Just bought another machine for the farm. Sat for 4 years, fired up right away, seems to track properly, just needs some maintenance and adjustment. As a machine formerly owned by the Army Corp of Engineers, I hope to find the time to restore it to OD green paint. First question - I am looking at manuals for the 44A series and they seem to be tractor only. How do I figure out what manual is needed for the blade and winch equipment? Second question - Why was this machine equipped with a cable blade in 1963? Did the army prefer simplicity over hydraulics? One less fluid to deal with? This will be the first cable dozer I've owned and operated. Pretty exciting!
Cat didn't produce the dozer for their machines at the time these tractors were built, I was told there was a tag on the back of the blade they needed to get parts for the dozer. Mine is missing that tag and I had a heck of a time getting the correct wear bars/corner bits for it. Balderson was one of their suppliers but no way to know without the tag# or some of their blades had a plate in the top of the blade with their name one it.
Cat started building their own blades in the early fifties . My Cat 1950 5u had a cat 2s blade, that D6B has a Cat Blade, we had one just like it. If the tag is missing, the serial # is stamped on the right hand corner on the back of the blade near the top.There should be 2 rivet holes between these holes should be a serial#, it takes a little detective work to find it
Actually, you are both right, by that age, some were Cat, some were made by others. Even the Cats weren't considered part of the tractor, they were attachments. That's why the tractor weights didn't include the blade or arms.
It was a option, especially if Scraper work was required , A cable control blade set up properly will give you more feedback than a hydraulic one, it’s fast, raises the blade higher. I learned on a 19A D9 with a cable blade in a gravel pit, talk about a wavy roller coaster ride, the other operators gave me a hard time as I was only 20 at time. Also had a D7E with a cable blade, loved that machine. It’s all how the control is set up. Main thing is keep the slack out the cable, it’s a bit of a learning curve enjoy
My Cat area rep. came and looked at my blade and couldn't find a tag or stamped number nor tell me what blade it was, not tell me who built the dozer so I didn't feel bad....it took three different orders to get the correct edges....finally measuring the bolt pattern/spacing and taking and sending pictures they did finally match up the correct edges/end bits for my blade....without that# it's a total shot in the dark.
My bad, I was lead to believe different...I stand corrected.
From what I can make out in the pictures that's a Cat 16Cxxxx series angle blade and Cat #25 CCU.
I got it home! Ordered manuals and filters to start changing fluids. It is a 16C1 blade (6A?) and a 32E2 cable control (126). The engine serial number matches the tractor and the hour meter on the injection pump shows 1,453 hours. One item that needs addressed is a missing bearing cap from the rear of the right track roller frame. You can see in the attached photos the bolts broke and the cap and bearing liner disappeared. I will be posting some ads looking for used parts but I can get these parts from Cat, they're just spendy. The cap is PN 7B5977 (7B5978 plus dowel 9P7751). It's shown in the upper left corner area of the parts diagram below.
Oh my yes get that cap !!! All the side load to the track frame is now just on the dead axle !!
What part is the dead axle you refer to? I figured that cap was important. Who knows how long its been missing. The left side is still there but loose. Let the cheap dozer start getting not so cheap!
That shaft that the cap goes on is the dead axle.
The operator and maintenance manual for your tractor is readily available, it is a Dept of the Army Technical Manual, TM-5-2410-229-12. However, the Dept of the Army Service Manual for your D6B seems to be quite elusive. There used to be a big list of TM's available online, but it seems to have disappeared. The following site may be able to assist in your search for any Dept of the Army Service Manual - but it's entirely possible that the military merely used the regular, civilian Caterpillar Service Manual. https://guides.loc.gov/us-army-technical-manuals/obtaining-copies Caterpillar commenced production of their own design angle blades and straight blades in 1947, but other brands/makes of blades were always available as an owner choice by tractor buyers. Cable controls were chosen as the preferred method of implement control during the early stages of WW2, and this preference was driven by the insistence of Robert G LeTourneau, that cable controls were superior in every way to hydraulic controls. Of course, in 1942, R.G. Le Tourneau was right - because the hydraulic systems of that era were low pressure, slow, and seals were manufactured from organic materials such as leather. However, major technical and product developments during WW2 saw the introduction of nylon, teflon and other synthetic materials that could resist high pressures, high temperatures, and provide long-wearing characteristics, saw hydraulic and attachment manufacturers move rapidly into introducing higher operating pressures and high quality seals, which allowed for faster hydraulic speeds and performance, that gradually drove cable control systems out of business by the late 1950's. However, old habits die hard and the military obviously still thought in the 1950's, that cable controls were superior. The fact that minimal amounts of oil were needed for cable control was advantageous in some respects, and it removed the problem of ensuring the correct oil was in the right location, and that operators couldn't become confused over oil types to use.
