hello, my new to me dozer has about 9700 hours on it and it has started to run away during shut down. we decided to give it an overhaul. after getting the heads off and belly pan removed, when draining the engine oil i noticed that it was nearly over-full and the oil smelled alot like hyd fluid i checked the operators manual and it appears the entire machine should be using engine oil for lubrication/hyd. im guessing when the last owner replaced the transmision they probably put hyd oil in. is there a common failure on these machines (cooler, etc) that could introduce torque converter/transmission fluid into the engine crank case? thanks in advance for any support, i'm hoping to have the pan off and liners out by the end of the week.
I would think Simon C may be able to give you some advice on this machine. Komatsu parts are going to be very expensive ( if they are available at all) but aftermarket may be the way to go. Keep us apprised on the rebuild. Pictures are nice!
Too be truthful I kind of doubt it has 9700 hours on it. Not sure about the year but trying to remember if you have the NH220 engine inside that unit. Hydraulic oil can enter the engine from the rear crank seal but generally since you have crankcase pressure in the engine with it running, the oil goes the other way. Is your transmission oil all black.? Now I cant say foresure on your D-65 as I have done some work on various 65 machines but I will say that on the larger 155 size machines they have frost plugs on the inside of the flywheel housing between the block and flywheel housing. They have been pushed out before by someone with a bolt 1/4 inch too long being installed from the flywheel side of the housing. That will dump transmission oil into the pan. Have seen multiple times. Also could be a bolt that was installed on a face inside the flywheel housing that is gouged where the bolt secures and oil could run straight into the pan. If the pump in the bottom of the torque is not up to spec the oil level in torque could get too high and then leaking through the rear seal. On 155's the little pump on torque has a suction screen that gets plugged. Not sure if your has it. Why are you going to over haul it as parts are pretty scarce on these units. If the rear seal is done the speedy sleeve could be toast if it has one. Better think hard before overhauling as it could become way more than you imagine. Post year if you know. Simon C
All I want to say is if genuine parts are not there, then run the other way is my suggestion. I have dealt with the Komatsu aftermarket and too many horror stories to type all day. Simon C
thanks for the reply. fortunately the transmission fluid is clean i want to say it is a 1977. what makes you say the hour meter is wrong? it is a nh220 and rebuild kits for the motor are easy to be had. they actually make the rebuild kit 30 minutes away from us here at AFA Industries. it is already sitting on my workshop table. i am wondering if the dozer has a scavenger pump like you are referencing though @Junkyard do you know why i am seeing transmission fluid in my engine oil? i was going to ask scrub puller but it will not let me tag him thanks again
1977 is 49 years ago. People did not buy those kinds of machines back in the day to not work 1500-2000 hours per year . You figure it out. Just take your losses and get rid of if not simple fix is my suggestion They cannot even supply seals for the torque on units that old. If you have enough ability to fix something that old with the worst parts I have ever seen, I would suggest you get yourself a truck and make the big bucks. Machine shops don't even have the tooling to fix the heads anymore, is my experience. Don't let me stop you, if your a better man than me then I will congratulate you when it is done and all fixed. All the best to you. Simon C
Wow' dash 6 D65, that is scarce to see now in the U.K. and we like old stuff, the engine is a Cummins built under permit by or was it for Komatsu? the dash 7 also had the Cummins NH220 in with the Dash 8 fitted with the 6D125-1, anyhow the engine, transmission steering case and F/Drives ran SAE HD30 oil the hydraulic system had SAE 10 all just like a CAT, your oil transfer problem is from one of the 3 pumps hooked into the back case , the steering and trans pump are both driven from the ends of the same shaft near your left foot the hydo pump being under your right foot, back engine gears do the driving, I still have all the service and parts manuals, the thing to not loose track of is the engine is set to Komatsu spec with most settings way different to the Truck 220 motor, the C.P.L. plate will need to be used as even the injectors are torque set low, I think it was 55 inch pounds, the Truck spec is 70 or more, the valve springs used to fail and can be changed easy enough on engine, the torque is a single stage with a Sprag Bearing fitted to lock up drive, the engine was "Mighty" and would do 30'000 hrs with good servicing as it was so down rated, the water pump could be rotated in its housing to give more or less flow, I used to work on the 65's a lot years ago, they are built to a very high standard, the transmissions could manage 20'000 hrs taking only minimal tools to pull to bits like a 17 mm spanner,hammer, screwdriver and circlip pliers, the engine comes out not to bad but the transmission removal is vastly improved with a steam cleaner.
That is true that the two pumps run off the same gear on left side botom of the block, but if one does leak it has to get through the rear housing seal to get into the engine unless there is something there I am not familiar with. The main Hydraulic pump is correct on the right side of PTO under your right foot. The problem is not how long they last, it is how much parts are still available. The Company I did alot of component rebuilds for still has one operating, couple scrapped, one thing goes wrong and not worth it any more. Simon C
There's the filter , number 10 , careful how you remove and re-install it . D155 filters have a bevel cut that has to be placed just right , no telling what this dozer has TORQUE CONVERTOR SUCTION LINE D65E-6 S/N 20295-UP [d65e-6c] Komatsu 144-11-11310 Part catalog k-part.777parts.org
Just looked at the picture, looks exactly the same on D155 models. Is it the same part, probably but not guaranteed. Good picture. Simon C