Bobcat CT445 starting problem

Tystix · Jun 1, 2018

Have a tractor that is driving me crazy. If you pull the fuel shut off solenoid it start fine. If you have the solenoid out and the wires hooked to it and key the ignition I can manually make the plunger retract. When the solenoid is installed this does not happen and therefor it will not start. Anyone have any ideas?

thepumpguysc · Jun 2, 2018

If its a 3 wire solenoid.. theres 2 circuits.. 1 is PULL & the other is HOLD{RUN}.. it takes ALOT MORE amps to PULL the plunger IN for starting..
& just a few amps to HOLD it..
THATS WHY you have to push the plunger in when its in your hand.. THE PULL RELAY is probably bad..
OR its just a bad solenoid.. they go bad ALL THE TIME.. & its a weak point in the system..
Good luck..

thepumpguysc · Jun 2, 2018

Just do a search on "how to test your relay".. good luck.

Tystix · Jun 3, 2018

I replaced the relay and the solenoid last year and it worked for a while now back to the same issue. I do not believe it is the relay because I can switch harness with another like relay and it does the same thing. The service manual shows how to test the solenoid and wants 18.6 ohms between 2 connectors on the harness. I'm confused at how that actually tests the solenoid?

Tystix · Jun 3, 2018

My hold wire (blk/yel) looses 12v which is approx. 2 sec. as soon as the relay clicks. I know the pull wire (blu/red) is supposed to but not the hold. This just started and has me frustrated.

thepumpguysc · Jun 4, 2018

One more thing.. the solenoid HAS TO go to the end of its travel inorder to "stick" in the run position..
They are adjustable.. I've seen TO MANY that were out of adjustment & burned-up the hold coil..
The easiest way to tell is.. remove the linkage & get it to HOLD in your hand.. now compare the angle at which it hooks back up..
& it IS possible for the hold coil to burn up IN the solenoid.. & the run be OK..
Its normal for the "hold" circuit to drop off after a few seconds.. it keeps the system from overheating the coil in the solenoid..
IF it snaps shut & then drops off.. I'd say the "run" relay is bad.. it has to switch from hold to run in a matter of seconds.. just my guess..
I'd check the "travel" first & foremost..