Well even after years and years of searching the classifieds rubbing elbows and networking I've been stuck in this "transmission rut" since the idea of this project began...maybe I'm a sucker for punishment but I wanted an early driveline...I'm looking for as near to the experience guys had 60-70 years ago as possible...so for me that includes a manual top shift trans but I've now conceded that the 4spd crash box I have is a no go...these are my next best option...ugh This as a 1950 side shift 3 spd. in good working condition and a '42-'50 78 case ...what I don't know is how to get the rusted gobbldegook out of the case (while saving the input and output shafts) nor if the gears/guts from the other trans will go in it? btw Van Pelts is curiously silent on the subject... Oh and now that I've been fooling around with these transmissions what the hell is that god awful stink that is following me everywhere? ....dead dinosaurs
Differential oil can get pretty rank after a while. Transmissions also used whale oil at one time, before ATF was discovered. Maybe that's what's going on.
so how about it... can '49+ gears go in a 78 case? or am I barking up the wrong tree... again @Mac VP?
Old Dexron ATF gets pretty rank in the Bottle...some things certainly have shelf lifes, but yeah, gear oils for standards and rear ends aren't the most fragrant by any means...the nitrile gloves are a damn good idea at a minimum... I farm out stuff like that...and my knowledge of what's in those shells is minimal at best... You have my sympathy...
I’m working on the transfer case from a ‘42 Jeep and the smell of the old gear lube is forever – I can still smell it on my hands days later, despite several washings. Good lube though, everything inside looks new.
Chisel all the gunk off and let it soak end up in a bucket of cleaning vinegar for two weeks. Support the bucket so that it can,t fall over. You will be surprised how it comes apart. You can re-use the vinegar too. Don,t use a aluminium bucket
Man the one looks a but tough but maybe some will be salvageable. Well the early side shift gears will fit into the top loader and yours is the later side shifter I will check . I believe the later as you have uses a different main shaft. I know you will have to use the whole gear set as the tooth design changed Even if it’s a early case they fit but tight on the bottom. Some guys grind clearance so you can put her together easier. If it’s a 78 case they will slide right in and you said you have a 78 case...
On a slightly different note. some years back a friend put together a nice 53 F 100. Flathead V8 with a toploader trans. He went with an 86 ? three speed with O.D. Still a top shifter with a little different shift lever showing. Much better on the highway.
Yes vinegar was my first thought too but not sure if its too corrosive as I need the input and output shafts to be reusable...
I'm pretty sure you'll be okay with the vinegar. I've used citric acid blend on wrenches, seat slides and stuff like that, and they were okay. Vinegar is less "invasive", can't remember the right word!
eventually I may go open drive but the first edition will be a model A rear axle w tt ...so I need the early case
Any reason you can't find another 78 case? Or early Ford 3 speed internals? They're not that hard to come by and would save a lot of effort over trying to salvage the input and output shafts...
Well I started this project in 2015 and here I still am...I was going to say money but fact is I have never seen one for sale...maybe it's an inner circle thing lol A buddy who has more $ finally got someone to rebuild him a '39 but he was years in the searching and part collecting...even supplying all the parts I think it cost a grand just for the rebuild
The insides look rough, but soak it and it should be able to come apart with ease, Vinegar does work well, i have used evaporust as well, it works well but not on caked grease. my method is to fill the case with lacquer thinner or varsol, to dissolve any caked up gunk in the bearings. Drain then fill with Evapo rust or vinegar to eat the rust. drain then disassemble. The gear sets will not swap directly into it. there may be some parts interchangeability but not the main gears. The bearings are loose needle bearing in the car trans i believe, the track trans still uses the caged roller design. i would recommend, tearing the 78 case trans apart. Soaking all the gears and shafts in evaporust, and see how they come out. If the teeth are all black and pitted, i would not recommend using them. the teeth of the gears have been weakened from the rust and well, these trans gears are not exactly strong to begin with. the gears and bearing are not hard to find to replace. i bought all NOS gears and syncos and thrust washers for the last one i built and had less than $300 bucks in them. by scouring E bay. Then most important part of rebuilding an early Ford trans, is getting you end clearances right, i like to set them up on the tight end of the range. Also completely disassemble the shifter top, put ne springs and balls in the detents and polish the fork shafts. I like to shim the springs for the detents with tiny washers to increase the spring load on the detent balls and sometimes I even stretch the springs a little. It makes for a much more positive feeling shifter.
some transmissions in the classifieds here this 39 and a 40 that you can use the guts out of.. https://www.jalopyjournal.com/forum/threads/39-ford-transmission.1242549/ https://www.jalopyjournal.com/forum/threads/1940-ford-transmission.1242607/
They have a parts list that goes later and will tell you what will interchange. They cover the open drive line trans you show and which parts will fit in their gearset information. I don't think the passenger car parts will fit but would be worth calling them and asking.
Thanks @Moriarity ! I appreciate it but can't imagine what shipping a whole trans up here would cost!..on the bright side the HAMB has connected me with an elusive part that I'm going to have to ship...just don't tell my wife! he he lol
I asked a very similar question in this thread https://www.jalopyjournal.com/forum/threads/early-ford-3-speed-compatibility.1229954/ Mac answered me there, his answer may be what you're looking for.
Thanks @Aaron D. I had found that previously during my searches but wasn't sure if the "78 case" nomenclature also included the later side shift trans...if I understand it he's talking about 27 tooth trans. which case they are interchangeable if not then only the synchros from the '49 -'52 car trans can be utilised???or am I misunderstanding and he is saying count the teeth it might work? I would prefer car gearing in the truck trans case but can't use the long tail open drive trans for my project...is it worth pulling this trans apart for only the synchros? good shape or not I don't think anyone else would buy it...the reasons I think it is a car trans. is the steel bellhousing and tiny clutch it could be truck but its hard to get info on the late trans...as you can see in the pictures it's visually hard to differentiate