Bobcat 331 2speed function

[304Bobcat]

I purchased a 1999 Bobcat 331 serial 512918539 few months back and I am in the process of getting everything back to working order. I installed two new final drives, new 2speed solenoid, and new foot switch. After installation nothing happens when foot switch is pushed while track is traveling in either direction.

So I did a little testing and I have 12v power (hot and ground) coming into the foot switch. I have 12v power coming into the solenoid if I push and hold the foot switch. So the foot switch doesnt switch power on and off but only connects power to the solenoid while pushed in only, once released power is cut to the solenoid.

My question then is..... is the solenoid a pulse style solenoid which just takes a brief pulse of energy to move and hold the valve open or closed in the Accumulator? Im trying to understand how the solenoid and valve work. Obviously the solenoid doesnt get constant 12v power like I would have thought in order to energize the magnet and pull up the valve stem. So does anyone how this solenoid valve works? It seems to me nothing is happening with the valve in the accumulator when power is sent to the solenoid.

 

[304Bobcat]

Ok I was wrong. The foot pedal actuator must be held down the whole time to energize the 2 speed solenoid which should open the valve allowing fluid to flow from the solenoid to the control valve servo on the boost section of the 5 spool valve. Fluid flows from B port of the boost valve through the check valves to the left and right travel valve sections for increased flow from the main 3 section pump. Now we are getting somewhere, although the....have to hold your foot on the actuator the whole time is not ideal to say the least and had I known I wouldnt have bought it and just wired the solenoid to a switch mounted on the console. Which I still may do anyways. So at this point Im guessing there is a certain amount of fluid pressure needed to work the valve and engage the two speed? If the solenoid is working correctly when actuator is pressed and held down what could be the next reason the 2 speed isnt engaging? Not enough pressure from the pump? Main relief valve pressure set to low? These are two new final drive motors and 2 speed valve blocks installed and I cant seem to get the 2 speed to engage.

 

[304Bobcat]

All is well. I got the 2 speed working like new again. The spring loaded inner sleeve on the accumulator 2 speed valve stem was stuck probably due to the solenoid going bad and the sleeve in the valve stem never moving so it probably just over time stuck in the normal "closed" position. Fixed now

 

[Vetech63]

This forum will close up if this keeps happening lol