Any way to test a manual trans before installation?
 

Was at the scrap yard pulling the manual transmission and other needed parts to do a conversion. I'm going back tomorrow to get the adapter plate and flywheel, (ran out of light). I am wondering if there is some basic test (other than turning the shaft) that I can do to feel better about installing this gear box that I know very little about. Also, other than the drive shaft, pedal assembly, shifter, flywheel, adapter, and cross member, is there anything else I should grab for this conversion?

You can pour clean oil through the gearbox and see if it pulls out any metal filings.

4 speed
 

I"ll start with that. Any information out there on rebuilding one of these?

I've got a 100mb copy of the manual tranny FSM. If you PM R Leo, he may still have it on his server for you to download.

Dang, another thing I lost with the great laptop crash of 2 weeks ago.....:( :(

That would be handy to have, I would be happy to host it if it were posted for download.

Try this torrent file I just made. I'll seed it for a few days.

Work the levers manually and turn the input shaft while watching and feeling of the output shaft while in each gear. If it goes in every gear and reverse and everything works for all gears then it is probably okay.

You can also pull the side cover and look at the gears to make sure that they're in good shape. If all is well with this, then it is worth sticking in the car and "giving a go."

i agree with larry.

and will add that the benz tranny is one of the ruggedest ever put in a car. you about cannot wear them out.

before installing it might be worth considering putting in new seals.

tom w

while I am sure the MB tranny is stout, a relatively simple test would be to turn the input shaft while changing gears. it should show that it will go into each gear, and the shaft should turn with the various reductions based on what gear you have it in.
have a friend hold the output shaft to give some resistance, and see if you feel any grinding.
there is sure to be SOME metal filings in the oil, but any big chunks is a bad sign.
John

Well, some tech colleges have a trans dyno to test the student's work after they have done it. Could you ask them nicely if they have one and if they would let you use it for a bit?

It would seem to me that chasing dyno a college with a trans dyno and hassling around with the people and getting this oddball mounted, it would be much easier to just stick it in the car.

I have had several 123 cars with manuals and have NEVER had to touch one except at clutch time. At that time it just came out and went back in. 533,000 miles on one of them and no problems from any of them.

Good luck,

It is kind of an odds thing. I doubt the donar car was scrapped for a bad manual transmission. The worst on a really high milage example is usually worn syncro rings. Still they are not generally scrapped for that either. You pretty well have to put the box into service to find out if they are all good but they probably are. Great time to change the oil as well.
As I stated its an odds kind of thing. If you pulled ten of these manual transmissions out at a yard. Nine out of the ten would probably still be good. The odds are probably somewhat less on their automatics.:D

Link to...Manual manual.

Another thing to check is the output shaft. There should not be any play in the output spider assembly (the piece that bolts to the flex disk) where it attaches to the tranny's output shaft.

nice berries! where is the manual?