Poulan 300EX Rear End Servicable?

bjordan

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So, I have an update:

A bit of a back story first: 2 weeks ago, I used this mower for the first time and cut grass with it for a couple of hours. It ran Ok. Next morning, it was hydro locked. So, brought the mower home and ordered a carburetor for it.

While I waited for it to come in, I added fluid to the Foote/dana transaxle D6800 with 80w/90. Today, I installed the new carb, mower fired right up and ran well. However, when I put it in gear, there is zero movement (well, it did move maybe 4" once). I did not touch any belts or make any adjustments to them. All I did was remove the rubber plug from the transaxle and add fluid. The mower was cutting grass and driving fine when I shut it down 2 weeks ago. The drive belt seems to be loose to me, but not sure how much play it should have in it. There are not any strange noises coming from the transaxle or the mower. While the mower is running, I can change gears with the clutch out (not sure if that is an issue or not).

Where should I start? Belt or did I add too much fluid to the transaxle or something else entirely?

Thanks again for the help!
 

bertsmobile1

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Put the mower in the highest gear then turn the input shaft by hand ( power drill etc etc ).
You should have a manual gearbox so if the mower does not ,move when the pulley turns the shift keys in the box have sheared.
If the mower only goes forward on one wheel & seems to be trying to turn around then the brake is jambed on
If the axels turn but the wheels do not then the axel key is sheared or missing ( not all use axel keys )
 

bjordan

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Put the mower in the highest gear then turn the input shaft by hand ( power drill etc etc ).
You should have a manual gearbox so if the mower does not ,move when the pulley turns the shift keys in the box have sheared.
If the mower only goes forward on one wheel & seems to be trying to turn around then the brake is jambed on
If the axels turn but the wheels do not then the axel key is sheared or missing ( not all use axel keys )

Thanks Bertsmobile1.

Here is what I found. With the rear end jacked up, when I spin a wheel, both shafts turn in opposite directions, as they should. I started the mower and with the rear end jacked up off the ground, the wheels spin fine. When I lowered the mower, no movement. With the mower on the ground, I also hear a very slight whine, coming from in front of the transaxle. Sounds like the drive belt may be slipping. I know this belt is an older belt, how old, I do not know.

Are you thinking its the drive belt? Is there some kind of slack adjustment that can be made to make the belt tighter?

Thanks in advance for all the help!
 

bjordan

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Re: Poulan 300EX Rear End Servicable? UPDATE 4/9

Mower still wont move.

Here is the latest: I replaced the drive belt with a new belt. I also replaced both idler pulleys (Flat and V-belt pulleys). With the rear end jacked up, the wheels drive fine. When the wheels are on the ground, nothing.

I may have overfilled the transaxle with 80w/90 gear oil a few weeks ago, so with the help of a friend, I tipped the mower to the side and removed some of the fluid.

I am at a loss as to what to try next. Any ideas?

Thanks a million for the help!
 

bertsmobile1

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Check to see if the axels are turning but the wheels are not
There is a shear key in the rear axels and if one is broken or is missing you won't go anywhere.
 

bjordan

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Check to see if the axels are turning but the wheels are not
There is a shear key in the rear axels and if one is broken or is missing you won't go anywhere.

Thanks Bertsmobile1.

The shear key is on the rear axle, between the wheel hub and the axle. When the back end of the mower is off the ground, the wheels turn, but I can stop them with my hand.
 

bertsmobile1

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Thanks Bertsmobile1.

The shear key is on the rear axle, between the wheel hub and the axle. When the back end of the mower is off the ground, the wheels turn, but I can stop them with my hand.

A bit hard without having the unit here in the shop but it is sounding like a broken shift key in the box itself.
Mower boxes are constant mech, which means every pair of gears are turning against each other all the time,
On the input shaft the gears are all fixed
On the output shaft there is a slot with a sliding key that fits into a keyway cut on the inside of the gears so only one output gear can drive the output shaft at any one time.
Changing gears while moving breaks off the head on the key so you get a light sort of drive when there is no load from the remains of the key and viscious drag from the grease.

After that the axels themselves can have a gear with a key on the other end.

We don't get that mower here so any more & I would be shooting in the dark.
All mower gearboxes ( not hydros ) work the same way so if you download the Tecumseh / peerless service manual you will get all of the information you need to pull your box apart.
 

bjordan

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A bit hard without having the unit here in the shop but it is sounding like a broken shift key in the box itself.
Mower boxes are constant mech, which means every pair of gears are turning against each other all the time,
On the input shaft the gears are all fixed
On the output shaft there is a slot with a sliding key that fits into a keyway cut on the inside of the gears so only one output gear can drive the output shaft at any one time.
Changing gears while moving breaks off the head on the key so you get a light sort of drive when there is no load from the remains of the key and viscious drag from the grease.

After that the axels themselves can have a gear with a key on the other end.

We don't get that mower here so any more & I would be shooting in the dark.
All mower gearboxes ( not hydros ) work the same way so if you download the Tecumseh / peerless service manual you will get all of the information you need to pull your box apart.

Thanks Bertsmobile1! I guess I will be taking the transaxle off and opening it up in the next few days. I will let the group know what I find.
 

bertsmobile1

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Just to make sure.
Can you push the mower with both wheels on the ground.
If you can push it then the problem is in the box
If you can not push it which both wheels on the ground then the brake is still on & locking the diff.
With the wheels off the ground and you turn one, the other should move in the opposite direction but when being driven by the engine they both should turn in the same direction.
If they turn opposite direction then the brake is still locking the diff.
The brake on mowers works the same as the P position on your cars tranny
It locks the diff so the wheels can only turn in opposite directions so the vehicle can not move in either direction.
 

bertsmobile1

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I never answer technical PM's as it subverts the whole idea of an open public forum
So this should be the schmatic of your box

View attachment Poulan 300EX.pdf
The shift keys are the parts marked 8.
The shaft # 67 has 2 slots in it and the keys slide along it to select the gears.
Note the gears marked # 83, # 49 , # 50 etc have slots in them for the keys to fit in and lock that gear to the shaft.

Also note near the bottom, the brake rotor # 36 which is fixed to the layshaft # 4
If that rotor is not turning then the brake is locked which locks the diff as mentioned in the previous post.
 
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