Morooka MST800 final drive parts book

[darinray]

Hey guys and gals,

Got me a MST800 I took in on trade and am looking for a parts breakdown on the final drive. These hydrostatic transmissions I have no parts manuals on and sure could use a copy or a book.

I have a final that is leaking between the hydraulic motor and planetaries and want to see what I'm in for before starting.

Darin

 

[willie59]

Hi Darin,
I have worked on quite a few Morooka's of different models. I have a parts book at work, but I won't be back there until Monday. I haven't done the seal between drive motor and planetary on an MST-800, but I did an MST-600V just about a month ago and it's a good chance the setup is pretty much the same, just can't say for sure. What you most likely have is a floating seal (duo-cone seal) on the inside of the planetary hub and the seal life has reached it's end, that's what was wrong with the 600 I just did. You have to remove the track and get it out of your way to disassemble planetary. The 600 I just did had the sprocket bolted to the flange of the planetary hub and the sprocket was two piece. With machine blocked up, I just rolled the sprocket to where I could remove one half, then roll again to remove second half, made track removal a lot easier.

For parts, the OEM dealer in the east is Dominion Equipment Parts in Virginia. Brian is the parts manager.

http://www.dominionequipmentparts.com/

Another you should call and get prices is Lanway Tractor in Oregon. Talk to the owner Don Lanway, tell him I told you to call. I just ordered a salvage dump bed control valve for an 800 from him today. Sometimes he can beat the OEM prices, sometimes it's the other way around, but I always give him a shot at it.

http://www.lantraxco.com/home

 

[darinray]

Thanks a bunch for the information. I was afraid I was going to have to get teh duo cone from the dealer. I was hoping for a normal seal that I could cross or something.

This is the first Morooka I tore into so it is a learning experience to say the least. These tracks are heavy compared to the little Komatsu dozers and mini excavators I normally work on.

We took the complete final drive off the machine and are trying to get to the duo cone seal but have to wait now for my replacement large size allen head sockets to get closer to the seal. I am wondering if you could give me the teardown procedure on these finals. You see we are not sure how the hydraulic motor is attached internally to the planetaries.

We took the tracks off
drained oils
removed hydraulic hoses on hyd motor
took the bolts off and remove complete unit
remove planetary face and planetaries
now we are at the allen head bolts... Are we doing this right? Sorry to be pain but I am not sure.

Talk to you again and I do appreciate your help. W

Darin

 

[darinray]

Are these duo cone seal something we can't get aftermarket?

 

[willie59]

I haven't been into an 800 yet, here's some pics of the innards of the MST-600V planetary, see if it resembles what you have.

 

[darinray]

Nice pics. They are different maybe due to year difference or maybe model difference. Once I get the allen wrench back I should be able to get closer to that darn duo cone seal. It's funny because the parts book I got is only about 20 pages and shows the final drive complete only... no breakdown> Maybe Dominion can fax me over a breakdown when i call them. Thanks again and have a great one.

Darin

 

[willie59]

Yeah, Morooka diagrams are a little lame.

I would think you could remove the planetary hub without disturbing the motor. As for the cone seals, I'm sure there is a size out there that would work, I've just never found a way to find them. I've talked to a buddy at HeavyQuip about these things. Originally a Cat design, the cone seal of various sizes are used by practically all dirt equipment makers, so I know the sizes are out there. The problem is, I haven't found a size cross reference for cone seals. They are identified by machine application.

One thing you need to check on a Morooka is the trunion shaft bearings for the lower rollers. The trunion shaft is the shaft that attaches the triangle plates of the rollers to the track frame. I have worked on a number of Morooka's that the user allowed these bearing to fail, then the shaft starts wearing into the bearing housing that's welded to the track frame. When this happens, you have to cut off the damaged housing and have a machine shop make a new housing tube to weld on machine. I haven't seen many failures of the bottom roller bearings. They have oil in them and are sealed by cone seals.

 

[darinray]

Once we have this apart I'll see about the sizes or actually probably send them out to be spec'd. HOPEFULLY.

I'll check those trunion shaft bearings while the machine is down and out. It sure doesn't sound like fun replacign those housings.

Darin
www.dmmsales.com

 

[willie59]

Your 800 may be different, but the 600 I did had a typical profile cone seal on the planetary hub, but the mate on the track frame was flat, it didn't have the angle that a cone seal has, never see that before. And yes, these things can get a little spendy.

The trunion shaft design is, in MHO, a poor design on the Morooka machines. The shafts have grease fittings fitted on the outboard end of the shaft, but inserting grease does not work well because the shaft seals fit so tight that they don't allow air or grease to escape, they are a "two piece" type seal. Which makes sense if the objective is to seal tight enough to not allow ingress of dirt or water from the outside. But, when a seal is this tight, it will not allow grease to be injected to the inside because the old grease cannot escape because of the tight seal. If you have any looseness of any of the shafts/bearings, you should consider fixing it before you have bearing failure. Yes, replacing the bearing housing tubes are a PITA. I must add this though; some models, like the MST-1500, use either bearings for the shafts or brass bushings. I don't know if the 800 used bushings. Point is, a small amount movement on a bushing may be Ok, bearings should have no loose movement. What you should be looking for is if you can place a long prybar under the triangle plate, between bottom rollers, and lift the plate more than a 1/4" (movement of the trunion shaft), then you should check it out.

