New to me 1936 Caterpillar RD4, get it running project

m1west

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Hi all, I got the machine home yesterday. First thing the hornets and wasps came out of everywhere as soon as it hit the ground. I sprayed it with wasp spray and killed the ones flying around, next I went to the hardware and bought a roll of plastic and a 6 pack of foggers. I put all of them under it this morning and left it tented for 3 hours. So far so good. Next I familiarized myselfIMG_2482.jpg with it verifying everything still moves. The first task is to get the pony motor going which at first glance is going involve the fuel tank cleaning, carburetor clean or rebuild and the magneto doesn't spark, it turns over and has compression. Next I engaged the pony to the main Diesel engine and turned it over with the pony motor starter wheel. The fuel tank is at least 1/2 full of diesel and had the fuel valve left on. I cracked the line at the lift pump and good fuel came out with no water. The oil in the main engine is over full and I am assuming that is where the other half of the fuel is. Thats OK though because thats likely what kept it from locking up from setting. I started taking the cowling off to expose the pony motor, then it got too hot to work in the sun. Tomorrow morning I would like to get the pony motor exposed and get the gas tank, magneto and carburetor off so I can start working on them. After that I will go after draining the main engine and clean the oil pick up screen in the bottom of the oil pan. Also remove the radiator clean it and inspect it. The cap is missing and its full of crap, plus the reason given for parking it was the fan belt broke and there is not enough room between the radiator and fan to get it in. Those tasks won't take long and I will likely still be waiting on parts to get the pony motor going. I will post pictures as I go.
 
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300 H and H

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It may well be your dip stick is marked for checking while running.
I have a gen set with a D4400 engine on it. That is how the stick is marked, you check it running.
good luck I will be watching this thread.
 

m1west

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It may well be your dip stick is marked for checking while running.
I have a gen set with a D4400 engine on it. That is how the stick is marked, you check it running.
good luck I will be watching this thread.
thanks, I will need help
 

m1west

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Ended up having to work today and didn't do anything on the cat, but I will hit it in the morning.
 

m1west

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Here is a couple pictures of it without the plastic on it. The bottom one shows the missing fan belt.
1- there is no room between the radiator and fan to get the new one in. I am planning to pull the radiator to clean it and inspect so thats not an issue right now, but would like to know the easy way if there is one for future.

2- there is no visible way to get the belt over the pulleys and tension it. How do you do that?
 

mla2ofus

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Are you saying there's not enough clearance between the blades and the shroud or the blades and the the radiator core. I'll bet the outer half of the fan pulley is adjustable pitch :ie it screws in or out to change the pitch diameter of the pulley to tension the belt. If so take it apart while the radiator is off and put antiseize on the threads to make future adjustment easier.
Never seen tilt adjusters like that on a dozer. They are used to tilt the dozer left or right or by adjusting both in the same direction change the angle of attack of the dozer ie: if you want it dig more tilt it forward, if you want to just smooth ground tilt it back. If the clutch and brake in the cable unit are in good shape it will be tricky to get it set so the dozer will drop about one inch if you just tap the control handle a little. DO NOT let any oil or grease get into the clutch and brake in the unit or it will make your life as an operator difficult!! Grease what needs it sparingly. From the looks of the cable take it all off after taking a pic of how the cables are reeved thru the front pulley blocks, coil it in a 5 gal bucket and soak overnite in 80w90 oil, then wrap some tie wire around the coils and hang it in the sun to drip out all the excess. If for some reason you need to cut the cable, seize it with a few wraps of tie wire on the side you want to save and cut it with a cutoff disc on a grinder. With all those pulleys the cable will last longer with lube in the wires. And don't be afraid of overgreasing the pulleys, the cable will like it!! I've spent many hours on the D-8 14A series which was about the same just bigger. Most of the old guys that knew how to adjust the cable unit are dead.
Doubt you'll ever need to raise the dozer that high but be careful not to "2 block" it :ie run the dozer pulley up to the anchor pulley or you're apt to break the cable.
HTH
 

m1west

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Thanks, when I get the radiator off , I will check out the pully to see if it adjusts like you said to get the belt on, Thats a good suggestion on the blade lifting cable, to save it. I imagine I should get it running so I can use the winch to unwind it off the drum and wind it back on. I think I have the starting procedure down after a session of youtube on that subject. I have faint memories of riding around on one similar with my dad when I was about 4 years old and him getting off to do things with me pulling handles when he told me to. The plan is when I get it running and serviced, is to play with it here a little then take it to the mountain where I really need one right now. Another way to terminate a cable shown to me on a job by an old operator by using a torch to melt it off and it welds all the strands together so it can never Frey. Keep the experience coming my way its appreciated and priceless. I have a manual coming and tha should be some help also.
 

