Ring gear teeth

[pkozak1]

I know the MB and GPW had 97 count teeth, my question is why did the later engines in the L134 series have ring gears that had 124 and 129 count teeth? And is the rear engine plate that goes between the rear engine and bell housing the same for all the L134 engines (specifically the starter motor mounting hole)/ Thanks.

[Joe Gopan]

All CJ-3A except the late CJ-3A had the 124 Tooth Ring Gear, The early M-38 had the 124 tooth Ring gear. Here's where it gets tricky the rear plate fits only the starter and bell housing for engines with the starter with the 3/8" mounting bolts. The rear plate WO-642237 that goes with CJ-3A starters does not have the bracket for the stay cable, it shares one of the lower bell housing holes. The MB rear plate will work, but it has the separate bracket for the Stay Cable.
Late 1952 thru 1953 CJ-3A had the 129 Tooth Ring Gear and the bell housing Rear Engine Plate and starter were set up with 1/2 " mounting bolts. The late bell housing had a hole all the way thru it for the lower starter bolt and nut.

As long as your bell housing is made for the MB/GPW and you use the rear engine plate with the separate stay cable bracket, and a 97 tooth ring gear, you will have no worries.

[savmag]

Just my understanding on the gear teeth.

A probable reason that the engine designers increased the number of teeth on the L-124 maybe was in order to give more cranking power to the flywheel. by keeping the number of starter teeth the same for example, if you increase the number of teeth on the ring gear you get a lower (higher numerically) ratio thus putting less stress and more cranking power to the starter. It is like the transmission gears.

Otherwise, it could have been simply a change in the cranking motor and flywheel,/bell housing design.

Savvas

[pkozak1]

OK thanks for the info, I was just trying to simplify my build for future owner ( my son, only 4 1/2 now) so he would be able to just stick with MB / GPW info. But since the engine came out of a 51 -55 Henry J car that I was told and is basically a CJ3A engine, I will just keep the flywheel ring gear at 129 tooth and the new matching starter for that ring gear count. It did have half inch bolts around the bell housing if I remember right from disassembly for the starter and one did go all the way through the bell housing. Thanks for the help, will have a complete ( every component rebuilt) rolling chassis by mid November and will just have to concentrate on engine and radiator for next year and hopefully a driveable rolling chassis by next fall.

[Joe Gopan]

It will not fit the MB with the Henry J front plate and bell housing for the late starter.
The MB must have the G-503 Bell housing configured for the T-84 2nd-3rd shift rail . The 97 Tooth Ring Gear is also a must.

[pkozak1]

Ok. So here is the build, I have a T-90 already set back and lowered on the frame with the late T-90 bell housing everything is bolted up, lined up, painted up, rear drive shaft was built at drive line shop. Everything is good to go right up to the rear of the engine, I even did a mock up with the bare engine block bolted up to the bell housing with front engine mount plate bolted to front of the block and had everything sitting in the MB chassis bolted down. You have me confused on the front Henry J engine plate now. How do you tell the difference between the Henry J plate and a CJ3A front plate now. I had the engine bolted down to the MB frame but had to bolt the engine mounts to the plate and then lower the assembly down to the MB frame. It worked everything lined up. Do I need a different front plate for this L134 in a MB frame? I thought all the L134 gear drive engines were the same Originally I wanted to switch to the 97 tooth ring gear and MB starter, now I will stay with the 129 tooth ring gear and starter for that count ring gear in order to simplify my build, just keep all notes and receipts for future reference. Whats the deal with the front engine plate now? Thanks.

[Joe Gopan]

Only worry that you may have is if the Henry J engine front plate is set up for staggered engine mounts.

[pkozak1]

No, it is straight across engine mounts. Did the dry run mock up with the bare engine block bolting it up to the T-90 bell housing and setting everything in the chassis. It was a long hot and humid day in the garage but now I know when the engine is complete that hopefully everything bolts back up again. It took all day as I was working and wrestling everything around by myself. Thanks.

[Joe Gopan]

Remember, the T90 Bell housing is not made to fit the T-84.