L4600 wont stay at thottle

[ENC]

First post and i have a problem. Have a L4600 HST. I bought it new and have about 20 hours on the meter so i could probably use my warranty but i thought it might be a simple fix that i am not seeing. This just started today. The throttle lever will not stay where i set it if i move it over about 1800 RPMs. As soon as i let go of the lever it idles back down under spring pressure from somewhere on the lever or linkage. Any help or advice is much appreciated. Also please excuse any typos or punctuation errors as I usually only post from a phone.

Evan

 

[pedalstomper78]

Most hand throttles still have a safety spring on the injector pump in case the cable breaks etc, the engine doesn't stay humming. In most cases, your hand throttle uses a lock nut and a nylon washer on the lever that goes in your hand. Get to the base of that, give it 1/8 of a turn and test. See what feels right. It should move fairly easily, but not drop down like your current problem.

 

[Chilly807]

What PS78 said is correct. If it's similar to the L3400 I have, there is a clamp arrangement on the vertical part of the throttle shaft that has 2 nuts. You loosen the outer nut, set the tension with the inner one, then re-lock the outer one to hold it in place. You'll need a thin 13mm open end wrench if I remember correctly. Mine was set too tight for my liking, I loosened it slightly and it's fine now.

Sean

 

[ENC]

I didnt get home before dark today to try it out, but is it normal to loosen up suddenly like it did. One day it was fine the next it wont stay throttled up?

Thanks again hopefully i get it fixed tomorrow.

 

[pedalstomper78]

If the nuts turn, each time you pull/push on the throttle, they will move with it. Sounds like you and Chilly will have a 2 nut setup with one as a lock nut. My tractor uses a nylock nut. Either way, a simple and cheap fix for ya. Can't beat that.

 

[ENC]

Thanks got it fixed. The lever is definetly stiffer but will hold it in position. It was a 12mm wrench. Thanks again for the help.