I have seen D8K machines with cable blades so apparently Cat didn't give up on cable till 1980. You seem to be the only one confused on oil types. Bad Bob
Found the TM: https://www.google.com/books/editio...ational_Maintenance/4Pchm4l9u5IC?hl=en&gbpv=0 Also found this interesting FM on air dropping this dozer and other machinery: https://www.google.com/books/edition/Airdrop_of_Supplies_and_Equipment/iRIEI1oxp7wC?hl=en&gbpv=0
When you go to replace that missing diagonal brace cap, check that there's a steel bearing insert still in the arm of the brace. There are two steel bearing inserts inside the cap and brace, just like a big end bearing, and they're dowelled to stop them from turning. It looks to me like the bearing insert in the arm of the brace is missing, so you'll need to order two bearing inserts, as well as the bearing cap. The parts book for your 6A blade is Form 33684, and there are copies available on eBay. https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2499334.m570.l1313&_nkw=33684&_sacat=257888 Here is the Service Manual for your #126 cable control unit. https://www.ebay.com/itm/334343748893 And finally, the Operation and Maintenance Manual for your Model 126 cable control unit. https://www.ebay.com/itm/114190690094
Are the bolts that held that missing cap broken off? if that isn't just dirt jammed in the holes I say the first thing you'll want to do is get those removed, then order the parts...the list may be longer before you get them removed. If the other side is loose now you'll likely need new parts there too. Oh, and there's no such thing as a 'cheap dozer'
I can pretty much say with certainty your D6 hasn't been air-dropped! Your tractor doesn't have the 'chute support brackets that are welded to the outside of the track frame. Quite a number of air-dropped items of equipment didn't make it! - and quite a number have suffered damage in hard landings. However, I must say I'm surprised it doesn't have additional tiedown lugs welded on the track frame. This is pretty much standard design for military tractors - the military like them properly secured! I would also have to offer the opinion that the canopy is not military, and has been added later. The reason being, no photo of any military D6 of this era shows any canopy - and the tractor information tag says the tractor is 6' 4" high, which rules out any canopy. I hate to think what it does to your aircraft handling, when a sizeable bulldozer falls out the back of your 'plane!! https://www.constructionjunkie.com/...-airplane-is-the-coolest-way-to-site-mobilize
A 44A is not a military tractor. It has a Corps tag which means they bought it and the Army corps is not a branch of the .Military . A parts book for a 57A or a 37H D6 will work for that tractor. Bad Bob
Interesting concept, having an Army that is not Military - yet the USACE also encompasses Combat Engineers, who definitely are Military. In my neck of the woods, Army is Military, period. You wear a uniform, swear allegiance, and are subject to Military Law and rank and promotion systems. How does that work in the section of USACE that is tasked with civilian construction work? Do they simply work on a civilian system? Are they still subject to military law? I did note, after more reading, that the Military TM-5-2410-229-12 is for the 37A D6B, the narrow gauge version. Does this mean that Leadfarmer is wasting his time painting his tractor OD, or trying to find OD paint under that Cat yellow? - because it never was a Military tractor?
This dozer was meant to be air dropped in Vietnam jungle and operator would be parachuted in this was in 1967.
Strangely enough, the D6B's were never airdropped in one piece in 'Nam. They were brought in by pieces via air, and reassembled - and when they were required to be moved again, they were lifted and moved around in two sections by CH-54's. The book below gives the details. https://history.army.mil/html/books/091/91-14-1/CMH_Pub_91-14.pdf
They were d4 with d6 engines cable blades in 67 I was in 47th airborne engineers.
