Leaking final drive on HD16DC

Howdy

This one stumps me. This past summer I noticed a small on the right side final drive. I think it was Cal that said check outer cover as sometimes a leaking seal will occur under the bearing cover and follow face of final drive and appear to be leaking somewhere else. Cal was right. I torqued to specks, emptied final drive and refilled with 80/90 gear oil per speck. No leaked anywhere until today. I saw oil under final drive same as before and checked level and was down substantially.

What would cause a leak to start up just sitting still for at least 2 months.

It did drop down to 0 overnight. Metal contraction?

The three threaded holes are Pusher Bolt holes to remove that assembly. Allis used a Particular Bladder type final seal, a Neoprene donut fiber reinforced with a internal and external steel squeeze plate spring loaded to keep the system under pressure to keep oil in dirt out. Check the parts lists at Minnpar if they do not have then do a Google search by Allis Chalmers and p/n. There may be a few still out there, I got the last known to exist for my 7G a few years back and nothing shows on searches anymore.


Have to remove the lower truck frame, roll it out of the way, pull sprocket then bearing support is accessible where that seal sits.

Just remember - if it isn't a bad leak the real problem is when it stops leaking

Thank you Ian. I won’t be able to power wash with steam until spring so tractor is sitting in barn. Hard to do much in an unheated barn with his time of year. I should the final drive does not leak entirely. Just goes down to roughly under the level of your finger. When you pull the cover plug off with a drive wrench, you can see down to where the lower level is. I filled it to the top of the plug and it’s down to the lower cavity. When I drained it this last time it looked like 2 or 3 gallons was still in the unit. That’s what led me to believe it was a cap or cover higher up. Thank you again.

Now that's a pretty good idea. Yes I have factory crankcase vents own top of each housing and would be easy to put under some pressure to see where it is leaking from.


Thank you DMiller. Will let you Ian know how that works out when it gets above 10 degrees.

gemdozer wrote: You should never fill the final drive to the top plug you can stop when you see oil in hole

I did not know that gemdozer. Would love to think I overfilled it.

Thank you . I used de greaser cleaner and wiped down the side of final drive and around the sprocket and everything I could reach. Will put a small amount of air pressure on the unit to see if I can find any telltale signs of fluid leaking.

1/2" bolts are 3/4" hex, is this what you are referring to?

If has been upsized may have also drilled too deep or too wide and cracked where the oil can leach out thru a crack.

Hey guys

On the final drive, how does the intermediate and pinion gear get oil? Is this a case that the main gear is lubed by the oil sump and carries it to the intermediate and pinion gears? Reason I ask is that the oil leak is not draining the entire final drive housing, just partially. I will add enough oil to bring up the previous level and will tell me how much I lost bs how much I added back. Total housing according to my manual holds 4.5 gallons. If I’m losing 1 or 2 gallons then there is still over 2 gallons in the lower housing. I think of it as an oil bath kind of a situation. If the main gear is immersed in oil does that get to the intermediate and pinion gears by a splash effect?

Just assessing extent prior to making plans to split the track, move out the truck frame and pull sprocket.

Thank you

CAL(KS) wrote: yes splash.  IIRC  there is a kind of channel built onto the inside of the case to help funnel oil to the inner bearing,  but its been awhile.

Thank you Cal. I will add fluid to see if I can identify the source of the leak for certain now that I have it all pretty cleaned up. Then determine how much was lost vs what the case holds. Might not be as bad as I feared. Will let you know. My thanks again.

gemdozer wrote: Yes just by splash and if you used to much oil in final drive it will  destroy the bellow seal

Thank you Gem. per the operating manual, I filled to top of fill opening. Sounds like in practice that is not a good thing.

Steve allis dozer wrote: MY HD11 leaks sometimes and then takes up doesn't leak for a while I just check the oil and top it up before use , i have heard of fencing wire getting wrapped around there . they don't like that !

Thank you Steve. Good advice.

CAL(KS) wrote: Steve allis dozer wrote: MY HD11 leaks sometimes and then takes up doesn't leak for a while I just check the oil and top it up before use , i have heard of fencing wire getting wrapped around there . they don't like that !    this happend to me on my 16.  I started loosing oil so i kept a close eye on it till i was finished up and able to haul it home.  turns out a piece of wire had been pulled into the gasket area of the seal and dislodged part of it.   a whole lot of work for 1 little gasket, but got it fixed.

Was this wire wrapped around the Sprocket Hub? Which gasket was impacted Cal ?

Thank you. I bet was fun job!!

1.  Yes