My lengthy Borg warner T18 rebuild thread

hi Wheelie:

Thanks a lot for your detailed description of the rebuild process, it's been hard to find such detailed and complete reference online. I'm trying to rebuild my t18 on my 1972 Ford 250 too. I was wondering how you are going to assemble the input/output shaft ball bearings back ? ---- I see that you use a puller for the disassembly process, which is similar to what the factory manual suggests (they use a special puller, part number t75l 7025B, included in the set t75l 7025A ). The factory manual uses the same custom tool to assemble the bearings back. from the very limited description I could read from the manual, it seems that the 7025B tool, with an adaptor, screws onto the inner thread on top of the shaft, hence fixing itself to the shaft, then uses a screw to push the bearing downward the shaft.

a lot of other online descriptions of the rebuild process suggests dropping down the counter shaft and then "slide out " the input /output shaft. this is rather confusing, I think both the inner race and outer race of the bearings are designed to be press fit, if they "slide out", that means the holes on the case are too big due to multiple assemble/disassemble processes.

Regards
Ted

 

The bearing inner races are a press fit on the shafts. The outer race is a slip-fit into the case. They do get stuck sometimes and hang up in the bore. Heating the bearing up to about 300 degrees in a toaster oven or on a hot plate allows them to expand and drop right on. you've got to be quick though and make sure all oil is off the bearings. The other way is with a piece of tube and drive them on.

 

Thanks Nickmil.

I guess that since the assembly process is a reverse of the disassembly, we should put the shaft into the case and aligned, then heat the bearing, then slide onto shaft? but then the outer race is enlarged too, so the outer race won't fit into the case bore hole ? or are we able to pull the shaft out long enough so that the inner race can sit on its final position on the shaft before the outer t starts to touch the case ?

sorry for these cumbersome questions, I'm trying to fully run through the process in my mind before actually taking down my trans, kind of like a "virtual dry run", so I have a higher chance of success.

Ted

 

I figured on driving the bearings back on when I get to that point.

My drill press is a table model and not big enough to drill the holes in the ears of the transmission. I could hand drill them but, this is a good excuse to get a floor model drill press and sell the table mount one.

 

OK cats. It's been too long and time to get back at this. I am looking at one more used drill press and if it doesn't pan out, I'm taking the set up to the machine shop and having them drill the two remaining holes in the t18 case, then having a piece of Al welded into the bell, around the new hole. I'll just have a pilot hole in the bell at first, until the piece is welded in. Then it will be drilled to the correct diameter and tapped.

Told ya this was gonna take a while..................

 

Any luck finding another drill press so you can drill the ears on the t-18? Just curious

 

No. Can't find one that suits me. Dropping the bell and T18 case at the machine shop tomorrow after work. Pics when I get it back. Then I'll review my work to get back into the swing and, then dig back into it.

 

Got the bell and case back from the machine shop today after work. He welded in a bung for the bottom right hole and did all the rest of the drilling and necessary tapping for me. He just had to drill the lower left (driver side) hole in the ear of the tranny case to match the threaded hole that exists in the bell housing, then weld a bung in for the lower right (pass side), drill the ear on the case, then drill and tap through the bell and into the bung. Not the best weld job on Al but, it will do. I was going to take it elsewhere to have the welding done but, he said he could do it and, I thought it better to let one guy do all the work.

I'll start refreshing my memory this week and, hopefully get back to the tranny rebuild and final assembly shortly. Hopefully. Getting cold outside and in the garage.

The bell, T18 case and adapter all bolted together and home from the machine shop.



The inside of the bell. The new hole and bung ended up right in the webbing. Sort of figured it would. Not the best shot of the bung he welded in. It's about 3/4 or 1 inch long. I can take a better shot of it if someone wants.

 

Hey wheelie,
Sorry to ask, but If you could get a better shot that would be great?

When I try and do this hopefully next month, I want to be able to explain and perhaps show him so the local guy I know can't mess it up. I have to always check his work soo...

Looks good too!

 

I had envisioned more of a plate, welded to the inside but, ended up with this. I suppose it will be fine. Just not what I had imagined.

 

I am getting ready to do the same thing that you did. I read on novak to just drill and tap a hole. Nobody said anything about welding in a plug. Do a lot of people do this or is it something you had just recently thought of?

 

I've read about it and had it suggested by several. The bell is pretty thin in that area. Notice the places where the factory holes are. Also notice the area where the new hole and bung is. It falls right on the cast web inside the bell. Odd place to tap a hole.

 

I would agree Dave , Not the best welding job.......hopefully it does hold , that fix has been done many times before on the old original OEM BOP Bell housing with success ..........looks like it was a little cold and the material was also dirty..........I personally like the aftermarket Advanced adapter Bell Housing.......shown on the left........much stronger and drilled for multiple patterns. These are both spares if anyone has an interest.

 

I don't claim to be a welder, an ASME inspecter told me that I could be certafied, take that as you want...
That weld job is about the worst thing I have seen, It sort of looks like some work I did back in the 60's.
I'm happier working with wood but I still seem to end up with some burn holes in some of my clothes.
Ahhh, the joys of owning an old CJ.

 

I did notice that If I tapped straight through, it would be half on the inner ridge and half off. I don't know how strong the plug would be either welding it to the cast, probably stronger than just tapping the hole though.

 

To bad I have a sbc I would buy that advanced adapters bell from you.

 

I sent the picture of that weld to a metalurgical engineer friend of mine. "Nah, I don't see a problem with it, I saw lots of welds like that in 3rd world countries."

 

OK. So, I separated the bell from the case this evening. Planning on having the butch weld fixed. In the meantime, I think I can start putting this thing back together. Instruction manual says start with the countershaft. Install roller bearings, etc, install counter shaft, then onto the reverse idler. I'll be figuring out what I'm going to use for a pilot shaft and how o hold the thrust washers in place.

Cold in the garage, which may be good for assembly (cold petroleum jelly) but, not so good for me. First heating attempt isn't working out so well. We'll see how this effects my progress.

 

Dave, Hard to tell what you have on that weld........I would first take an aluminum burr on a high speed tool and grind it back a little and clean up what's been placed on there......I mean if you get back to the bung and there is solid metal / weld holding it on you may be fine.......either way whoever re-welds it will take it back to good material anyway......make sure he uses some acid to clean the weld zone.

 

Thanks. I will tell him to make sure it's acid cleaned and warmed up. A friend put me in touch with the guy who is supposed to be a pro. We'll see. I just don't want to chance it and, after all the negative feedback, I am not comfortable with it as is.

Any tips on assembly/installation of the counter shaft? What to use for pilot shaft, etc. Thinking of trying to find a piece of PVC pipe or wooden dowel rod that will work. Not sure about the other little tool for holding the thrust washer in place while installing the shaft.