8 speed leak and level?

[Mike_c120 33]

Good evening! 
 

about a year ago my 8 speed started leaking from the brake shaft seal, since then I’ve replaced it 2 times and now about to do it a third. Both times I’ve used the SKF seals with metal ring on them and haven’t seen play in the shaft so I’m not sure what to do next. Also I popped off the fill port and I have fluid coming out of it like it’s full but when I pull the dipstick, it reads below the low line, wondering if anyone has had these issues maybe? 
 

Last question, is there a plate somewhere on the transaxle to see exactly what model number it is?

 

thanks,

Mike

Edited June 10, 2023 by Mike_c120

[rmaynard 14,932]

Unfortunately there is no ID on these transmissions. 8-speeds hold 2 qts of oil and the port on the side is not the fill nor the inspection area. It was for older models the only held 3 pts of oil. Wheel Horse left them on the 8-speed models and it just confuses people. Always go by the level on the dipstick and fill through the dipstick tube or the shifter hole. As far as your leak, it sounds like the seals are either bad, or somehow being damaged as they are inserted. Be sure there are no rough areas on brake shaft that could nick the seal. Inspect the shaft for excessive wear at the area where the seal rides. And lastly, be sure the seal is being inserted cup side in, flat side out. If the next seal fails, I would suspect a bad bearing allowing too much shaft movement. 

[ebinmaine 63,338]

Agreed with all above and I'd add:

When installing the seal you can wrap a layer of scotch tape around the end where there may be a groove for the locking clip and also the groove for the keyway key. 

 

That seal can be particularly stiff for some reason. 

It might help to warm the seal just before installing. 

 

 

On the fluid level and checking it,

I'd say it's time to do a complete drain and fill. 

The drain is UNDER the back of the transmission near the hitch. Likely an Allen head. 

Raise the front of the tractor as much as safely possible. 

This gets as much fluid to the rear of the transmission as you can.  

Let it set for several hours or overnight if possible.  

Check for water or any caramel/tan coloring of the oil.  

 

Replace the shifter boot if it hasn't been done recently.  

 

Refill with 2 quarts of whatever inexpensive gear oil you have. 

 

[ri702bill 7,384]

1 hour ago, rmaynard said:

or somehow being damaged as they are inserted

As mentioned, use tape over the woodruff key cut to get by that area. A bit of ATF or light oil on the seal lip and shaft helps. Once you get the seal just past the keyway cut, remove the tape - I use the brake drum without a key to square up the seal against the case - use a deep socket up against the outer hub and a soft hammer to start the seal into the bore. Remove the drum, seat the seal to depth, if needed. Then install the key and drum as usual.Try to move the shaft , using the drum, up & down and side to side without the brake band. You can USUALLY determine if there is excessive play......

 

As also mentioned, if the bearing is bad, the seal is the victim and not the real problem. The Unidrive then needs to come apart for repair. Lowell has the internal parts and case gasket.....

Bill

Edited June 10, 2023 by ri702bill

[rmaynard 14,932]

21 minutes ago, ri702bill said:

As mentioned, use tape over the woodruff key cut to get by that area.

Correct me if I'm wrong, but the shaft for 8-speeds don't have a keyway, but are a double D configuration.

[ri702bill 7,384]

19 minutes ago, rmaynard said:

Correct me if I'm wrong, but the shaft for 8-speeds don't have a keyway, but are a double D configuration.

I believe you are correct - the early 3 speeds (like the last one I did) definetely are.. The rest of what I mentioned holds true...

[OutdoorEnvy 1,447]

I’ve had good results with Napa seals and just did this same job.  Napa seal part number 7410.  I oil the shaft some and seal and slowly turn them while pushing in.  Haven’t had an issue with tearing.  A 1 inch pipe fits perfect for tapping it in to seat.  I don’t bottom the seal out.  The originals look like the they are 1/16” or so past flush so I put them about the same.  

[Maxwell-8 4,271]

A bearing failure could also result in uneven seal wear thus leaking again fast.

[oliver2-44 8,879]

Look at the shaft where the seal rides closely.  Is there a slight worn ring or depression where the old seal wore into the shaft. if there is you can try to smooth it with fine emery cloth. But some tmes you just need a replacement shaft. 

