tz25 da wont start

[craigsurf]

i have a dead tz.
all started fine as usual when i moved the tz out of shed .
would have been running for around 5 minutes . i shut it down and when i returned in the afternoon it would not start as the glow plug light failed .
starter was still operating at this stage .
next day i returned to see if it had miraculously reset itself and turned the key to start and this time there was no starter as well .
i have replaced fuses and have put test light on them and they seem fine .
all lights and fuel pump are still operating with ignition on.
i disconnected the wire to the fuel shut off soleniod and no voltage here .
i did run direct from batt positive to fuel shut off soleniod and it clicks in & out with current .
have bridged seat switch with no result .
the tz did not fail when it was operating , it just developed this problem after i shut it down and returned to use in afternoon.
i have now stripped it down to the chassis chasing this gremlin.
have not yet looked at ignition switch.
tz has 350hrs clocked up and is 2005 model.
park brake alarm does not work and i have not suspected this as the problem as it has worked intermittently for 2 -3 years now.
i also have power at the glow plug buss bar
any suggestions out there from experience where i should target problem

thanks

 

[dave1949]

Jinman (Jim) always recommends checking the in-line fuse in the + cable. It should be somewhere close to the battery. I think it is molded in, so you don't realize it is there.

 

[jinman]

Dave, if he has lights, it's not that main fuse. It sounds like a loose or broken wire in the neutral safety switch or PTO safety switch. Of course, it could also be the ignition switch. The best way to check that is to pull a fuse and put a meter from the hot side to ground and turn on the ignition switch. If it has power, the switch is working. The neutral sensing switch has been a problem on lots of tractors. It's best to wiggle the lever around neutral while trying to start the engine.

 

[dave1949]

Duh. I missed the lights working. I was thinking that the negative battery connection should be okay if jumping to the solenoid made it click, then my mind wandered off across the battery, or somewhere.

 

[craigsurf]

Duh. I missed the lights working. I was thinking that the negative battery connection should be okay if jumping to the solenoid made it click, then my mind wandered off across the battery, or somewhere.

thanks chaps for the reply .
i have done the wiggle test on the transmission lever with no result .
however the pto light on instrument panel does not work when i engage the pto lever.
i have not used the pto on this machine since i purchased it as i only use the 3 point and front loader

 

[craigsurf]

neutral sensing switch sounds like a possible culprit Jim

any idea where i can locate this

 

[craigsurf]

neutral sensing switch sounds like a possible culprit Jim

any idea where i can locate this

 

[jinman]

Look at the locator diagram # 28/29 and the switch photo with part number. That switch screws into the side of the transmission and senses the transmission in neutral range. It has two wires with push connectors that are easily disconnected. If it is defective or the wires loose/broken, it will give the exact symptoms you are describing.

 

[craigsurf]

Thanks jim
I have checked pretty well all safety switches and all are working
I have disconnected these and found voltage as well as run a test light and all good.
I went back tonight and switched the ignition on and the pto light and glow plug light returned
Yet no crank power .
I have 12plus volts at starter motor with ignition on .
Then the glow plug and pto lights failed then came back a couple of times intermittently .
I noticed slight corrosion on a couple of terminals of safety control unit and have back probed with voltage there but still remain a little sus about this .
Not sure if ignition switch can give intermittent symptoms as this .
Will check again tomorow and if I get the glow plug and pto lights back I will leave ignition on and wiggle test everything as this thing is playing games with me.

 

[craigsurf]

well i have done the wiggle test with ignition on and glow plug light on and no drop out .
but after i turned off ignition and back on a couple of time s i lost the glow plug light and pto light again .
so does this warrant more inspection of ignition switch or should i look elsewhere

 

[jinman]

I'm not sure why your PTO light is coming on. Do you have the PTO engaged? I'm also not completely familiar with your TZ25DA, but I would check power to the headlights when the glow plugs quit working. If the headlights work, then you probably have a loose wire or the glow plug timer may be timed out or bad. For sure, if the PTO light is on, the tractor will not start. You may well have a safety module issue, but I'd need a schematic and hands-on troubleshooting to prove that. I am not going to suggest that you replace it if you are not sure it is bad. It just costs too much to "Easter Egg." It does sound like you have a faulty glow plug timer, but they are not cheap either at around $70 each. I'd suggest a cheaper alternative on eBay, but your being in N.S.W. is gonna put a hitch in that solution.

You mentioned jumpering the fuel solenoid to get it energized. You can also hot wire your starter to get it to operate by using a jumper between the large connector where the lead comes from the battery and the small connector to the solenoid. By touching a jumper, the starter should engage and turn over. If it does not, then you have a bad starter or dirty battery terminals; maybe a loose ground wire connection to the chassis from the battery cable. If the fuel solenoid is jumpered and you engage the starter, the engine will start whether it is in gear and even with the ignition turned off. Once the engine starts, the only way to stop it is pull the wire to the fuel solenoid. Just remember, if you do this, you are bypassing all safety features. It's an emergency way to get a tractor moved or onto a trailer, but not good practice to operate in such an unsafe mode. By all means, make it temporary. This will just tell you if the battery connections are all good and if the starter will function properly.

 

[craigsurf]

Reason for PTO light was to engage to test if safety switch working so will take this out of equation from here on Jim.
have not lost any power to headlights or instrument panel .
If glow plug light mysteriously appears again as it has the last couple of evenings i will hold to see if it times out .

What i need to do is to systematically run through the electrical testing and indicate on the wiring schematics where and when i have power as
i have been doing mostly yet i have been jumping around a bit with this causing more testing . However i need to record this on the wiring diagram each step and then send diagram to you.

Hopefully this will better assist in putting yourself or someone in the picture as to where i can target problem

Thanks

Craig