Hi My Dad purchased a Michigan 175G M III wheel loader that had several issues (leaking engine, transmission and torque converter oil, one rear wheel at a slight tilt). Being a farmer with a good knowledge of mechanics, he tackled the job of pulling the powertrain and fixing the leaks. This is the object of ongoing concern. The torque convertor has been out three times in order to fix a leak and is still leaking even though all the seals and gaskets have been replaced. The site of the leak is a threaded hole on the underside of the convertor. Upon talking to a mechanic where Dad purchased parts, he was told it could be a wet or dry converter. I understand, a wet converter will leak a certain amount of oil but it is recirculated to somewhere in the system to save the oil. This machine has nothing there to catch and recirculate the oil, thus it ends up on the ground. The engine in this machine has likely been replaced with a truck engine, as it has a 6V92 with a Ford front motor mount and a jake brake. Our way of thinking, is that the original machine must have been set up in such a way that the oil coming through the converter was captured in the housing and sealed away from the engine to be captured and reused. With the truck engine in place, there is no seal to the engine. Oil would be free to fill the housing and spill through the starter or between engine and torque converter. What we are wondering is, what is the original machine set up like as far as catching this torque converter oil to be recirculated? Is there some major component missing from this set up? Is there perhaps just a hose required from the threaded hole in the bottom of the torque converter to where? I would really like to get to the bottom of this mystery as my Dad is 84 yrs old and really doesn't want to pull the converter another time. Any info would be greatly appreciated and if a service manual is available somewhere, I'd like to know about it. I do have serial numbers of the machine, transmission and converter if that will help in any manner. Thanks for any help..
The 175 III originally had a wet sump convertor. If the convertor was replaced with a new one, the new convertors were made for dry sump applications and if they were to be installed on a wet sump machine you had to remove the inspection plate and remove a 1/4 " pipe plug for the wet sump to vent properly then the threaded hole at the bottom of the case would be plugged. If the convertor was to be used with a dry sump there would be a drain back line from the threaded hole in the bottom of the case to the transmission sump for the leakage oil to excape back to the sump. without the proper sealing of the engine and stater you probably should install the drain back line and run it as a dry sump. Remove the inspection plate and make sure that the 1/4" plug is in place.
Thanks for your info, we will check that out. Is there some way to find out using serial numbers, if the original converter is still in place? Is there anywhere that we can find pictures or diagrams of where the lines terminate?
Don't have the build sheet on that old of a machine. The Convertor model should be C-8502. Originally the drive gear bolted to the flywheel was steel, they were quite noisy, replacement is a fiber drive gear. The drain back line goes from the bottom of the convertor housing to the transmission toward the right side of the machine just above the oil pan. There should be either an "O" ring split flange or a pipe plug in the case, you would have to get fittings for the convertor drain and make up a hose. If the transmission has a split flange port just make the hose with an "O" ring fitting on that end to match the size, if it is a pipe thread, use a JIC to Pipe fitting and a JIC end on the hose.
Great, thanks, that is the model of the converter in there now so it must be original. Its coupled to a model 3421 transmission. With the engine being changed, its hard to know how much more has been changed around. I am of the opinion the machine was pieced together to move and then sold. I do believe that when Dad had the converter apart, he did say there is a metal drive gear in it. Will check out the rest and hopefully solve the leakage problem once and for all. Thanks again for all your help..
There does not appear to be any sort of opening in the transmission, no plugs or flange. What are your thoughts now? Is there any other place this oil can be routed through?
Mr Oldseabee: I decided to go over to see the loader myself so I would have a better idea what I'm talking about. I saw the flange you must be talking about in the lower right hand corner of the transmission. There is a line connected to it, a metal fitting then a rubber hose clamped over a metal pipe running to the underside of the converter, actually a slight bit off to the left side of the converter. The hole where the oil is leaking from, is just above the differential, in what I would call the bell housing. Dad says its still part of the converter. The threaded hole looks to be about 1 1/4 inch diameter and sits just above the differential. Now that we have that clarified it may open some new doors on what the solution may be. Thanks again for all your help.