[Mike_c120 33]

On 6/10/2023 at 12:58 AM, rmaynard said:

Unfortunately there is no ID on these transmissions. 8-speeds hold 2 qts of oil and the port on the side is not the fill nor the inspection area. It was for older models the only held 3 pts of oil. Wheel Horse left them on the 8-speed models and it just confuses people. Always go by the level on the dipstick and fill through the dipstick tube or the shifter hole. As far as your leak, it sounds like the seals are either bad, or somehow being damaged as they are inserted. Be sure there are no rough areas on brake shaft that could nick the seal. Inspect the shaft for excessive wear at the area where the seal rides. And lastly, be sure the seal is being inserted cup side in, flat side out. If the next seal fails, I would suspect a bad bearing allowing too much shaft movement. 

Awesome!! Thank you for all the info I’m going to dig into this weekend and see what I can find wrong with it and why it keeps happening! You think it could be the bearing from the brake shaft itself that’s has failed also or another bearing failed causing it? 

[Mike_c120 33]

On 6/10/2023 at 1:20 AM, ebinmaine said:

Agreed with all above and I'd add:

When installing the seal you can wrap a layer of scotch tape around the end where there may be a groove for the locking clip and also the groove for the keyway key. 

 

That seal can be particularly stiff for some reason. 

It might help to warm the seal just before installing. 

 

 

On the fluid level and checking it,

I'd say it's time to do a complete drain and fill. 

The drain is UNDER the back of the transmission near the hitch. Likely an Allen head. 

Raise the front of the tractor as much as safely possible. 

This gets as much fluid to the rear of the transmission as you can.  

Let it set for several hours or overnight if possible.  

Check for water or any caramel/tan coloring of the oil.  

 

Replace the shifter boot if it hasn't been done recently.  

 

Refill with 2 quarts of whatever inexpensive gear oil you have. 

 

Thank you!! Yeah I’m going to go through it this weekend but just really wanted more input! So i appreciate it!

[Mike_c120 33]

On 6/10/2023 at 1:57 AM, ri702bill said:

As mentioned, use tape over the woodruff key cut to get by that area. A bit of ATF or light oil on the seal lip and shaft helps. Once you get the seal just past the keyway cut, remove the tape - I use the brake drum without a key to square up the seal against the case - use a deep socket up against the outer hub and a soft hammer to start the seal into the bore. Remove the drum, seat the seal to depth, if needed. Then install the key and drum as usual.Try to move the shaft , using the drum, up & down and side to side without the brake band. You can USUALLY determine if there is excessive play......

 

As also mentioned, if the bearing is bad, the seal is the victim and not the real problem. The Unidrive then needs to come apart for repair. Lowell has the internal parts and case gasket.....

Bill

Thank you! Yeah I’ll check them out because I’m leaning more to the side of complete rebuild for it! 

[Mike_c120 33]

On 6/10/2023 at 3:10 AM, OutdoorEnvy said:

I’ve had good results with Napa seals and just did this same job.  Napa seal part number 7410.  I oil the shaft some and seal and slowly turn them while pushing in.  Haven’t had an issue with tearing.  A 1 inch pipe fits perfect for tapping it in to seat.  I don’t bottom the seal out.  The originals look like the they are 1/16” or so past flush so I put them about the same.  

Yeah I like the Napa seals for sure! I’ll try the pipe next time too! Thank you!

[Mike_c120 33]

On 6/10/2023 at 1:18 PM, oliver2-44 said:

Look at the shaft where the seal rides closely.  Is there a slight worn ring or depression where the old seal wore into the shaft. if there is you can try to smooth it with fine emery cloth. But some tmes you just need a replacement shaft. 

Didn’t even think of this , I’m going to look at it this week! Thank you!!

[Mike_c120 33]

On 6/10/2023 at 9:13 AM, Maxwell-8 said:

A bearing failure could also result in uneven seal wear thus leaking again fast.

I’m going to check it out this week and make sure they’re all good. I’m leaning towards a possible bearing failure or a shaft issue! 

[rmaynard 14,932]

2 hours ago, Mike_c120 said:

I’m leaning towards a possible bearing failure or a shaft issue! 

A brake shaft bearing failure is rare because unlike an axle bearing failure, there is little pressure on the brake shaft. That said, if you do take the transmission apart, replacing that bearing won't be expensive, and it rules out one possible cause. I'm inclined to think it's the seal itself or how it's installed.