Bypass lever moves itself from drive to bypass during use

[Crunchynut]

Hi all,

I’m running ZT-3100 on an Ariens zero turn mower. The bypass levers on both sides don’t seem to lock in the drive position, so after an hour’s mowing they have rattled from ‘fully in’ (drive) to nearly at the bypass position. Only a further 5mm pull is needed to put the transmission in bypass.

Is this normal? I expected a spring or something to hold it in drive.

is the bypass progressive - meaning that, because the lever has moved then drive is being lost (akin to a clutch slipping on an IC engine), or is bypass only initiated when the lever is puller that last 5mm?

Thanks.

 

[bertsmobile1]

Most bypasses are a rod with a hole drilled through it same set up as a ball valve
So yes they are progressive but no they are not a proportional valve
On the mower case casting there is usually a detent to locate the bypass in the closed position and some sort of latching mechanism on the bar . rod , lever you pull / push / turn to keep them in the open position'Debris will build up around the bypass arm at the case which prevents the detent engaging
So start with cleaning the transmission cases , which should be done every time you use the mower
Some deck set ups are worse than others
Usually a leaf blower will work but if you have a compressor then get a really log air duster
DO NOT USE WATER