View Full Version : d6b 44a questions

10-09-2009, 03:07 PM
I put this on another post but decided that it might just be better to start a new thread since the other one was all wrong.
I went today to have a better look at the dozer. it is a d6b 44a. the undercarriage is in really good shape at least 85% I would say. The blade is a 9 foot straight blade with tight pins and good edge although it does have a hole in it now where they tried to push it with another dozer. The engine is stuck right now but the fellow said that three days ago they put batteries in it and it turned about 1/4 turn before it stopped. I am wanting to get it running does anyone have any suggestions? If for some reason I cannot get this running I am going to sell it either in part or whole. Any info you guys can give me on the machine would be greatly appreciated.
right now I am not looking for parts I am just going to give it a shot at getting it running. Hopefully.

Deas Plant.
10-09-2009, 04:52 PM
Hi, Crazylegs.
That '1/4 trun and locked' sounds as if it might be a hydraulic lock - water in a cylinder. Pulling all the injectors and turning the engine by hand may give you a clue.

Old Magnet
10-09-2009, 05:05 PM
What's the serial number??

10-09-2009, 05:08 PM
First thing to do is to see if the radiator is full and the engine oil is full. If low coolant or high oil level (above the "engine stopped" mark), you may have problems other than the stuck engine.

One good way to check things is to loosen the drain plugs on every oil filled compartment and drain any water present. If more than a drop or two, (and a good idea anyway) drain a sample of the oil to look for metal flakes/chunks of gear etc. That way you will have some indication of the condition of the tractor before you sink a bundle into it to get it running and then find that you have a damaged final drive for example. Also a great time to drain any water and sludge from the fuel tank drain and change the fuel filters.

The D6B is an updated version of the 9U tractors with the D333 engine instead of the D318. The hydraulics are integral to the tractor, with a pump gear driven off the front timing gear/accessory drive of the engine and the tank and valves installed in front of the firewall instead of an add-on all-in-one unit hanging on the front of the tractor.

On the stuck engine, the first thing I would do after checking for/draining any water from the oil pan is to remove the injectors and put about a cup full of your favorite penetrating oil in each cylinder through the precombustion chamber. Then get a big ratchet or breaker bar and a socket to fit the bolt on the front of the crankshaft pulley and try to work the engine back and forth and a little bit farther each time until you can go all the way around. Probably also a good idea to remove the valve cover and check that the valves are not stuck so you don't bend one as you turn the engine. I don't think this is real likely to be a problem, but wouldn't take long to do. Look for any valves with excessive clearance.

Many times you will be ahead to remove the head and take a good look inside even if you can get it loose. You may have some serious pitting corrosion in the sleeves and stuck rings that you will end up having to deal with sooner rather than later.


Taking the head off is the first step to an overhaul!:D

10-09-2009, 06:10 PM
That is some good info thanks. The hydraulic lock crossed my mind but not from water because everything is sealed or so it seems from the enviroment The oil is black looks good maybe a little high but not much the radiator is not completely full the thermostat was removed to get to the fan shaft? (that is my next question) but first. I hit the ignition and you can see the crank bump at the pulley but it does not move. Tomorrow I am going back to remove the glow plugs or injectors maybe (how hard are they to take out on these?) and put some tranny fluid in the cyl. and work it a bit to see what will happen. Old magnet the ser. is.44a6470
A little history on this thing according to the seller his step father and a friend went in and got this thing and the deal was that if Dad would operate it and if something broke the friend would buy the part and dad would work on it and fix it or pay for labor. Well the shaft for the fan broke? (that is the question I had because I have no idea what he was talking about here). They called cat and it was going to cost 500-600 to get the part. the friend didn't want to spend that money so he got a machinist friend to make it. well he didn't use good enough steel and it twisted again. They got into a huge fight about it and have not talked to this day. Now what I know is the parts that are removed are fan thermostat and hard nose cross shaft. Oh and the shaft that twisted but I can't find that so I have no idea what it looks like or where it goes to even get an idea what to look for.
that is the whole story sorry for the long winded version.
thanks again

Old Magnet
10-09-2009, 07:26 PM
The D330 and D333 had lots of problems with water pumps and they went through several changes. Unfortunately I do not have the parts book for your sr. #. I have early 44A1-up and later 6856-up but I suspect you have one of several versions in between.

