Gday Guys

Great site you have here,

I have owned my D4 6U serial number 300 for the past 17 yrs and it is need of repair and I have a few questions for you please.

I have done a few searches (Pony Motor and Parts) but not come up with answers to my queries

1. I am trying to remove the Pony Motor clutch as the pinion seems to be stuck on, I am having problems removing the clucth assembly.

There just is not enough room to pull the clutch assembly out, The fuel pump gets in the way, I have removed part of the governor housing but there is still not enough room, Looking in the inspection hole for the pinion , it seems that when you try pulling the clutch out the whole pinion` assembly sleeve comes out as well, This makes the whole clutch assembly 12" or so, I would have to remove the fuel pump to get enough room, Is the sleeve meant to come out too? or is something stuck ? or am I missing something.

2. The pony motor is in need of a recon as it blows a heap of oil out the exhaust and the crankshaft end play is about 4mm ( Piston and rings and bearings and gaskets) Is it hard to dismantle the Pony motor and any special tools needed and are parts available?

3. The D4 has developed a major oil leak in the rear of the engine and it fills up the bell housing with oil, The oil is definitely coming from the diesel as the level on the dipstick will slowly go down over about 3hrs ( 5lts)
Could it be a rear main seal? what type of seal for the crank does my D4 have? and is it a big job to replace please.

4.Where do you Aussie guys get parts for the older Cat tractors please?
Here in Perth There is only Westrac ( not sure if Wildkat is still operating) about 10 yrs ago I asked Westrac for a Service manual for the D4 and they said it was no longer available and many of the parts for my D4 6U are not made anymore, They did manage to get me the last owners manual available though.
Things I need are fuel and oil filters, pony motor parts and gaskets radiator cap etc

Sorry for being so long winded , just I am am a little stuck on what to do and where to go


Thanks for the help

Cheers
Simon
Western Australia

Hi Simmon, Give tilley's crawler parts a call on 1800 076 280, They are on the east coast but will send parts all over the country and for that matter they also send all over the world. I normally deal with Drew. Happy hunting, Regards
Mark

If I remember right just the gov. rear cover removed gives you enough room to pull the pinion out and yes it s all in one piece, the clutch and pinion unless you just take the end nut off and take the clutch out piece by piece.The rear diesel oil leak is caused by the rear main bearing being worn as the crank only has thread type grooves in it to screw the oil back in and when the bearing or the crank too get worn the oil goes by the clearance and there is no seal back there but only the screw on the crank.On the clutch it seems if the little cover on the front of the clutch housing is removed along with the gov. rear cover it gives it room to coming out but you may have to twist and turn the clutch housing to get the right position for it to come out.If you take the whole inj. housing off it,s no big deal but turn the fuel off at the tank and you,ll need a new mounting gasket and a seal for the fuel passage to the housing from the filter base. You can,t get it back on wrong as the drive on the camshaft in the pump has an offset tang so can only go on one way.Better still you can jus remove the wole gov housing from the inj. housing but you,ll need to take the bolt out of the rack bar inside and then it wll come out.

The pony clutch assembly will come out by just removing the governor cover (with a fair amount of wiggling). Don't forget to have the pinion engaged as that gives you a slightly shorter assembly to deal with.

Hi Simmon, Many years ago I had a very late 7U, and had same problem, used to carry a pump to return oil to Motor!!. There is a seal you could get then from Cat, For memory it fit's the wet clutch on a 12E grader ,it came with instuctions how to fit as well. That almost completly solved my Problem. Big job though fitting it. That was about 25 years ago, I got that through Hastings in Dalby [ Now Closed ] and the spare parts fellow there I think new every part in those older machines of pat. He was brilliant. Good luck and keep us posted

First did you lift the poney motor about 2 inchs after you need to removed the screw from the inspection back cover rear the pinion cluch and take off the pinion end cover and you have removed the governor cover and the oil in the cluch should came from the poney crank oil seal and for the big motor the oil should leak by the pan gasket or the plug and for the poney parts am still have 1 use standar crankshaft and more parts.

Hi simon,
welcome to the BB.
If your rear main oil leak has gradually gotten worse over a period of time it could be crankcase blow by pushing the oil out past the screw (scroll) type seal used as note in other posts above. It is not unknown for the Diesel engine breather to block and not allow the blow by to escape thereby pushing the oil out---an easy check before doing anything drastic.
The boys as usual have given good advice on the pony pinion removal etc.
Hope this helps.
Cheers,
Eddie B.

Thanks for the help and info guys, much appreciated.

Depending on how much free time I get on the farm today, i will attempt another go at removing the pinion.

For the rear main oil leak. It happened all of a sudden. that's why I thought it may have been a seal or a welch plug. I remember reading somewhere that there is a $2 wick seal that may have gone, but I am not sure if that is correct with my model.

The tractor will only drop its engine oil If I travel up hill with it, on flat ground or down hill it won't leak,
I will check the engine breather for blockage

If the screw on the crank has worn, what are the options I have ?

Does anyone have a diagram or pic please of the rear of the diesel engine, so I have some sort of idea what plugs or seal are there.

The only major problems I have with the D4 are the pinion not disengaging fully ,the rear main oil leak, the tired pony motor, and a proper radiator cap and possibly the radiator re cored

The rest of the tractor is ok, the diesel runs perfect, chains are just ok, needs new paint

Cheers again for the help guys

Simon

Lance , was that fellow called Dennis ? the parts guy that new all those machines so well .

Hi D6pete, THat chaps name was Doug , can't recall surname. He was just one of those special Guys. Any help ?.