Thanks for your service and important work in 'Nam. I served as an NCO with 17th Construction Sqdn, RAE. We ran teams of D8H's on jungle clearing, operated Cat 12E's, Euclid S7E scrapers, Cat 966B's and 996C's, plus a wide range of ancillary construction equipment, including on-road and off-road dump trucks. We also reconstructed roads in SVN, constructed water points and operated them, did civil works for the South Vietnamese people, built accommodation for Australian and South Vietnamese troops, set up and ran a concrete plant, and constructed bridges. We also had our fair share of enemy "contacts", and a fair number of equipment and personnel losses to mines and booby traps. The book I linked to above, specifically states their battalion tractors were D6B's. 9 mentions of D6B, on pages 63, 179, 319, 325, 326 & 326. Your 47th Airborne Engineers gets no mention in the book above, nor in the one below - "Vietnam Studies - U.S. Army Engineers - 1965-1970". Was your unit part of the USACE, or part of the USAF? I'm still puzzled over the activities of the Army Engineers and the USACE in SVN. In SVN, we had a good relationship with the USACE guys, and they lent us equipment such as D7E's and TD-15's. However, these U.S. Engineers we interacted with, were all military. They wore military uniforms, carried weapons, held rank, and operated as fighting units. Yet there appears to be U.S. Army Engineer units sent to SVN that were not combat units. I don't recall any non-combat Engineers in SVN, but they may have been there, and we just didn't interact with them. There were civilian U.S. contractors in SVN, such as RMK, who carried out major construction projects for the U.S. Govt. But these guys were strictly civilian operators. https://history.army.mil/html/books/090/90-22/CMH_Pub_90-22.pdf
The United States Army Corps of Engineers ( USACE ) is an engineer formation of the United States Army that has three primary mission areas: Engineer Regiment , military construction , and civil works . The day-to-day activities of the three mission areas are administered by a lieutenant general known as the commanding general / chief of engineers . The chief of engineers commands the Engineer Regiment, comprising combat engineer , rescue, construction, dive, and other specialty units, and answers directly to the Chief of Staff of the Army . Combat engineers, sometimes called sappers , form an integral part of the Army's combined arms team and are found in all Army service components: Regular Army, National Guard , and Army Reserve . Their duties are to breach obstacles; construct fighting positions, fixed/floating bridges, and obstacles and defensive positions; place and detonate explosives; conduct route clearance operations; emplace and detect landmines; and fight as provisional infantry when required. For the military construction mission, the commanding general is directed and supervised by the Assistant Secretary of the Army for installations, environment, and energy, whom the President appoints and the Senate confirms. Military construction relates to construction on military bases and worldwide installations. It looks like they're Army in this article...however, it doesn't say what tags they require on the dozers they employ.
Mcrafty1, the link below tells me more about what I wanted to know - that out of 37,000 USACE personnel, only 650 are Military, the other 36,350 are civilians. https://www.360training.com/blog/usace-army-engineers-corps I'm still trying to grasp how 650 Military personnel have command over 36,350 civilians. It doesn't work like that down under here - military are military, civilian is civilian, and the only time the military can dictate to civilians is when they have been specifically tasked by the Govt., to control the civilian population, as in natural disasters or emergencies (or pandemics). Soldiers were called in to man checkpoints when borders and regions were locked down here in 2020 - but otherwise, civilians are free here to do what they choose (within the law). If you work for USACE as a civilian, is it just like working for any other corporate operator? - and you can tell them to shove their job, anytime you feel disenchanted? You can't tell your CO that when you wear the green - you can be charged with disobedience of orders, "conduct to the prejudice" (of good military order and discipline), or a raft of other military charges.
Good observation, I don't know how that all shakes out, I always thought the Army Corp of Engineers were...well, Army. But then again I'm just a student working my way through life and have never forgot the fact that I'm never going to be too old to learn.
