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New to me 1936 Caterpillar RD4, get it running project

mla2ofus

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I'm not positive but I think the movable part of the pulley just threads on the fan hub and moves in and out to change the pulley pitch diameter. Can't you just loosen the radiator mount bolts enough to tip it ahead and gain enough clearance for the belt. Just start at the top fan blade and rotate to thread the belt over the next blade and so on.
That large hex nut on the water pump shaft compresses some graphite impregnated packing and it is the shaft seal. Can't tell for sure but it looks like it may be about out threads. If that's the case it will soon start leaking coolant around it. There's a special wrench made for that so look for a pic of it. It might be possible to sacrifice a 12 point box end wrench by cutting just enough to slip over the shaft. It doesn't have to be super tight, just enough so it weeps a drop or 2 a minute as the coolant is the lube for the packing. Once you get the wrench made just try to tighten it a little bit. If it will you may be OK. If you can't tighten it all then it's new packing time and I'll recommend removing the water pump which might force you to remove the radiator anyway. I hope I'm not discouraging you, just trying to make sure you only have to do this once. One caution if you have to change the packing. The packing is one piece with a split in it to slip over the shaft. Of course you have to dig out the old which can be a real biotch!! I hope you can find a video of this being done. Probably better than all my typing!! Once installed run the nut down 'til it's just past finger tight fill with coolant, start the main engine and watch how much leaks past the packing and gently tighten the nut until it leaks a little bit.
 
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m1west

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I'm not positive but I think the movable part of the pulley just threads on the fan hub and moves in and out to change the pulley pitch diameter. Can't you just loosen the radiator mount bolts enough to tip it ahead and gain enough clearance for the belt. Just start at the top fan blade and rotate to thread the belt over the next blade and so on.
That large hex nut on the water pump shaft compresses some graphite impregnated packing and it is the shaft seal. Can't tell for sure but it looks like it may be about out threads. If that's the case it will soon start leaking coolant around it. There's a special wrench made for that so look for a pic of it. It might be possible to sacrifice a 12 point box end wrench by cutting just enough to slip over the shaft. It doesn't have to be super tight, just enough so it weeps a drop or 2 a minute as the coolant is the lube for the packing. Once you get the wrench made just try to tighten it a little bit. If it will you may be OK. If you can't tighten it all then it's new packing time and I'll recommend removing the water pump which might force you to remove the radiator anyway. I hope I'm not discouraging you, just trying to make sure you only have to do this once. One caution if you have to change the packing. The packing is one piece with a split in it to slip over the shaft. Of course you have to dig out the old which can be a real biotch!! I hope you can find a video of this being done. Probably better than all my typing!! Once installed run the nut down 'til it's just past finger tight fill with coolant, start the main engine and watch how much leaks past the packing and gently tighten the nut until it leaks a little bit.
This is good stuff, likely not going to know by reading the manual. Keep it coming
 

mla2ofus

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M1, I'm just passing along what I was taught by old timers and the school of hard knocks. https://www.acmoc.org/s check out this site 'cause they collect and restore old Cat eqpt. of all sorts. Maybe join them and you might get more informative info than I'm able to give. The pic of the water pump jogged my memory on the water pump packing nut so keep the pics coming. Those pics help pull old memories out of the cobwebs in my brain. I haven't been around any cats for 20 yrs and it's been 40 yrs since I worked on the old cats.
 

mla2ofus

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When you get around to it pull up the floor plates and post a pic of the clutch/flywheel. I may have comment to make on that. Which reminds me: if you plan to get off the cat and leave it running make a habit of putting it in neutral and engage the clutch. This will save wear on the pilot brg. When ready to put it back in gear do so only from idle to reduce grinding gears. The kindest thing Cat ever did for stick trannies was the decelerator pedal which with a push of your right foot would bring the engine down to idle and upon release of it would bring the engine back to preset speed. Again a little tidbit from the old timers!!
 
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m1west

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Today got the cover and lower radiator pipe off.
while under there I chipped all the crap from around the oil pan inspection cover.
noticed the old gal has had its radiator housing and oil pan repaired with gorilla welding in the passed. You would think this thing would have come with a skid plate to prevent such things. It will have one before it gores to the mountain, there are rocks everywhere.
In the end the radiator is going to be supported from overhead and loosened or removed to give clearance to remove the water pump assembly, as its on studs and there is no room.
While playing with the adjustable fan pulley I noticed the fan has play on the shaft. I watched a video and there are an inner and outer bearing that will need to be replaced, so might as well remove it and service the whole pump. Its hard to remove so now is the time.
today o filled the pony gas tank with acetone to remove the varnish and noticed a pin holier the weld on top the tank. its not a rust hole, must have been there since the beginning. tomorrow I will dump the acetone and add molasses and water to de rust then repair the pin hole.
 