 

[willie59]

For those who have no idea what a duo-cone seal is, here's a link to show you what they look like. They are two precision lapped steel rings that "face up" to each other. They use an o-ring on a ramp to keep the rings faced tight against each other. The face of each ring is ground on a taper/angle. As dirt and abrasives wear the ring, the taper of the rings constantly moves the seal surface inward on the rings. When the wear reaches the innermost part of the surface, the seal is done.

http://www.kello-bilt.com/index.php?option=com_content&view=article&id=71&Itemid=112

 

[smellyseal]

i am wondering whether your problem solved, if not, you can tell me the ID*OD*H of the duo cone seal, maybe i can find some more detailed dimension, cause we are a professional manufacturer.

 

[lantraxco]

MST-800 Floating seal and collar

Hey guys, Dr. Don here from Lanway Tractor... I can email or fax a parts breakdown of the travel motor if anybody needs one.

The three allen bolts come out, the inner planetary assembly is on three dowels also which are usually tight as hell. I usually use some bolts in one of the flanges to force the hub off the travel motor half. There are shims under there that set the bearing preload.

The rotating hub has a floating seal half in it, the stationary motor half has a square cross section "Seal collar" in a groove. The only way we've found to get these buggers out is to drill a couple small holes from the backside right up next to the shoulder and then use a pin punch to drive it out. The o-ring seals on the ID, so the little punch holes you drill are harmless.

I stock the floating seal halves and seal collars, though I am currently out of stock on the collars. Probably be a week or two from order to get one in, if you actually need one. Sometimes all you need is the floating half. Get prices from Dominion, then after you've had CPR, call me at 888-452-6929 toll free. My prices are merely exorbitant, not actually insane. I can also get the big tapered bearings reasonably priced.

Oh, and let's not forget the hydraulic motor seal while you're in there, and if you need brake plates and gaskets for the motor, I got those on hand at good prices also.

Happy to help any way I can,
Lanway

 

[lantraxco]

Hey ATCO! Yeah, the old bearing style pivot shaft setup kinda sucks, bad design. All the newer machines use bushings, which is some better. Some of the smaller units used a fiber bushing, which also sucks. Then of course there's the really big units like the 3300 which has bushings, but the shafts are not big enough, so they just bend and/or break!

Kind of reminds me of all the various designs for six way dozer blades over the years, with and without lube fittings and all the varied bushing materials CAT and Deere tried.
Cheers,
Lanway

 

[darinray]

Hello Lanway,

Sure am glad to hear from you. These little buggers don't have very many sources for parts. I am wondering if you could send me some information on my unit like torque specs and diagrams. Oh of course please quote me on the duo cone and motor gaskets. I had the thing apart and soem parts ordered from dominion but later found that they are out of stock and am not sure but still haven't got the parts in. My dealers in Japan say that Morooka is out of stock on my part and may be like 2 months before they produce some more. HOLY CRAP! Anyway any and all help will be MUCH appreciated because as of yesterday my mechanic cleaned everything up and is putting it back together with no new parts yet. Talk to you soon and thanks for everything.

MST 800
Daikin Sunstrand
Model- BM21-24CTBF-50
MF21-514-50
Serial- 02-FJ-04201

Darin
email is dmm@inbox.as

 

[willie59]

LoL...hey Doctor Don! :waving


And yes, he does have good prices on brake parts.


But the meat head failed to mention he has some used/dismantled parts as well. :tong I needed a dump bed control valve not long ago for an MST-800. Over 500 bucks from Morooka, got a perfectly good used one from the doctor for half that.

 

[lantraxco]

Morooka parts

No torque specs, just use the standard torque for the fastener type and size. Morooka and Daikin are kinda like black holes as far as information are concerned, sorry.

The floating seal half is $250, in stock, the collar is $495, have to order it. I'll check on Monday and see what the lead time is if any. The motor shaft seal is $30.00, the o-ring $3.00 and the gaskets are $5.00 each for the cover gasket and motor housing gasket if you need one or both.

Meathead? Huh, I should take offense to that! LOL :Banghead

By the way, two months lead time is nothing for this stuff, when I worked at Morooka USA, it was not unusual to see six months to sometimes out over a year for some parts. Like the gears for your planetary there, they're obsolete and no longer available from Japan to the best of my knowledge. We can get complete refurbished travel motors usually, and I do wreck out some machines, but it's always hit or miss.

Cheers,
Lanway

 

[darinray]

Thank you for the info. What I am also wondering because right now she is all but mounted to be completely put back together because i thougth I was going to have to wait 2 months before the seal come in. Is there a raised seating surface on these seals and collars or is it just all flat surface mating faces? I've installed quite a few floating seals on bulldozers and these are all flat mating surfaces without a raised edge.

Morooka USA can't be that long on parts for their new stuff are they? My goodness if I paid as much for those machines new I woudl expect parts readily available. It's probably all the imported older stuff that is hard for parts yeah????

Darin

 

[willie59]

Meathead? Huh, I should take offense to that! LOL :Banghead

Naa, you won't, you enjoy me telling folks to call you for parts. :tong



Darin, the seal collar is a flat surface. The mating floating seal in the hub is just like any other floating seal, it has the angled seal surface that mates up to the seal collar surface. If both yours are flat, that simply means your floating seal is shot, time for replacement.

 

[darinray]

On my little dozer due cones both halves are basically the same size and dims. There is no collar and a seal and that is why I was a little baffled (nah alot baffled) at the design.

These floating seals are for my Komatsu D21's

 

[darinray]

have pics of the new seal and collars for these Morooka?