuff. I wouldn't put anything else in there. If water comes out of the drain plug, just pull the trans/transfer case out and go through them. Water damage on the counter shaft of the transfer case and the reverse idler shaft and counter shaft of the trans, is very, very common. The water lays down in the bottom. Rust forms but worse, the water provides zero film under the bearings. Water will immediately damage the components under load when it is present. Where dirty oil will cause frosting of the components, water will cause actual metal displacement. Water will ruin it, not just wear it out faster like wrong or dirty oil.

As far as the rusty box... soak it for a week and pray.

Thanks again guys! I was able to get the shift cover free by cleaning and oiling as you suggested. It was hard to get the leverage I needed move the rails so I made a quick jig. See photos below. I was able to shift through all four shift positions in the jig. I dropped the assembly back into the gear box and shifted into reverse and first pretty well. I was not able to get second and third to work yet. The transfer case shift levers seem to work. I want to get that sludge drained now and get the box cleaned out.

Thank You my Jeep Friends

Chuck

That jig would have been perfect for the soap box derby! Great idea, I take it you stood on it while you worked the lever. Good news there. Be sure to disassemble it and replace those springs.

Patent pending on the custom shift tower fixture. Love it!

gm, yes, I still had to stand on it at first but it did loosen up. And yes, definately need to change those poppet springs. The little detent balls are pretty cheep also. Bob, you are giving me too much credit on the patent. It did what I needed it to do. The funny part is that when I was done, I leaned it up in the corner of the garage where I know it will collect dust for the next 20 years. But there is no way I will throw it away.

Ok, Next chapter. This evening before I put everything up, I decided to crawl under and find those drain plugs. I did and took them out. Yep, water. It was in the transmission and transfer case. The oil is very sludgy and is coming out very slowly. It will drain overnight and then I will start the flush.

Thanks Again

Chuck

I like building fixtures as well. Am getting too broke down to crawl around on a creeper to do body work. Then I'm too cheap to purchase a rotisserie, and haven't found any good industrial junk yards locally to source the odds and ends to make one of my own.

Every time I see that picture you have of that jeep body hanging from an engine stand, I grin big time. What a great idea gm. I almost feel like taking the body off to give it a try. It sure is the way to go. I used 4 to 6 strong boy's. It went well enough, but it would have been sweet to just lower it and guide it down under control.

You can do a lot of things with wood. Some good craftsmanship there gm. Nice looking woodwork!

If you like that, check this one out with the wagon body removal. Not as eloquent, but it worked. A lot more cribbing and wishing I had another engine hoist, or a two post lift would be even better.

I Love It GM. I have been thinking of something like this for Phase 2. I may have to make some slight modifications. I love it. Also; That's it, now I know I have to find at least one engine hoist. I thought about renting, but not now. Gotta Have It.

Back to business. I disassembled the worse of the two shift covers (rusty one) and found that one of the poppet springs came out in three or four pieces. I ordered the parts from KW and will get the good one disassembled in a couple of days. I have one concern though, I wasn't able to find the shift lever support spring or the two pins to fasten the shift forks to the rails. Referencing the 53-71 Service Manual, Figure J-14, the two pins are detail 10 and the spring is detail 11. If I can't find the pins I was thinking of substituting roll pins but I'm not sure if they can take the shear load. I would think so but I don't know. The spring is pretty special, Mine is rusty and I really want to replace it.

Thanks you for you help.

Chuck

GM what pictures! Love the rollers carefully bolted on there. A cheap hoarder like no other. Well, maybe a tie. I knew an old professor once that could compete. I'll prove it now. He stored wood for years for "when I build the big house". Well that day finally came. He mentioned it but nobody believed it to be true. Until the next day two dudes come a hauling over my proppity wild eyed and talkative. As it turns out, they'd been called in on a forgotten debt, but stood good for it and turned up at the old guys place to work it off just that morning. Only to find a prehydraulic boom on a non runner wrecker that had been drug into place by a tractor that only tugged five minutes at a time due to waters in the cracked block on it. But I digress. All of those vehicles were stretched out over top of the house foundation, with wood ready to be slid up higher to higher, the ancient rusted boom being the end point and highest. Anyhow, it was roof day because apparently the guy had enough of the walls up which nobody knew and was ready for roofing. So as it happens one of these two fellers were ordered to the end of the boom to let the old wood across the i-beams, the other guy sliding wood up across the rusted out hulk's of gradually taller vehicles. Wood was warped bent due to weathering, but the old guy said he wasn't worried about mold killing him because smoking hadn't yet got him so to go ahead and lay it on across. Which they did until lunch, finishing "the hardest parts,the top story". At eating time, these two snuck out the back way across my place with the story. Eventually the house did get built... Hoarding with a purpose, and converting bet debts to labor. Now that's good stuff!

gm is the man when it comes to ultimate resourcefulness. Economical and safe, using a lot of on hand material. The guy you want in your club when your stranded somewhere!

Definitely buy the engine hoist. I have saved my back many times. It does a great job picking up the trans, transfer case and cross member assembly, and setting the whole ball game on the bench. (something I seem to like to practice)

gm, whats the capacity on that boom at that length? It seems to handle the load well.

Chuck, the roll pins are what is used today. Just make sure they are HARDENED roll pins and the correct size. Roll pins are sized by the diameter of the required hole, i.e. a 1/8" roll pin will fit tightly in a 1/8" hole. No China allowed. That's whats in mine (hardened roll pins). The shift lever spring can be found. If it is pitted, it will eventually break. Here is a good source, https://www.willysjeepparts.com/T90_..._And_Parts.htm

Thank You Bob,

Chuck

The engine hoist is a 2 1/2 ton with the boom all the way in, and 1/2 ton all the way out. It handles well at that length on just about everything. I've had this same one for around 25 years and you wouldn't believe what all it has picked up thus far. It handles big blocks with transmissions attached well, but grunts with a GM 6.2 diesel/trans/transfercase hanging. The best was putting my snow mobile on a shelf for summer storage.... The lift came from Northern Tool and Equipment, for around $180 back then. The only thing I did was swap out the Chinese bolts for grade 8 hardware. I always said that when the ram starts leaking, I would swap in a duel action pump, but it just keeps hanging in there.

I have a very similar hoist. I bought mine from Summit many years ago. That is a good size.

I like the fact that it folds up for storage to a fairly small foot print. Even when I had my bigger shop, floor space was always a premium.

Hello Jeep Friends,

I want to give you an update on my tale of two transmissions.

First the driver: I was able to flush the gear case and transfer case three times with diesel fuel. I chose diesel over kerosene because it was easy for me to get. After the flush I made sure that I could freely shift the gears by hand. I removed the transfer case pan and cleaned out the last bit of sludge. I put the pan back on and put all the plugs back in and filled it with 40 weight motor oil. I replaced the shift cover and cranked it up. Please note this has all happened with the Jeep on jack stands and the wheels off. I was able to shift through all gears and confirmed that the wheels were turning. I feel that I have a workable drive train and I can proceed with the work toward restoration.

Now for the rust bucket: I did a complete disassembly and gained a lot of knowledge from the experience. I was able to inspect all gears and shafts and was surprised to find that some parts seem to be in, not perfect but usable condition. On the other hand some parts will never be used again. I found no rust on needle bearings or the main shaft. Some gears had pitting and some did not. The worst item was the cluster gear. It was very rusty and had several teeth were missing. It needs parts but it is rebuildable.

Thank you My Jeep Friends.

Chuck

Great job Chuck. The best way to learn all you need to know about a component is to tear it down. You'll end up with two good transmissions, and maybe some trading material.