The last version is a 2S5597 water pump group but I can't tell you for sure if they interchange although I would tend to think they would.

Yours is a 1962 model.

There is little or no load on the pump but over tightening the belts and the long nose pulley on the D330 was to much for the early shafts.

10-09-2009, 07:31 PM
how can I tell if I have the d333 or the d330. From something that I read I thought it was the d333 but I can't remember right now what made me think that.

Old Magnet
10-09-2009, 07:36 PM
D330 is 4-cyl, D333 is 6-cyl. Sorry, didn't mean to confuse, just covering the engine family:)

10-09-2009, 07:43 PM
whew thanks I thought I had to start over on my research. would there be that much difference in the water pump on that? I am not sure that is what he is talking about anyway because the pulley is still on the shaft and the belts are loose so I spun the pulley and best I can tell it is good. Keep in mind that this is second hand info that I am getting so he may not be right on his nominclature that was a big word I need to go lay down.

Old Magnet
10-09-2009, 08:34 PM
Nor sure I am following you....the water pump shaft and pulley is also the fan support shaft and yes there were several evolutions of the shaft and bearings.

10-09-2009, 11:34 PM
no matter what, you will be at least pulling the head! what drives the
waterpump. is it gear drive like a 3306, or is it belt driven. no matter
how it drives with no fan it got hot! you most likely be doing a major
on this engine if it stuck due to water or antifreeze in a cylinder from
a cracked head.

10-10-2009, 02:58 AM
ujoint, The engine was not run without the fan, the fan was removed because the fan shaft got twisted. The fan shaft is what I am not understanding because it sure looked to me yesterday like the fan would bolt right on to the pulley.

Old magnet you are following me precisly I don't understand either because that is exactly what I was thinking when I was looking at it. But the guy is persistent that there is a shaft for the fan and it got twisted or bent.

Now this morning I was laying there thinking about it and I think he may be right there may be a shaft that bolts to the front of the pulley to extend the fan out closer to the radiator and maybe also to give clearance for the hard nose cross shaft. does anyone have a book on it to give me an idea if that is right?

10-10-2009, 03:00 AM
It is a belt driven water pump ujoint sorry I missed that question.

Old Magnet
10-10-2009, 10:47 AM
There is a fan belt adjuster involved...I wonder if the owner is referring to that.
It is possible to bend the bracket.

Here's one of several water pump variations
The adjuster.

No extension involved.

10-10-2009, 03:57 PM
Ok, I went back out there today for a bit to try to get that thing going. I pulled all but one injector and I broke my breaker bar on it and didn't have another way to pull it so I pulled the glow plug to relieve any fluid lock possibilities. there was no fluid in the cylinders but the injectors were wet with diesel fuel which suprised me a little. I filled the cylinders with as much diesel fuel as I had with me. I pulled the starter to get to the fly wheel to try to move it I can only move it about a quarter inch in either direction I do know that one piston is moving because it pushed diesel feul out the pre cup (just spurts) that is the only one that did it so I am not sure what is going on there.

So I called the guy and keep in mind that he has no reason to lie to me and I believe him when he says that when they first hooked the battery up that the engine turned over one quarter of a turn and then stopped dea and would not move again. he did say they had four batteries hooked up two set in parellel and the sets hooked up in series (24 volt starter) I don't know if that gave him more cranking amps and it pulled a piston apart or what.

Do you guys have any thoughts on that?

old magnet I also ask the guy if he could talk to has step dad and find out exactly what it was that was bent or twisted so hopefully I can get some better info.
thanks all...

10-10-2009, 04:04 PM
I do have one more question. what is a d6b running with a really good bottom worth. the reason I am asking I think I can get about 1800-2000 from a local equipment scrap yard and I don't know if this is even worth fixin. if I can only get 2500 from it then I will just let them have it and be done with it. if it is worth more then I will give it a good effort to get it running.

Old Magnet
10-10-2009, 05:46 PM
The first thing that comes to mind is rusted up cylinders. How long has this thing been setting? The early stages of rust will sometimes let pistons move but then they lock up....soaking may get recovery, may not.

As far as value, it has to run to be worth anything more than scrap. Any additional value would come from condition of undercarriage (real measurement), blade, hydraulics etc. At best they were not one of Cat's finest with the D333 prone to overheating, cracked heads and spun main and/or rod bearings. Might be able to achieve $5k -6K if all is good depending on value and demand in your area. Segmented sprockets would be a bonus.

