D6H transmission leaking into frame?

[tracksfan]

I've got a D6H serial #4RC10xx leaking oil out of the frame where the belly pan bolts are attached. its on the left side a few inches from the transmission case. Anyone else ever run into this? I've checked more than once to see if its a hose spraying oil onto that area, but everything looks good. It is steadily leaking more and more. maybe a pint or 2 a day. I will try to get a pic.

 

[JeremiahSr]

Wow! Never seen this. The rear does have oil in it for the transmission. The frame must be cracked internally where the rear and side main frames weld together. This is then letting oil in the hollow left frame and leaking through the belly pan bolt holes. I would hate to be the one to make that decision, seems how you would have to cut the side from the rear frame, repair, then weld back together. Unless the oil is getting in that hollow frame else where in the front?

 

[tracksfan]

some pics

Thanks for the reply. I was thinking that too except maybe weld it from inside the trans housing. I hate to cut on the outside of the frame. I have to remove the trans for some repairs and then maybe I can see where its cracked.

Here's some pics from underneath. The trans is on the left and the torque is on the right of the pics

 

[Per Eriksson]

Give it a good clean in that area.

Wonder what would happen if you drilled a small hole into the frame there, perhaps is starts to pour out oil......

 

[JeremiahSr]

That was bad advice from me before. You are right, the only way to fix it is from the inside after oil and transmission is removed. Sorry tracksfan.

 

[zspear1]

I had a D6H doing that awhile back and it was the Hyd valve body way up on top. I also saw another one leaking the other day and we took the floor plate out and it was the transmission pump leaking.

 

[tracksfan]

update

Thanks for the replys. I didn't think of the hydraulics leaking into it. I'll check for that. Although I'm pretty sure its the trans.

After draining the trans I drilled a hole into the lower part of the frame and sure enough out poured the oil. 1 or 2 gallons

Sure looks funny without the blade and tracks

Working on removing the trans next.

All for now

 

[tracksfan]

pics of trans removal and crack

I pulled the trans out using a floor jack. the green bracket and chain were for added safety more or less. The trans slides out on rails, this is a nice design.

There was and inch of dirty looking oil in the bottom of the housing. 5 gallons or so. I cleaned all that out. I think it would be better if removing the drain plug actually drained out all the oil.

The crack is the black streak a inch or so from the corner. I thought the weld would be cracked but not so. its around 5 inches long.

Have you seen this before? what causes this? I'm easy on the machine but who knows what its history was before i got it.

Now I wait for the welder/mechanic.

 

[tracksfan]

update

Also had to do some work on the transmission, steering clutches and brakes. Some of the friction disks, plates and pistons were worn and needed to be replaced.

pic 1, the crack is welded up

pic 2, a rubber friction disk from the trans, not a great pic but you can see the deteriation. those lines should be much sharper looking

pic 3, one of the old retainer plates with grooves worn in from the brake/steering clutch and a smooth new one

pic 4, putting it back together, hard to get those all those teeth to line up

 

[cps]

Never seen one of those crack, thats a new one to me!! Nice work on the repair.

 

[Gavin84w]

Pay particular attention to cleaning out the debris from the weld process and seal it up by painting too. Last thing you want is any small bits of slag going through all those new tranny parts!

Install a clean out filter in the trans and run it for a few hours like that and then install the std filter and change it out after a couple of days, cut them both open to see how things look. May even pay to give it a fresh lot of oil at the same time as doing the 2nd filter.

 

[That_Fulla]

Thats good stuff. Seeing cats all pulled down is quite informative. This is sort of one to put into the back of the memory. Good advice from Gav too. 6H is a dam fine cat!

 

[tracksfan]

Thanks for the replies,

Gavin84w, we are thinking alike on this. I cleaned it and painted it.

I put it all back together, filled it with oil and a put in a high effeciency filter.
When I started it the trans filter indicator light came on. I thought, ok, cold oil it will go off after a few seconds. It just stays on. Now I'm more than a little frustrated after all those repairs that I still have problems. I don't know if its the wrong filter or if there is something else hindering the flow of the oil. I don't have the filter # with me. Its a different # than in my book due to a changeover. I run TDTO-4 30W and the weather is in the 30s.

My next step is to pull out the filter and inspect it. Pressure tests?

Also its not shifting into the forward gears everytime. I'm guessing an adjustment to the linkage may help. These are quick tests done on the shop floor I'm not running it in the dirt.

Any thoughts or advise is appreciated.

First pic, trans taken apart, lots of parts

second pic, trans repaired and put back together, tipped up on end before installing the bevel gear case.

third pic, both finals with steering clutches and brakes repaired and ready for installation.

Thanks all

 

[Per Eriksson]

No forgotten rag in a tube or hose somewhere?

Check pump pressure at the steering/brake valve, and then on the rear cover of the trans and go from there.

If the pressures are ok then the hesitation in shifting might be cured by changing a spool and slug in the control valve to an updated version.

 

[Gavin84w]

Thanks for the replies,

Gavin84w, we are thinking alike on this. I cleaned it and painted it.

I put it all back together, filled it with oil and a put in a high effeciency filter.
When I started it the trans filter indicator light came on. I thought, ok, cold oil it will go off after a few seconds. It just stays on. Now I'm more than a little frustrated after all those repairs that I still have problems. I don't know if its the wrong filter or if there is something else hindering the flow of the oil. I don't have the filter # with me. Its a different # than in my book due to a changeover. I run TDTO-4 30W and the weather is in the 30s.

My next step is to pull out the filter and inspect it. Pressure tests?

Also its not shifting into the forward gears everytime. I'm guessing an adjustment to the linkage may help. These are quick tests done on the shop floor I'm not running it in the dirt.

Any thoughts or advise is appreciated.

First pic, trans taken apart, lots of parts

second pic, trans repaired and put back together, tipped up on end before installing the bevel gear case.

third pic, both finals with steering clutches and brakes repaired and ready for installation.

Thanks all

Better than even chance the clean out filter is causing the bypass light to be on, try it with a std filter but maybe give it a 2nd filter in quick succession, say after just a few hours running. Probably the light should not stay on even with the high eff. filter but combined with cool temps etc this will also contribute to sluggish performance, bear with it let it warm up nice and check oil levels etc and maybe a couple of pressures too, after all it has all been apart, just run through the basics first.