m1west

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M1, I'm just passing along what I was taught by old timers and the school of hard knocks. https://www.acmoc.org/s check out this site 'cause they collect and restore old Cat eqpt. of all sorts. Maybe join them and you might get more informative info than I'm able to give. The pic of the water pump jogged my memory on the water pump packing nut so keep the pics coming. Those pics help pull old memories out of the cobwebs in my brain. I haven't been around any cats for 20 yrs and it's been 40 yrs since I worked on the old cats.
I have been on there web site as a lurker, there is a lot of info there also. I watched a video on the injectors and thats something you don't want to go bad, there are no replacements except for used you may or may not find. A guy had a test stand made up to test when they crack ( 1500#) and to see the spray pattern. It looked like he used a brake cylinder with a resivour and gauge to make the pressure required. In the video he stated that as far as he knows there are no services to get them rebuilt at this time.
 

m1west

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The turning brake handles move but are stiff, what is the procedure to remedy that.
 

mla2ofus

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IIRC they are just naturally hard to pull. I doubt they have hydraulic boosters like the later cats have. Oil all the linkages on them and that should help some. As for the injectors I advise to just leave them alone and make sure those injector lines and all connections are operating room clean. A microscopic speck can create injector problems. just remember the fuel going thru them has already been thru the fuel filters.
The clutch should have some definite resistance as it toggles in. If not adjust as needed. Try to avoid slipping the clutch. Slipping it at idle Is OK but not for over a few seconds. DO NOT slip it at full throttle, it's designed to be either in or out. You'll be surprised at what you can do with the clutch fully engaged in first gear at idle.
the 5th pic jogged my memory about the track rollers. They should have a pipe plug or a large "button head" grease fitting on the outer end and it wouldn't hurt to pump a little grease in them. Once you have it running and ready to work have someone move it in 1st ge3ar at idle and observe all the rollers to insure they are turning. If you have a laser thermometer and you've given it a good workout you can use it to compare temps on all the rollers. A cat mechanic told me yrs ago if you run a cat long distances on even hard dirt roads you're leaving a trail of dollar bills.
 
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m1west

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IIRC they are just naturally hard to pull. I doubt they have hydraulic boosters like the later cats have. Oil all the linkages on them and that should help some. As for the injectors I advise to just leave them alone and make sure those injector lines and all connections are operating room clean. A microscopic speck can create injector problems. just remember the fuel going thru them has already been thru the fuel filters.
The clutch should have some definite resistance as it toggles in. If not adjust as needed. Try to avoid slipping the clutch. Slipping it at idle Is OK but not for over a few seconds. DO NOT slip it at full throttle, it's designed to be either in or out. You'll be surprised at what you can do with the clutch fully engaged in first gear at idle.
the 5th pic jogged my memory about the track rollers. They should have a pipe plug or a large "button head" grease fitting on the outer end and it wouldn't hurt to pump a little grease in them. Once you have it running and ready to work have someone move it in 1st ge3ar at idle and observe all the rollers to insure they are turning. If you have a laser thermometer and you've given it a good workout you can use it to compare temps on all the rollers. A cat mechanic told me yrs ago if you run a cat long distances on even hard dirt roads you're leaving a trail of dollar bills.
Keep the experience coming, its priceless
 

m1west

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Didn't get much done on it today, I did get the last bolt out of the water pump by working it back and forth for awhile as I didn't want to shear it off or pull the threads out with it. I was able to loosen the bolts that hold the radiator, also watched the water pump rebuild video again and got the part numbers. Tomorrow I am busy in the morning so back on it Saturday.
 

mla2ofus

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Don't let it wear you down. If you hurry you're apt to make mistakes. That ol' girl has been waiting for you for a long time, a little longer won't matter. Don't forget the antiseize on every bolt and nut!!
 

m1west

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Today I had a few minutes this morning so I pulled the flywheel, throwout cover off. Looks good in there no water. There is a oil cup on tp so I filled it up. Also had time to get the radiator rigged up with a come a long so I can pull it and the water pump.
Is there a question about the throwout bearing?
no, just jogging your memory.
 

m1west

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Yesterday the operation and maintenance manual showed up. I went out last night after it cooled down and added oil to the oil cups for the turning brakes, first penetrating oil and worked the levers, then WD40 and worked the levers then gear oil and worked the levers. I checked them a little while ago and the have freed up a lot. They even have a spring return when you pull back on them then release. I started too late ordering Magneto parts as they seem to all be back east and didn't answer, so that will be next week. Plans changed and likely will be heading to the cabin tomorrow, my cabin neighbor called and the fire up there is gaining ground and could become a problem.
 

mla2ofus

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Well, the manual should cover clutch adjustment if needed. If your not sure post a pic of the clutch. Once you get it running you can figure out if steering brake adjustment is needed. Glad your steering clutches freed up. If the inside of the mag cap looks as good as the mag I'll bet she'll start right up with the old stuff.
Steering brakes remind me of a funny story that happened with a D-6 that belonged to a farmer I worked for. It seems a family member was trying to plow snow with it and finally told the farmer he'd been standing on the brakes and couldn't make it turn. Greg asked if he'd tried using the steering clutches. With a blank look he asked "What's that". Later we tried to tighten the bakes and there was no adjustment left. When we changed the brakes they were worn down metal to metal.
 
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m1west

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The last hurdle will be checking out the bottom end of the main engine, if thats good we are in fat city.
 

