B3350 won't start - safety switches?

[retiree-urgency abandoned]

Was moving logs from storm damage when I turned off the machine to do some chainsawing. When I tried to start, it wouldn't. Lights on panel come on and glow plug light/click comes on. My suspicion is that one of the plunger safety switches is open - either the neutral pedal switch or the pto on/off switch - these would prevent the machine from starting.

Of course, I've got the belly mower on and am parked in the field. I tried jumping the starter solenoid, but couldn't reach it. There's no way I can reach the neutral switch and things probably wouldn't go well if I tried to dissemble the seat to get to the pto on/off switch. At this point, I've resigned myself to wait for my dealer to pick it up and fix it (they're 3 weeks out to get to me). But that doesn't stop me from being "annoyed" that but for a 1 or 2 cheap switches, I could be doing the chores & projects I need to be doing.

Given my age and decreasing dexterity, I'm considering the possibility of an emergency bypass switch for these 2 switches. Looking at the schematic (it's for the cab version - mine is ROPS), when the key is turned to ACC or further it looks like the closed switches deliver 12v "signal" to the ECU. I've marked the ACC supply line with green - from what I can tell, it's an L/R wire (would that be lavender/red?). It looks like I could tap in past the safety switches (under the dash before the lines hit the ECU - marked in orange) and use a DPST switch to connect from the supply (marked in purple) to the orange taps. I need an old-geezer-friendly way to temporarily jumper these when they fail, but I'm not so far gone to forget to turn the pto off and put the machine in neutral when I turn it off.

Would welcome input/thoughts.

 

[Jim L.]

Sorry that you're having this problem.

I don't think that posting how to override safety devices in an open forum is wise.

Some of these switches have both +12VDC and ground separate circuits. Mixing those with an ECU could be pretty dicey. Look at the price on an ECU -and- the cost to install it. Very easy to go from bad to worse.

L/R would be a blue with a red stripe.

 

[GreensvilleJay]

simple test... if you can get to the starter, with key on, jump big +12 to the little 'stud', see if starter spins.
Can't tell by your posted picture as 'starter's cut off the bottom'. Usually the 'starter relay' is just a control relay that sends power to the 'real' starter relay, inside the starter'....
it's a shame the 'engineers' have to make a simple tractor COMPLICATED. Obviously they've never worked on a farm or had to troubleshoot what they 'designed' when it breaks down in the field with 50 cows hollering 'where's my dinner' !!!

 

[retiree-urgency abandoned]

Jim L. - I'm definitely not one to ignore safety. It's just extremely frustrating having to leave it parked outside in the field for 3 weeks, since I always keep it in the barn. As far as the temporary bypass switch, it could be a spring-loaded momentary on switch, so there be no chance of accidentally leaving it in bypass mode and you'd definitely know to turn the pto to the off position and put the range in neutral before doing a bypass.

GV Jay - You're right - it always happens at the least convenient time and as far as possible from the barn and concrete floor. I don't have another machine to tow/push it back under cover.

With difficulty and some contortions I was able to reach the starter well enough to get a screwdriver across the terminals and get it to spin. It just didn't engage and start the engine. I ran the glow plugs for the normal amount of time and then left the ignition switch at on before jumping the terminals. Is there another step I'd need to do to get it to engage & start the engine or am I just SOL?

 

[Russell King]

You need to connect power to the spade (red must be shorted to blue in photo below). If you can get the wire off the spade connector and then connect a long wire to the spade terminal, touch that to battery positive and tractor should crank. If key is in run position then it would start. If you are not careful, then tractor could kill you by running you over!

So be careful!

If the starter just spins and the bendix doesn’t engage the flywheel then you need a new solenoid or starter assembly.

 

[retiree-urgency abandoned]

Thanks Russell - that's exactly what I was looking for. Access was tight when I jumpered the big terminals the other day and visibility was challenging - even with a flashlight due to the sunshine. Weather permitting, I'll give it a try tomorrow. If I can get to that terminal, I may just run the wire to near the seat. Since it's not going to draw much current, I'll touch it to the hot contact on the outlet by the seat - probably a safer place to be when trying this maneuver.

 

[North Idaho Wolfman]

You better be very careful in what actions you take.
One misstep and you very likely to have an egg plant for a tractor.
The ECU in that tractor is very finicky to begin with and jumping things like the starter can have some serious repercussions.
If you short out the ECU it's going to set you back about $4k.

If it won't crank and you jump it, it's not necessarily going to start and run.

I would start by checking all the fuses and moving all the levers and the HST pedal.

 

[retiree-urgency abandoned]

SUCCESS!!

Before moving forward, I called my dealer to make sure that this wouldn't fry the ECM and he confirmed that it wouldn't - thanks to NI Wolfman for the caution. Temporary battery to solenoid terminal jumpstart worked. With a little more patience and a lot less sun, this time I removed the heat shield (2 bolts - orange arrows in photo) and had a lot better access. i was able to easily remove the harness connector from the solenoid terminal. I crimped a connector onto my green jumping wire and threaded it to the battery. First I tried activating it from the accessory socket by the seat, but not enough juice, so this is a hood-open touch-the-battery process. Photos show various steps as well as safety reminder on the dash.

Feels like a cross between Hilljack Motor Specialties and the Flintstones, but it got me started and into the barn.

Thanks to all for your help with this!

 

[S-G-R]

Glad you got it to the barn. Let us know the outcome of what the issue is.