No, your not likely to tear up a piston with direct start....but you can break rings and bugger up ring lands in rusted cylinders if you force it.

Unless it comes free easily your looking at removing the head.

Deas Plant.
10-10-2009, 06:03 PM
Hi, Crazylegs.
If you decide to go ahead with this, as Ujoint said and Old Magnet, you will at least need to lift the head and have a look in there to see what the problem really is. I am NOT a diesel mechanic but I would not bet that it is not diesel fuel causing a lock either. A leaking injector, a full tank of fuel and standing for a while might leave enough fuel in a cylinder to cause that.

What does concern me a little is when you say that you can only move the flywheel about a 1/4" EITHER way. I can't see any form of hydraulic lock, either water or fuel, causing that. What has happened to take it from moving about 1/4 of a turn to moving about a 1/4"?

I think O.M.'s assessment of the value is pretty spot on. You may make a bit out of it selling parts from it, depending on the condition of said parts.

Don't give up just yet. Keep looking for answers.

10-10-2009, 06:29 PM
one thing is for certain deas I am persitent probably to a fault. I don't like giving up if there is a shimmer of hope. It is definitly not a hydraulic lock I had all the cylinders open I am thinking now that it is rust and I am trying to round up some help for monday to go pull the head off how much do you think that thing weighs anyway surly not more than 200lbs.? If I do get the head off on Monday what would you guys recommend as the first course of action to try to get it broke loose? A mallet and wooden block to jar them loose and hone the cylinders if it works?

Just out of curiosity is there anything else that might freeze up that might cause this I know the Generator is froze up but the fan belt is off so that is not holding this it is a gear driven hydraulic pump are they pretty reliable. just wondering (thinking outside the box)

10-10-2009, 06:33 PM
om the best they could come up with is it set for about nine years You couldn't tell it by looking at the thing it looks really good.
where can I find the measurements for the track so I can see exactly what kind of shape it is in?

10-10-2009, 07:17 PM
crazylegs - Engines are the relatively simple and lower-cost fix part of crawlers. If the undercarriage is in excellent shape, it's worthwhile persevering with the engine repair, to get the tractor running again, rather than scrapping it. If the undercarriage is shot, scrapping is the viable option, because undercarriage rebuild will run into more than the tractor is worth. However engine repair rarely runs into more than 25% of tractor value.

It appears that you are being set with more hassles than needed, due to the previous owners family problems and poor approach to repairs. Finding the missing parts is vital before you continue, or you will need to outlay some serious $$'s to purchase them.

The head weighs around 150 lbs, it's a 2-man job to lift it off. Commence with some penetrant in the cylinder bores as soon as possible. Yes, other areas such as flywheel and clutch have been known to jam the engine from turning. Look for critters nests, nuts, or even dropped tools and bolts that might be interfering with flywheel and clutch rotation.

The track needs to be tightened to measure internal wear accurately. This track uses a 6.75" pitch, so the pitch (pin and bushing internal wear) measurement (over 4 links = 5 pins), new, is 27.03". 100% worn is 27.51".

The track chains should use a link P/N of 2S5959 or 2M 8663, unless later design track chains are fitted. These P/N links have a rail height (measured squarely from the underside of the track shoe) of 4.00" when new. 100% worn rail height is 3.63".

Old Magnet
10-10-2009, 07:54 PM
I have two pieces of info on cylinder head weight:
Cylinder head bare....160 lbs.
From the 44A service manual it's stated as approximately 325 lbs and of coarse they recommend a suitable hoist. It's not just the weight, they are plenty awkward to wrestle with. That's a job for a backhoe or loader, not worth wrecking ones back:)

Deas Plant.
10-11-2009, 12:15 AM
Hi, Crazylegs.
I have lifted a new Cat D9G bottom track roller on my own at 356 lbs. I can assure you that there is NO way that I would try to lift that head off at 325 lbs - too many things to hang up on you. A bit of rust around a bolt, the gasket stuck somewhere and you have a back injury or something.