FrancSevin

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Gentlemen, this project has been a joy to watch and read. Very entertaining.
Better than Bob Villa in This Ole house!!!!!

My impressive mechanical feat today was resetting the front wheels on an old Sears lawn mover. No comparison.
I am in awe.
Please continue.
Thanks
 

mla2ofus

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Thanks, franc, I'm just trying to pass on info I was taught by old timers long ago to the next generation. m1 has a learning curve on operation of this ol' girl. Like I told him getting that cable winch clutch and brake set just so can take a lot of frustration out of dozer operation.
 

m1west

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This morning I removed the radiator and water pump ( getting the pump off was challenge as it registers in the block, and hasn't been off there since who knows when.
Next I broke the pump puley and fan assembly down to replace the bearings and seal.
I left the impeller end alone, the carbon seal wasn't leaking, with adjustment left on the nut and there is no play in the bushing.
I already have the part numbers for the bearings and seal, they are common items.
I really like the adjustable pulley to tension the belt, they could have used some idler assembly like they do now adding complexity and more maintenance.
After I posted yesterday the magneto parts guy called me back and I got new wires and spark plugs coming.
As seen in the video the turning brake handles have freed up nicely.
 

m1west

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Gentlemen, this project has been a joy to watch and read. Very entertaining.
Better than Bob Villa in This Ole house!!!!!

My impressive mechanical feat today was resetting the front wheels on an old Sears lawn mover. No comparison.
I am in awe.
Please continue.
Thanks
Hi Franc, thanks for the words, this is how we get the equipment needed without spending $200,000.00 on one. Every year I cut my acreage down with a 1953 ford jubilee tractor, I sits on average 11 months out of the year. Every year for the passed 14 years it starts right up and does the job without complaint. Its not fancy, no power steering or computers. When the Dozer goes to the mountain that will be expected of it also. The machines are built dirt simple and robust with internal gears, not belts and pulleys and no electrical or eltronic crap to go wrong. These old machines if operating properly will do the job as well as the new one, you just have to understand how they operate and will still be doing it somewhere when the new computerized under built mostly plastic one comes apart. Yep I'm out in the elements with no A/C but I don't have a $5,000.00 payment to make on it each month either. As far as fixing them up, thats not rocket science either, there are still a few around like Ol stonebreaker to help you out with there experience. I would think the biggest hurdle is having a place to work on it with the time and determination to finish it. Most of the projects I have done, started with someone else that did the bulk of the work then lost interest.
 

m1west

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Another thing that happens to me for what ever reason, when I start looking for a project, what ever it is, its always a long process locating what I am looking for. As soon as I buy one I start seeing them everywhere. Sitting in fields, behind business you name it.
 

FrancSevin

Proudly Deplorable
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Hi Franc, thanks for the words, this is how we get the equipment needed without spending $200,000.00 on one. Every year I cut my acreage down with a 1953 ford jubilee tractor, I sits on average 11 months out of the year. Every year for the passed 14 years it starts right up and does the job without complaint. Its not fancy, no power steering or computers. When the Dozer goes to the mountain that will be expected of it also. The machines are built dirt simple and robust with internal gears, not belts and pulleys and no electrical or eltronic crap to go wrong. These old machines if operating properly will do the job as well as the new one, you just have to understand how they operate and will still be doing it somewhere when the new computerized under built mostly plastic one comes apart. Yep I'm out in the elements with no A/C but I don't have a $5,000.00 payment to make on it each month either. As far as fixing them up, thats not rocket science either, there are still a few around like Ol stonebreaker to help you out with there experience. I would think the biggest hurdle is having a place to work on it with the time and determination to finish it. Most of the projects I have done, started with someone else that did the bulk of the work then lost interest.
I own an 8N ford tractor with a brush hog. I owned a'51 8n with a back blade and a bucket. Beautiful machine I rebuilt. It was stolen off my son's place whilst I had it in Connecticut doing some work on his land. Before that I had a 9n (1939) with a blade and front bucket owned by the subdivision. All were excellent tools for doing the job. The9n sits on my property rusting because the HOA will not sell it to me.

But that is another story

Currently I own a case 360 dozer with a compound bucket /blade and a 1973 JD310 diesel with a backhoe and bucket.

Looking forward to moving dirt and rock with both on my Ozark mountain property this fall.

So yeah, I get what you are sayin.
 

mla2ofus

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You're coming along nicely, m1, I see we found a zerk on the fan hub. Be interesting to see what the manual says for frequency of greasing it. It's too bad the old ones don't have a reversible fan like the younger ones did. You could reverse it in just a few minutes and it was so nice to have all that hot air blowing out the front in the summer and with curtains on each side of the hood kept you nice and warm in the winter so long as the cat was worked hard enough. If you have to work it much in the winter get some canvas and eyelet install tool and make some curtains for it. If it has a temp gauge just cover part or all of the grill to get more heat out of it. Won't hurt the engine to have a little extra heat in it so long as it isn't getting up close to the red zone. I see one gauge behind the right steering clutch handle. Temp or oil pressure?
When you get her in the dirt/rock feel free to ask questions regarding techniques in use of the dozer.
 
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