Fully Draining rear end fluid

[Wilsonrl48747 0]

I just bought a 312-8 for my son, and everything looked great on the dipsticks when I checked it before purchase. I got her home and was manually pushing it into the garage, with it out of gear, and heard a little click click click noise as I pushed it in. So first thought is something is wrong in the rear end, so I opened the drain plug, and the oil is sorta milky, but not as bad as I have seen before. I tried draining out the old fluid but as you know, the drain hole points up. I jacked it from the front and side to tilt the unit to try and drain as much out as possible, but obviously there still is old crummy fluid in the bottom "pan" area.

2 questions:

1. Is there a good way to totally drain the lower unit without renting a crane or without tearing the unit apart?

2. The clicking noise concerns me, I hope I don't have some imminent failure coming soon. The clicking speeds up as the tractor rolls faster.(Rode it down the front hill with gear disengaged, although now that I think about it, the HI/LO was in HI so it was not TOTALLY disengaged.) Could the clicking noise be something else?

Thanks in advance.

[TT-(Moderator) 1,145]

The angled plug you found on the left rear corner of the transaxle is actually the first-generation fill/level hole. (from way back before they used dipsticks)

If you look at the very bottom of the left case half of the transaxle near the rear corner (more or less below the plug you mentioned) you should find a pipe plug. You might need to clean the bottom of the case off to find it.... it's almost flush with the case and is made to use a hex key. ("Allen wrench") CLEAN THE HEX OUT before attempting to remove the plug and make sure your hex key is a quality tool. (not imported junk)

I can't help you much on the clicking sound. Perhaps it could be something related to the brake drum or maybe something in the differential or reduction (brake) shaft bearings.

[Duff 206]

Don't know if it's a good sign or a bad sign, but both the transmission on my already rebuilt and working 312-8 and the one I'm in the process of rebuilding have a "clicking" sound when free-wheeling. The working machine's gotten quite a few hours on it since the rebuild and the sound hasn't gotten any worse, nor has the transmission showed any signs (yet - ) of giving problems.

Good tip from TT about the plug on the bottom of the tranny - I didn't locate that until I'd already stood one machine up on its hind quarters to drain the tranny. That's a project in and of itself!

Good luck!

Duff

EDIT: Oh yeah, and like TT says - get yourself a good hex key and make sure the head of the plug is very clean so it seats properly. You may have to fashion a breaker bar of some sort to use with the hex key to get it to turn the first time......

[TT-(Moderator) 1,145]

Here's my "worth 1000 words" contribution:

(ignore the gaping hole under the differential )

[chamjack 0]

TT Posted on July 13, 2009 08:56 pm (ignore the gaping hole under the differential )

What in the world caused that????? That took some force to bust through.

[Wilsonrl48747 0]

WOW, Thanks so much for the picture, but yeah, what happened there??? Tell us so we can avoid seeing something like that someday! :thumbs:

[kpinnc 12,560]

Hey Wilson, check the dipstick to see if it's rubbing the bull gear. On my 310, the dipstick got turned around somehow and was rubbing the top of the bull gear. It also made a clicking noise when I rolled it around. Over time, it completely chewed the end of the dipstick down...

Good luck!

Kevin

[Wilsonrl48747 0]

:thumbs2: Thanks so much for the advice. I will check that. That might be the issue, it might even be the wrong dipstick for this unit, the guy I bought it from seemed to have a couple of WH's that he had cobbled together, and the dipstick was not seated all the way down. I figured thats how the fluid got milky, maybe some water got in it, so I wiggled it until it was fully seated. I know I didn't hear the clicking when I went out to look at it. If that's it, I will let you all know.

[TT-(Moderator) 1,145]

What in the world caused that????? That took some force to bust through.

That particular transaxle is the big "bulletproof" 8 pinion / 8 speed out of a 1986 417. The last guy to work on it didn't install new locknuts on the bolts through the differential and a few of them worked loose. (but only one came completely out)

The bolt actually caught on the inside of the case and bent up enough to pull out of the differential and then passed between the differential and the case. The owner of the tractor said he heard a "POP" but the tractor never stopped moving. On his return trip to the woodpile with the cart, he noticed a big oil trail and a piece of metal laying in the snow.... along with one slightly bent "long skinny" bolt. I think he said he hauled five or six more loads of wood to the house before he parked it and it still worked fine when he brought it to me for a "new" tranz! :thumbs:

[rwilson 128]

That sure is the easiest way to drain a trans that I have ever seen!! :thumbs2:

[frankiefiredog 1]

This post was very helpful, as I know my hydro trans pretty well, but haven't had to do any work on an 8-speed yet. Now I have some dripping from the right side rear axle... Not looking forward to this. Thanks for this post though. I'm going to drain and refill just to double check the leak.