At the very least, make up a tripod out of 3x3 or 4x4 timbers or some suitable pipe or RHS steel tube and use a chain lift or block and tackle or a come-along to take the weight. Have some sacking or some timbers on one track to lower it down on when you get it off - believe me, it can be awkward trying to put something there to lower it on to when you have all that weight on your hands, even if you are only pulling it sideways.

I actually prefer the tripod idea as it is more steady and more delicate that using an F.E. loader or backhoe, unless you only use the machine as a lifting attachment point to anchor a chain lift or similar. Even then, you still have the problem of hydraulic creep unless you prop the boom up with something pretty substantial.

I'm not familar with the flywheels and clutches on the D6B's but, following up on OzDozer's mention of the possibility, it might be worth removing any inspection covers on the clutch housing and checking for 'foreign bodies' or loose objects in there that might be fouling the works before you pull the head.

I keep coming back to that 1/4" movement either way bit. If you had the clutch disengaged when you tried that movement, it means that the problem pretty much has to be in either the engine or the flywheel/clutch housing. A stray bolt wedged under the flywheel could easily cause that.

Happy hunting and best of luck.

10-11-2009, 03:52 AM
Thanks Oz, OM, and Deas. That is all great info. I am planning on going out there Monday morning. I do not have access to a hoist or any equipment where the thing is located, it is about an hour away out in a muddy field my backhoe is only two wheel drive and I am pretty sure it will not make it back there let alone back out at least right now. The plan right now is to get the head off on Monday if at all possible. I will have to give it some thought as to how to do that.

I have the starter off I wonder if something was jammed in the clutch if I could see the gears wanting to turn by looking through the starter hole. just a thought. We are planning on pushing it up on the trailer if it is a bolt in the clutch I will know it then. just thinking out loud here.

Deas Plant.
10-11-2009, 06:44 AM
Hi, Crazylegs.
If you can get your hands on a couple of good 2"x6" planks about 8 feet long, a decent hydraulic jack and some 1/4" to 3/8" chain or good rope, you may have enough to lift that head. Nail, or better, bolt the planks together with 2"x4" spacers between them to give you a beam with a 4" gap between the 2 planks. 3 of these 2x4 spacers should be enough, 1 either end and 1 in the middle.

Lay this beam across the gap between the hard nose and the firewall. Place the hydraulic jack on top of the beam. Pass the chain or rope up through the gap in the beam, over the top of the jack and back down through the beam.

Many Cat heads are fitted with lifting lugs. If yours doesn't have them, you will need to improvise - safely, I hope. Lifting eyes screwed into rocker cover bolt holes or whatever works safely. Attech your chain or rope to whatever lift points you have, tighten it to remove all the slack and start jacking.

I dont know if the head on that engine is help down by studs and nuts or by bolts screwed into the block. If they are studs and nuts, you will need a jack with enough lift height to at least get the head up far enough to pack it with timber across the top of the block so that you can get another bite at it.

I have used this method to lift the head off a Cat 769A dump truck - beat the heck out of trying to lift it by hand.

Happy exploring.

10-11-2009, 07:49 AM
I've lifted the heads off my old D6C's many a time (same engine) without lifting aids .. and they sure aren't light. I never thought they'd make 325 lbs. However, the brother and myself used to get them off O.K. .. and neither of us are built like Arnie. EVERYTHING is heavy when it comes to crawler tractors .. :)

The major problem, is when you come to re-install .. because there are a big heap of small brass ferrules that have to be lined up when you re-install .. and that head has to go back on .. straight, slow, and LEVEL.
Any misalignment, and you'll crush a ferrule, and you have to pull the head AGAIN. In addition, you often don't realise you've crushed a ferrule until you have a serious leak, right after startup .. :(

This basically means you have to utilise some kind of lifting aid to re-install. A pipe tripod utilised along with a small come-along or chain fall, would be my choice.
The head uses bolts, not studs, so there's no head guidance as with studs. You can acquire/fabricate and fit a couple of guide studs to aid re-installation.

Old Magnet
10-11-2009, 09:56 AM
Also add the following to your undercarriage measurement:
Grouser height.....new 2.12 in.....100% worn at 0.88 in.
Bushing diameter....new 2.12 in.....100% worn at 2.00 in.

10-11-2009, 10:56 AM
Deas, the 44A has a D333 engine so they have bolts in them, not studs and nuts.When dropping a head down on if you can come up with a couple studs to screw in it makes it easier to get the head to drop down straight in place as I always used them at the shop and then the ferrules and seals line up perfect then too with the head.