mla2ofus

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I mentioned the tie wire and cutoff disc not knowing if you have a torch. I'm sure it was mentioned in video of starting it but pull the clutch handle back away from engagement to use the clutch brake to stop the pinion gear from spinning for engagement with the flywheel.
Since the dozer lowers by gravity just tie off the control handle in the down position. That releases the brake and it should pull off by hand w/o the engine running. Once you get it running practice lowering the dozer by small increments. If you just drop it to the ground no matter how fast your reaction time you'll get the cable on the drum all wrapped over itself which contributes to excess cable wear(another reason for cable lube). A cable dozer has a learning curve to it. It might have the winch powered thru the tranny which means if you stop you cant lift the dozer w/o the tranny in neutral and the clutch engaged. Speaking of the clutch, if you get off and leave it running for very long. The main clutch should also have a brake by pushing forward on the clutch handle to stop the tranny gears. Put it in neutral and engage the clutch to save pilot brg wear. If you're trying to dig wet, sticky clay or frozen ground and the dozer pulls itself down don't try to pull it up before stopping forward motion or you'll be looking for some new cable.
If you work it in snow you'll need to cut 1 1/2"-2" holes on each track pad to give a place for sprocket teeth to push the snow out or you'll have severe undercarriage damage.
OK, I'll shut up for now and just wait for questions and hope I have correct answers.
 

m1west

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Keep the info coming. Today I took the air pre filter, exhaust and hood off so I have complete access to the pony and main engine, then took a leaf blower and got rid of all the crap stuck in everything. also got the gas tank off, Magneto and carburetor ready to pull from the pony motor. There were hornet/wasp nests in everything. ( the tent and foggers completely killed every one )The air pre filter was packed as well as the 5 gallon bucket covering the exhaust, none of it made it into the manifolds or the oil bath filter. I like the radiator design ( no hoses ) but that puppy looks heavy, likely have to rig it off with the tractor bucket and a coma long. Where is the best place to separate it from the engine? lots of choices where it comes apart. Also you were 100% correct on the adjustable pulley to get the belt on and tension it. Tomorrow I will remove the carburetor and magneto from the pony motor, then start pulling the radiator.
 

m1west

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After couple more youtube videos and looking at it, I figured out how to remove the radiator. Basically the radiator hoses are flanged cast iron pipes that un bolt. then there are large mounts on the bottom of the housing to the front of the engine and it will come off with the help the tractor and a com a long, in videos they were saying it weighs around 400#.Plan is to clean it and the water passages in the block and water pump. Then look at the bottom end of the main engine. If everything looks good, clean the pan and put everything back together then put the cleaned radiator back on with the new belt installed. Take a peek at the injection pump and injectors. if that checked out I will be running right after getting the pony motor going. So far what the seller told me is true. I also learned there is an oil cooler in front of the radiator that has been abandon, it is a common modification as it was found to be un necessary after better oils were formulated.
 
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mla2ofus

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I don't know anything about the radiator connections. Whether they use O-rings or gaskets, if gaskets you'll probably have to make your own with some heavy gasket paper and silicone. I think I'd get the lift cable out of the way for radiator R&R.
From what I see in the pics the track sprockets look very worn which might explain why the tracks look so tight. If this is true keep it out of the mud and snow.
IIRC the housing on the right side of the injector pump is where the fuel filters are. They are little fibrous cylinders about 1 1/2" in dia and 6"-8" long. I wouldn't bother them unless it acts like it's starving for fuel. Might as well remove the air cleaner oil reservoir and see what it looks like.
 
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m1west

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In the videos I watched I think the radiator pipes have gaskets.The track sprockets are actually in great shape, I think what you are looking at is where the edge of the paint, where it has warn off the sprocket teeth. I will post a close up. Yep planned to look in the oil bath housing, from what I can see its still full of oil. Also need to change the oil filter when I drain it and refill. Keep the comments coming.
 

mla2ofus

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Yeah, those sprockets have some miles left. I just couldn't see them well enough even expanding the first pics.
 
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