Small Engines (Lawn Mowers, etc.): Intek Pro 65 OHV B&S Ride on mower not pulling cleanly


Question
Small Engines (Lawn Mowers, etc.): Intek Pro 65 OHV B&S Ride on mower not pulling cleanly
Intek pro 65 ohv Ride  
QUESTION: Dear Mr. Jones,

I have an Intek Pro 65 OHV Briggs & Stratton Ride-on mower. (pic included)


My problem:
The mower does not pull "cleanly" in any gear.  It "jerks";  it accelerates-jerks-accelerates-jerks; as if you are advancing the throttle then ease off the whole time (but the throttle remains in the same position),  but when it idles or rev's, the engine runs smoothly (in Neutral position).


My question:
Could it be due to a worn belt, or possibly, something wrong with the gearbox?


What I have done so far:
*I gave the engine a service (spark plug, air filter + pre filter, new oil).  The engine starts easily, idles smooth and rev's beautifully.

*I have adjusted the belt so it's firmer by adjusting the tensioner.  It is quite taut now and somewhat hot after a few minutes of riding.  

*I removed the rear wheels to see if the keys and key-ways which drive the mower are still intact, they seem fine.



Thank you kindly in advance for any suggestions/help.

ANSWER: Can you describe the drive system?  It is a friction disc drive system like Snapper mowers use or does it have a gearbox and rear axle?

I've seen some similar mower designs but nothing exactly like yours.

Let me know about the drive system.

Eric

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Small Engines (Lawn Mowers, etc.): Intek Pro 65 OHV B&S Ride on mower not pulling cleanly
Underside of mower  
QUESTION: Thank you for the speedy reply Mr. Jones,

I have found that the chassis of this specific type of mower is generic and thus was branded under different names ex:

*Castel Lawnking AT63 Ride on Lawnmower 24in Cut
*Garden Compact E Stiga
*Mountfield 725 M Ride On Lawnmower

On the seller's pages there were 2 descriptions given for the transmission namely ,
1.) Transmission variable forward and reverse,
2.) Gear and differential 3 + R

My mower has a gearbox which ultimately drives the rear axle by way of keyways and keys in the wheels and on the axle.

I  found an image of one of the models which might be helpful

ANSWER: The transaxle in the picture is very similar looking to Tecumseh/Peerless or Dana/Foote/Spicer units.  It's likely one of these companies made your transaxle.

The description says variable...can you tell me if you have 1 drive belt or 2 drive belts for the traction drive?  

Do NOT count the blade belt...the blade belt should not be part of the traction drive system.

Thanks.

Eric

---------- FOLLOW-UP ----------

Small Engines (Lawn Mowers, etc.): Intek Pro 65 OHV B&S Ride on mower not pulling cleanly
Single belt driven  
QUESTION: Dear Mr. Jones,

I can see only one belt linking the engine and the gearbox.

(see image)

Answer
Thanks for the picture.  The fins on the transaxle case are interesting...something I have not seen on Peerless or Foote/Spicer units we have in the US.

Are there any manufacturing numbers or a brand name on the transaxle.  Often times there is a sticker, raised letters, or a metal tag on the transaxle with the manufacturer's name along with the transaxle model number.

You may have a hydrostatic transaxle.  Are there multiple forward gears where you have to manually shift or change gears for different speeds?

Eric