10-11-2009, 03:24 PM
I am wanting to get back there and work on it again I can't wait until tomorrow especially to measure the undercarriage I want to see what it is at and see if the diesel did its job on helping to loosen up the thing. I may just have to wait to get it here to lift the head off I can't see messing something up just cause I am in a hurry especially my back I can't just go to the cat store and get a new one of them even at there prices.

Old Magnet
10-11-2009, 06:25 PM
I like your thinking:) :) Back replacement or other buggered up body part repairs just ain't worth it. Hard not to get excited I know but it will be there for another day.

10-12-2009, 06:18 PM
Thank you to all that helped me out on this project. I went out a measured the tracks and they were not in as good a shape as I thought they were about 50% I tried again to unstick the motor to no avail there was a d6r there and he pushed me back and I tried engaging the clutch to see if that might jar it and it did not the tracks just slid. A fellow showed up that I called last Fri. to see if they were interested in buying it to part out and he bought it. I may have made the wrong choice by doing so but a bird in the hand is worth two in the bush.
thanks again for all that contributed to my quest I am on to my next project who knows where that will be.

Old Magnet
10-12-2009, 08:04 PM
That happens a lot with undercarriage assessment.....looks good until ya get the measuring stick out:) :) Not a great loss....but you'd got more flak if it had been a 9U;) ;)

10-13-2009, 04:50 AM
I could definitly see a difference in the grousers when we were moving it around there I noticed one that was different. it turned out to be almost new and it really stood out.

I am a little dissappointed because I would have liked to see the thing running but that fellow saved me a lot of time and with winter coming on really fast I do have some other things pressing so.

speaking of other things I am going to start another thread I have problems with my d4 pony hopefully someone knows something about what it might be.

thanks again

10-13-2009, 10:12 PM
old magnet.
you always have good advice and help many here on this site. i cannot agree
with your D6B opinion. i would throw rocks at a 9U over a B. this area is
littered with ag 9U's 47A's and 98J's. everyone of them are hot rodded to hell.
you will not find a 9U in this area under 125HP. they all have turbo's and
motor grader pumps turning 1800 RPM's. D6B's are cranked to over 140HP.
98J D5's will be 140 or up. they run there all day, day in and day out. i have
never known of a D6B to loose its bottom end or overheat without a serious
cause such as no oil or radiator issues.

i talked to my cat friend about the above. in his opinion they cannot be
compared. he said when you started running more horsepower, the B's or
the D333 would take it better than the 9U's D318. cranked D318's will wear
the timing gears due to the excessive RPM's. they are known to drop their
liners, when this happens your done. the block can be machined for an
insert but that will drop also in a matter of hours, due to a lack of material
in the block surface. if this happens, you will need to find a good block.

the B's D333 can also drop a liner as well as any engine. but cat has what
is nicknamed around here as a Z insert for the liners of the D333. i asked
my friend about the water pumps. he said he has only seen two of the
earlier style. the dealer in this area was on the spot to get them converted
to the later style before any farmers could have any problems. you drop a
liner in a B, your block can be repaired, you will not be looking for a block.

i have never known anyone who does not like the B, or the 9U as far as
that goes. there are two camps in this area. those who support the 9U and
those who favor the B. the majority goes towards the B. there are a few
idiots like myself who like the 98J, but the B wins hands down. unfortunately
not many of them still farming, challengers and wheel tractors have taken
over. you will find many repowered 9U's around here. i have seen one with
a 3306, most have detroits but i have yet to see a B repowered.

one thing they all share is the finals. the two 6's and the 5 running this kind
of HP limit the finals to 5000 hours. after 5000 hours you will be buying final
drive bearings.

10-13-2009, 10:59 PM
found these!

Old Magnet
10-14-2009, 08:58 AM
What's to discuss, your comparing highly modified units, the fact the 9U's can withstand such alterations attests to their durability.

Can't even find a B in our area and there are damn few D4C's. Part of the reason is there weren't that many produced and the other is they went to the bone yard a long time ago. Not until the D333C engine version did reliability improve. The early engines with lighter castings along with the elimination of doweled bearings did most of them in.

In short, you won't find an early D330 or D333 anything in my stable:) :)