The USACE in the US is most visible in waterway work. They manage river systems and levee systems, famously in New Orleans. Possibly other port work? they also overlap somewhat with Interior, Reclamation, Fish and Wildlife etc. I would guess that they serve somewhat as a reserve capacity in peacetime, but mostly separate from the military side. No need to use a mil spec dozer to push sand in Iowa, or have a military employee doing it, basically it is a non military govt agency when doing domestic work. How they integrated in Vietnam, or into active military, I have no idea.
Read my post below sir.
I am in the boat with LeTourneau because back in those days,and even today the cables are better on a clearing dozer,ESPECIALLY if you are burning on top of the groung,far less likely to catch fire,faster response time and they will flip a stump out better once you get the hang of it.
I enjoy the discussion on the Army ties this dozer may or may not of had. No signs of green paint yet, but the back up beeper bolted to the CCU looks to have an NSN stamped on it, so there is something military I guess! I replaced the bearing cap on the diagonal brace. Found a used one through the Offroad Equipment website. Also got a set of liners for that side as both were missing. Spent quite a few hours drilling out the old broken off bolts but everything came out and original threads survived. The left side was loose and missing one bolt. Both sides are squared away, torqued down, and greased up now. Next up: - change all fluids - change all filters - clean all screens - adjust main clutch, brakes, etc - grease everything that can be greased - remove giant muffler for a straight stack, I just don't like the looks of the muffler and I wear ear protection regardless - make some new bottom metal for the battery boxes - new seats - learn how to run a cable blade machine
Main thing with a cable blade is to not get slack in the cable.
While you are under your tractor check the hard bar and the pads & plates plus both ends of bar where it sets on the track frames. Bad Bob
couple guys have said dont get slack in the cable and left it at that. What does an operator need to do to keep slack out of the cable? what is the hard bar and what would I be looking for?
Just mainly don't drop the blade too fast because it will hit the ground and get slack ,
"While you are under your tractor check the hard bar and the pads & plates plus both ends of bar where it sets on the track frames. Bad Bob" The hard bar is a beam that it attached to the underside of the tractor just behind the and below the engine where it attaches to the transmission. it is held there by and pivots on a single pin and extended out over the track frame one both sides. On my D6C it sits in/on a wear pad with guides ahead and behind to keep the track frame from being able to drop too far should you get the weight of of it. Basically it supports the front of the machine. Picture a walking beam that goes from one track frame to the other. It has a bushing in the center of the beam and wears on the ends that sit on the track frames.
I got to put some hours on the dozer. Spread out some shale I had hauled and piled up. I felt pretty cool running that cable blade. Unfortunately the hour meter didn't record those hours. When I remove the cap that is sticking out from the engine, perpendicular to the meter, I can see the end of a shaft turning. So it works to that point. Anyone know off hand what part usually breaks in those? I dropped the belly pans/skid plates this past weekend. They are so much lighter when a ton of dirt, grease, and sticks is cleaned out of them. Found an oil leak and a fuel line leak as I cleaned the crud out of everywhere. Still working on changing all the fluids and tinkering with things. Got a new set of seat cushions and arm rests from Finney Parts. They are perfect fit and a great price. Nice stuff.
I woke up my C a couple a days ago too, I'm getting anxious to play in the dirt It's been a good winter here in central Maine but the winter still drags on this time of the year. I'm ready to get out there and spew some greenhouse gases.
Drained the wet clutch compartment last night. Suction screen was clogged and sucked to the point of failure. Pulled out a bunch of pieces of what looks like clutch material? It is non-metallic. Anything I should be worried about? The clutch works fine. I was planning on opening the inspection cover on the top side to to have a look inside. Planning on replacing the screen and filling it with fresh Cat TDTO 30. Whoever thought a 1-1/4" allen was the right tool for the drain plug sucked! 3/4" or 1" square pocket would of been much better.
you're right,most of the plugs I've seen are square,maybe some of the really old stuff is hex.
Found a good crack in the right sub frame and welded it up
That is called the diagonal brace and that one has been patched before. Keep a close eye on your weld cause when that brace breaks it's pretty much a disaster! Your tractor don't have a hard bar it still has springs so carefully inspect them for loose bolts ,brackets and cracked spring Leafs. Bad Bob
If that is a solid piece of cast steel how would you ever weld it with enough penetration to ever make it near as strong as it was originally? If it wasn't welded entirely would it be expected to have near enough strength to hold up to the stresses that area is subjected to?
