Keith True

Well-known Member
I have a 751 Bobcat skidsteer that the fuel solenoid is not getting energized.fuse is OK,swapped the relay for a working one,but nothing seems to be getting to the solenoid.My 751 book is for a little earlier machine,with no computer.This machine is one of the first of it's series to have one.The engine itself is not computerized,just the outside controls.I don't seem to get any juice to the harness connection.But,when I unplug the harness from the solenoid I get one beep from the alarm.So,I would say that the solenoid must have a ground in it that is talking back to the computer.I do have another machine,no computer,but same solenoid,so I swapped it into the non runner.No difference.I'm leaning toward a computer problem.Anything they are noted for doing? All other computer controlled functions are fine.
 
How many wires on the solenoid,has the machine an immobilizer fitted,if so what type?
AJ
 
It has the 3 wire solenoid.Same solenoid,same part number as the one on my 753.I guess I don't know what the immobilizer is on that machine.I don't have a manual for this serial number machine yet,mine is for the earlier series without the computer.
 
Does the 753 runs with the 751 solenoid?. I think the three wire solenoid has a ground and two power wires,there is no power in the wires when the key is on if my memory is right,when the key is turned to start power is sent in one wire to energize the solenoid which jumps to the run position,when the engine starts wire #2 takes over and holds the plunger of the solenoid in the run position,if you had the cab up one of the many safety switches may not be closing properly check em all,I am not familiar with skid steers but know the engine from mini diggers,welders & compressors etc,have a look at the safety switches and see what you find.
AJ
 
The 751 solenoid is bad,it doesn't work by putting it on the good operating machine..I put the 753 solenoid on,it won't work on the 751 either.It does work on the 753.Same part number on it.What I'm wondering is,did the solenoid go bad and fry something else,or did something go bad and fry the solenoid.I understand the two coil setup,the high draw to pull it in,and the low draw to hold it there while running.It is supposed to snap open when the key is on.My 753 does that,and my 331 does it too.They all use the same engine.Both my other machines use simple relays,but this newer one is told what to do through the computer.One thing to add,he said for a while now the solenoid wouldn't always kick in with that loud snap when he turned the key on.He had to poke it with his finger,and it would jump into position.That turned out to be the heim joint was sticking.
 
I looked on line for a manual for the 751 and found one to download free but it's no good for your machine as it is showing that it's fitted with a Peugeot/Citeron engine with a rotary pump,the wiring on the Bobcat's differs from the other applications that the engine goes in as the plug is dead till start is engaged,if the key on energizes the high draw coil it must have another way of releasing it when the engine starts as the key stays in the on position,when you said alarm are you referring to the warning buzzer or has the machine a tracker like device fitted that you need a magnetic key for,Iv'e have loads of trouble with that type system, with a known good solenoid have a look at the key switch I had some that the bottom come out of the housing just a fraction and they would not make contact.
Good luck
AJ
 
On my 753 skidsteer and my 331 excavator the fuel solenoid kicks in when the key is turned on.It makes a real loud snap,I always listen for it because in real cold weather if I don't hear it I don't even bother turning the engine over until I open the door and push it with my finger.I do know of a generator with the same engine that powers the solenoid up when the switch is turned to the start position,as you've described.I'm going to give it another look when I get to the shop,where this is a later machine with computerized electrics it may just be activated differently than my older machines.While I found the solenoid was bad,when I put my known good one on to try it I only turned the key on to try it.I didn't try to crank it over,It will take me less than 5 minutes to put my good solenoid on and try cranking it.I can see them changing it over to that design when they went to a computer,they really want as little current as possible running through the computer.
 
I cannot speak for the Bobcat,a lot of machines have a battery cut out switch on the ground cable its a fairly beefy solenoid that makes a loud click when switched on,even if yours does switch on with the key it would have been that way from the factory and should not be an issue now,have another look give the plug to the computer bit of a jiggle and come back.
AJ
 
Well thank you very much,you sent me in the right direction on this one.This computer controlled machine activates the solenoid exactly like you described,activated when the switch is turned to start.The older machine activates the solenoid by just the on position.On top of that I looked at my friends generator with the same engine,and he told me that one doesn't activate the solenoid by the start position like I thought,it activates when the oil pressure comes up while cranking.I do know the solenoid was bad,I just borrowed the one of my other machine for the day.
 

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