Hello all,

Thought I would start a thread for the general progress of work on my D4 7U. This Cat was allegedly my grandpa's although there is no resemblance to pics. It had one owner between and he told me he swapped undercarriage but he may have swapped more or this could be a different tractor altogether. In any case I am enjoying digging in and plan to put it to reliable working condition and that is it. No plans for paint and cleaning only when necessary. It is a running machine. I plan on opening up the pony and checking the condition of the internals as well as checking the bottom end of the main. The budget is pretty tight and I am working out of my driveway under a tent shelter a friend gave to me. So far I have gotten away without oxy/ acetylene and I have only 100A service to my house and no garage. I have a little MIG so there wont be any proper gouging or welding done here. I have that at work if I can get those parts loaded and taken there on my 8ft utility trailer. Ideally I would like this thing back together by October but I wont become a slave to it. If I'm not enjoying it I will take a time out. I also have a wife and two young ones so my time will be split a few ways.

Here is the progress of the day. I lifted the cover off the transmission. I wouldn't say the gears look great at all but the majority of it should be workable. The first gear that drives from the input to the counter shaft is probably the worst. There has been a fair bit of water contamination in the trans/ bevel/ final drives and it shows. This isnt a production machine so I may very well let this go. Others with greater knowledge and experience feel free to chime in.

The experts will chime in on that water damage, I'd put the top back on, use some gasket sealant on the old cork tranny gasket if it is not badly damaged, fresh oil, adjust everything and drive her.

From my experience of pulling old Cats down that won't ever do a lot of work ever again, is you find yourself going further and further replacing parts that probably don't need replacing, and what started out as a easy 6 hour job pulling the tranny cover off for a look see, becomes a 6 month drawn out drama pulling tranny shafts and final drives to replace all the bearings and seals, a big cost in $$$$, and a big job time wise that requires more than basic tools.

You have a young family, and on a tight budget, if something breaks at a later date, fix it, but in the meantime get her running and working on your jobs, they were well engineered in their day, some would say over engineered, that's why they are still running 80 years later, I've rebuilt a D4 7J tranny and they share many tranny parts with the 7U.

Same advice goes for the pilot motor, keep it simple right now, if the crankshaft bearings are within spec then I'd suggest just pulling the heads off to check the valve seats, de-coke the combustion chamber and to check the cooling passages, rodding them out if necessary, look very closely at the head cooling passages for blockage too, use some thick fencing wire to access all the nooks and crannies in the block and heads, have water trickling into the radiator as you do it to carry any trash out of the pilot motor, using a old speedo cable in a drill works well for cleaning them too, you can do this job in a couple of hours.

Keep it simple right now, or you will end up spending the whole summer working on that D4.
Good luck
Mike

That looks mint compared to what I just cleaned up last winter from a leaky shifter boot on a customers tractor.

www.acmoc.org/bb/showthread.php?27155-D4-going-in-the-shop
Might be some Info from when I got my d4 back to operating condition.
It's a marathon not a sprint, sounds like you have a good plan.
Good luck

"Mike wrote:

The experts will chime in on that water damage, I'd put the top back on, use some gasket sealant on the old cork tranny gasket if it is not badly damaged, fresh oil, adjust everything and drive her.

From my experience of pulling old Cats down that won't ever do a lot of work ever again, is you find yourself going further and further replacing parts that probably don't need replacing, and what started out as a easy 6 hour job pulling the tranny cover off for a look see, becomes a 6 month drawn out drama pulling tranny shafts and final drives to replace all the bearings and seals, a big cost in $$$$, and a big job time wise that requires more than basic tools.

You have a young family, and on a tight budget, if something breaks at a later date, fix it, but in the meantime get her running and working on your jobs, they were well engineered in their day, some would say over engineered, that's why they are still running 80 years later, I've rebuilt a D4 7J tranny and they share many tranny parts with the 7U.

Same advice goes for the pilot motor, keep it simple right now, if the crankshaft bearings are within spec then I'd suggest just pulling the heads off to check the valve seats, de-coke the combustion chamber and to check the cooling passages, rodding them out if necessary, look very closely at the head cooling passages for blockage too, use some thick fencing wire to access all the nooks and crannies in the block and heads, have water trickling into the radiator as you do it to carry any trash out of the pilot motor, using a old speedo cable in a drill works well for cleaning them too, you can do this job in a couple of hours.

Keep it simple right now, or you will end up spending the whole summer working on that D4.
Good luck
Mike

Good luck Mangoman, but heed Mikes advice. You may have mentioned it but is the machine running? Mike has a good perspective as his projects appear to be pretty lean on equipment and shelter but makes up for those using ingenuity and grit.

Anyway, I suggest you make sure you have Operators Instructions Manual; relevant Parts Book(s); Serviceman’s Reference. A few guys on here have manuals for sale as does eBay etc. I’ve seen multiple parts books with slightly different drawings and info fir same S/N so keep your eyes open for those. Out of range serial numbered books can also be useful so you can track various changes from machine to machine. The manuals will save many times the money on your first project.

Hopeful this machine has some affiliation to your grandpa-nice machine.

Best and have fun!
Bernie

"Rome wrote:

That looks mint compared to what I just cleaned up last winter from a leaky shifter boot on a customers tractor.

Rome, did you salvage those parts? They do look quite poor in comparison. I did flush diesel through the compartments so they are somewhat clean.

Yes, most was light surface rust, I dissembled everything and media blasted them.

"d2gary" wrote:

www.acmoc.org/bb/showthread.php?27155-D4-going-in-the-shop
Might be some Info from when I got my d4 back to operating condition.
It's a marathon not a sprint, sounds like you have a good plan.
Good luck

And I thought I was the only one with track tensioner issues 🤣🤣🤣 Some people get a little too ingenious with their tractors. One side the guide studs are missing and it folded the threaded rod like a boomerang. But there are no horseshoes in my undercarriage! 🤣🤣😬 Thanks for posting that.
I have a feeling I wont have it going for the fall but I'd rather run the project longer in time than do a half hearted job and be right back fixing broken stuff right away.

"Rome wrote:

Yes, most was light surface rust, I dissembled everything and media blasted them.

Amazing! Would have never thought that would have cleaned up so well! Nice work.