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New to me 1936 Caterpillar RD4, get it running project

m1west

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They look as good as factory made.
A trick my Dad showed me when I was a kid. Lay the gasket material over the part, then lightly tap the gasket material at the edges of the voids and holes. Marks everything perfectly.
 

m1west

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Today I made the rest of the gaskets needed to put the water pump, radiator and water pipes back together, then cleaned all the mating surfaces. Also chased all the threads.
Tomorrow I will stretch a hose over there and clean the radiator in and out. Also take a small screw driver and needle nose pliers and straighten all the cooling fins on the radiator the best I can.
 

m1west

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Today, I drug the hose down and thoroughly cleaned the radiator inside and out, Lots of mud and crap. Then I took a small screw driver and needle nose pliers to straighten the cooling fins so air could circulate again. About 20% of the cooling fins were bent over, likely from fan belt changes. Not perfect but didn't want to break the fins loose from the water tubes. Now its ready to put the water pump, belt, pipes and radiator back together again.
 

NorthernRedneck

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Nice progress. Good to see an old dozer coming back to life. I have a lead on an antique cat d7d made in 1959. Looks like it was abandoned in early 80s judging by the tree growth in the area where they were logging. It's sitting about 5 miles from my camp down an old logging road that was previously gated off due to an old landfill site that closed at the beginning of the road. There's also an old slasher nearby sitting abandoned.


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m1west

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Nice progress. Good to see an old dozer coming back to life. I have a lead on an antique cat d7d made in 1959. Looks like it was abandoned in early 80s judging by the tree growth in the area where they were logging. It's sitting about 5 miles from my camp down an old logging road that was previously gated off due to an old landfill site that closed at the beginning of the road. There's also an old slasher nearby sitting abandoned.

Depending nohow well it is sealed up to water, you could get it going
View attachment 139421
 

m1west

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I liked the idea of hanging an extra belt in there but couldn't easily come up with one and they are pretty beefy without much load, so I went ahead and put it all back together. I need to either buy or make a jam bolt that locks the adjustable pulley, it has the threads turned off the last 1/4" and fits into a slot that keeps the bully from turning. That task is checked off now.
 

m1west

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Lookin' good!!
Here is one for your memory bank, the radiator cap is missing. I will take a picture of the opening. It doesn't twist on, it bolts on with a center stud that sticks up and it looks like it seals on a flange. What confuses me is there is a overflow tube that is lower in the radiator neck than the sealing surface. The only way for that to work is if its not a pressurized system? You recall anything about that?
 

mla2ofus

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Never gave much thought to it so let's assume it isn't pressurized. That cap is probably meant to keep coolant from leaking out when descending steep hills. Find a pic of one and with your machining skills I'm sure you can make one. You probably don't want to top it off completely else you'll just lose some coolant thru the overflow tube. As long as the coolant is a couple of inches above the tubes cold it will be OK. See if the manual mentions anything about being sure all air is bled out of both engines and how to do it.
 

mla2ofus

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You probably already have figured this but I thought I should mention that cap had a rubber seal washer also.
 

m1west

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Pony magneto wires and spark plugs showed up today. Tomorrow I will put the mag and carburetor back on. After that its change oil in the pony, main and finals. Then its time to light her up.
 

mla2ofus

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Wish I was closer as I have an old pair of crimping pliers with a section of the jaw for crimping those type of connectors. I'm anxious to hear how the startup goes!!
 

m1west

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Wish I was closer as I have an old pair of crimping pliers with a section of the jaw for crimping those type of connectors. I'm anxious to hear how the startup goes!!
Start up is likely still a week or 2 away, still have to paint the pony gas tank after its de rusting and inspect the bottom of the main then oil everything. Got COVID so I'm moving a little slower.
 
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