Cat sells a special tool made for those style plugs, it's around $25.00 bucks if I recall correctly, it's reversible and fits two different sizes of the hex plugs and is used with a 1/2 inch drive racket or breaker bar. I don't have the part # but the cat guru's here could find it.
It’s hollow and shows signs of welding being part of it’s original construction
Ok thanks, that would make it much easier to weld.
got to push some stuff yesterday! Woohoo
When I purchased my first new Cat, a D6C in 1966, it wasn't long before the Cat dealer organised a major modification for the diagonal braces on the D6C. I took the tractor back to the local Cat dealer and they plated the diagonal braces top and bottom with large sections of 3/8" plate, fully welded to the braces. The plates extended over two thirds of the length of the braces. The D6C had only done a few hundred hours at that point. The repair was carried out free of charge by Cat, so the Cat engineers must have come across a number of D6 tractors with cracked diagonal braces. The diagonal braces never gave me any trouble at all, and I sold the D6C at 13,000 hrs after much hard heavy earthmoving work - including ripping a lot of rock. I'd suggest plating your D6 diagonal braces would be a good move.
Tried to find the 1/2 inch drive version but I think this is an earlier version: Plug Wrench - Antique Caterpillar Machinery Owners Club If you have an interest in Caterpillar, ACMOC offers something for everyone. Through our full-color magazine, shows, local chapters, and bulletin board, members enjoy the camaraderie of shared interests. www.acmoc.org
OK guess I finally found it on SIS:
That hs the same end but with a handle, mine just the head like that with the 1/2 in ratchet squre made into both sides. That's more than I paid for mine, but will work fine even if you have to use a pipe to extend it for more leverage.
The transmission gear selection lever randomly pops out of first into neutral. Seems to happen randomly, pushing material or just driving. It's pretty infrequent, not a constant thing. Maybe once every other hour of operation. Is there an adjustment somewhere to deal with this? Someone mentioned something about a transmission interlock related to the clutch lever. I don't know if it does it in other gears, I only use it in first gear.
You need to get a service manual for your machine, it will show how to adjust the interlock linkage and all the springs and detents in the transmission shift controls. Bad Bob
Leadfarmer, here's the relevant information from the service manual to assist with adjusting and repairing the interlock mechanism of your D6.
Last page (I am only allowed 4 photos per post for some reason) ...
Many thanks!
Back to the possible interlock issue... I ran this dozer for a few hours today. Only once did it pop out of gear while moving (speed selector, not the direction lever). Most of the time I was struggling to move the direction lever (F-N-R) when I was stopped and trying to change direction. It felt locked solid and I had to keep working the clutch lever until the direction lever would finally move, and then it was magically free. It didn't happen all the time, but it happened most of the time. At one time I thought pushing in both brake pedals while stopped caused the lever to free up. Most of the time I was not touching the brake pedals because I was on flat surface. Maybe just a coincidence. So I referred to the reference material that was posted by OzDozer and I refered to the 44A service manual I picked up that is a little different in what it shows. The only adjustment given is the ideal length of the linkage for the interlock on the left side of the transmission that connects to the clutch lever. I confirmed this was right on the money. 4.6XX". Then I decided to pop off the cover over the plungers. Boy is that thing fun to work on. The end of the plungers that contact the shaft are worn on one side. They are all worn the same and the worn edge is facing towards the front of the machine. Are they supposed to be worn like this? No broke springs or plungers. Nothing jumped out at me. My first thought is to tinker with that linkage length, though the manual does not give a range of lengths, just an ideal spec. Any thoughts?
More pics
So after inspecting the interlock plungers and making sure the linkage is correctly adjusted, finding no smoking gun, I adjusted my operating technique. I have found that pulling back on the clutch lever slightly and hitting the brake pedals will free the F-N-R lever to shift. For now, this works. Broke my blade cable this past weekend so now I get to learn how to replace the cable.