TimberJack 350 with Clark 3 speed power shift problems

CougarChris · September 27, 2020, 02:31:56 PM

Hi hello,, new to the site and looking forward to seeing who is out there in this big world,,! I've had this TimberJack 350 for a couple years now,, she has a new motor that just hit 500 hours,, she has been a great machine to me,, recently when she is cold she dose not want to get up and go like she used too,, starts up wam bam but takes a bit to get rolling after being put into any gear,, once I rev er up a bit and get the tires rolling she is super solid all day long no questions asked,, even once she is warmed up at any point in the day and I start er she will go into any gear and go but this cold start thing has me worried,,, once hot and going tho she pulls a mean load,, I'd like to think that a a new filter and maybe fresh atf in er will fix this problem,, any suggestions,,? Thanks

mike_belben · September 27, 2020, 02:56:01 PM

The 3 speed powershift in my forktruck is about the same.. You can hear the tone change when "it" wakes up and unglues its heavy feet from the spot its been parked.

I imagine its crossleakage in some control valving section that is "hanging" two planetary gears until things warm, swell and seal up so to speak then the offender stops getting slightly pressurized.

In automotive trannies i have solved this by flattening the valve body mating surfaces on sandpaper that i "glue" to a piece of glass by soaking the paper in diesel fuel to wetsand. The manufacturers just flycut these things as fast as they can and never lap em in. When you make your first few passes you can see the cutter streaks and ridges. A metal separator plate gasket is not good at confirming to a rough RA surface at all.. Thats what cork gasket was for. Any metal gasket wants a zero surface roughness. Perfect flatness for metal to metal sealing. Otherwise fluid pressure goes where it shouldnt.