Neil, Is the hydraulic tank with the D-4 on it then a LaPlante-Choate accessary including the pump?

Thanks

as for oil use a detergent they were made to use it!

the delo range of engine oils were originally developed by standard oil company and caterpillar for use in cat engines cat made the test engines for them. delo stands for diesel engine lubricating oil.

personally i would use delo gold 15w40 in the engine. a multi grade is superior in most cases to a mono-grade oil. look up your chosen oil company's product recommendation for the machine. your operating environment will change your choice of oil grade. if your in a primarily cold environment you may want to use a 10w40 rather than 15w40

The original owner would not have used Delo, but I hope subsequent owners did. At least it was likely available after WWII. I was never a logger or farmer that used diesel engines. I don't know their likely mindset, but mine was buy what ever oil was on sale when I started driving in the 70's. Even way back then "non detergent" was not an oil, that was common. My thoughts about it then, were it was for old cars and old lawnmowers. My 1st car was a 1937 Chevy Deluxe coupe. That motor was full of gray sludge. This dozer is older so I don't know yet what I will find. The 1st car I drove to college was a 1940 Ford Deluxe Coupe. It had an early 50's flathead that was cleaner, but still had sludge in the pan. My 1st diesel was a 6.2 in a Blazer. It was sitting a long time, long enough for squirrels to pack Filberts up the exhaust, and when I dropped the pan on it, to change the rear main seal, there was a small amount of sludge in there after multiple oil changes. I expect this dozer diesel to have some to a lot of sludge in it. I expect I will use Delo 400 in it and just change it often. That is considering it runs!!

Thanks Neil, that's interesting! When we went to lower the blade once the dozer was on the trailer, it didn't go down with the jack after the chains were removed. So we raised the jack back up to hold it from falling, which would not have been good for the trailer, it has a soft deck already. We had the blade up high. I 1st tried pulling up on the handle until someone said rotate it. The blade lowered nicely. The pump on the front looks like it leaks with all the buildup on it. It may be a problem to rebuild?? The tank has the cap you mentioned.

First a disclaimer, I can't recall ever working on one of these tractors, but I have worked on a bunch of later ones.
When I go out on a motor making od noises call I take a oil filter with me.
I pull the filter to check for junk So I would suggest you pull your filter and check for sludge.
Every old Cat motor I have seen has a plate on the side or bottom to access the oil pump.
Pull that plate and you can check and clean the pan.
Good luck
Bob

Thanks for that advice Bob! Once I'm at the point of working on the machine, I'm going to definitely need manuals. I will need to become a member here. I probably should start reading up on them now.
One thing about older machinery, and engines, the idea, and tech was lacking in the filtering, of fuel, hydraulics, oil, and air. I have an 50's AJS scrambler that was built for desert racing, and it came stock from the factory without an air filter on the carb! No warranty...no filters needed!

I hope my engine has a somewhat tighter clearance, but the pony motor end play on the flywheel is considerable. I don't know how much is too much there.