Craftsman deck adjustment question

[doitmyself99]

Does anyone know if the the front/back leveling adjustment has any impact on the deck belt tension? On an older Craftsman 42 inch mower - new pulleys installed all the way around along with new belts, deck adjusted to almost level, now the blades wont spin at the correct RPM as if the belts are slipping. The mower does not provide any belt tensioning capabilities. The only deck adjustments are left/right and front to back. Will lowering the front by extending the control arms push the deck to the back and put more tension on the belt?

ANY help is greatly appreciated.

 

[rekees4300]

"The mower does not provide any belt tensioning capabilities."

On my Craftsman the tension can be adjusted by rotating the rod between the manual mower engagement lever and the deck. But your mower may be different? Check the owners manual. If you don't have a manual then they can be obtained from Sears.

Another possibility is that you installed the new belts inside out.

 

[alchemysa]

Don't know about your Craftsman, but on a ride-on I saw recently the belt could be tensioned or loosened slightly by moving the connecting rod to a different hole at the bottom of the lever/handle. It was difficult to see without removing a cover plate.

My own Viking ride-on mower can be adjusted by moving the spring tensioner to a different hole in the lever, however I have found that this still does not provide sufficient tension so I have had to 'wire up' half the spring so that it cannot stretch too easily. So far this fix is working nicely and is providing the right tension. Its a fine line between too loose and too tight. (A too tight belt won't let the blades come to a rest when they are disengaged - or the belt can burn because its resting too tightly against the engine pulley.)

Of course you need to be sure that someone hasnt 'upsized' the belt sometime over the last 20 years - meaning that it may be an inch or two too big for the mower.

 

[bp fick]

Manuals, parts, operator manual, etc can all be downloaded in .pdf file from Sears Parts Direct. Not a problem. Once you have that manual downloaded and studied, you should be able to determine rather quickly if the belt is the wrong belt, on backwards, or if a tension issue is in play.

I downloaded the manual for our DYT4000 and have ordered parts. It's pretty darn good!!!

 

[doitmyself99]

It ends up that the deck is raised / lowered via bars that hang on a fulcrum that is controlled by the deck height lever. The bars attach to frame on one end and the deck on the other. The mounting point on the frame is adjustable up and down.

My mistake was thinking that lowering the brackets in the front (which I had done) would force the deck further backwards when lowered (putting tension on the belt) which in fact was the opposite of what happens. By lowering the mounting points, it cause the back mounting points to shift upwards as the front and back move in opposite direction around the fulcrum point... This in effect put less tension on the belt not more! Once I raised the front mount point brackets upwards, things started working as designed.

Learn and live...

Thanks for the suggestions