Bobcat 743B won't start

[bludev]

All, It was cold yesterday when I attempted to start my 743b ('92, 3000 hours). When I first tried it, it turned over and even started and ran rough for about 5 secs before stopping. But then the battery got weak and wouldn't turn it over. I then tried jumping it from my truck ... it turned over some (although very slowly) but never ran. I disconnected the jumper cables and used a battery charger in "start-boost" mode. Now, nothing happens. I measure the voltage on the battery and was getting 12-13 volts. I noticed then that when I would turn the started key to the left (to warm the glowplugs)I could hear a faint click like a relay kicking in and then another faint click like the relay letting go. And when I turned the key to the right when I normally hear a distinct click, nothing happened (completely silent) ... needless to say, the engine never turned over. Isn't there a relay (or two) in the starter circuitry ... could that have gone bad ? If anyone can help, I would appreciate it (my cows are getting hungry). Thanks, Roger

 

[skidsteer.ca]

I then tried jumping it from my truck ... it turned over some (although very slowly) but never ran. I disconnected the jumper cables and used a battery charger in "start-boost" mode. Now, nothing happens. I measure the voltage on the battery and was getting 12-13 volts. I noticed then that when I would turn the started key to the left (to warm the glowplugs)I could hear a faint click like a relay kicking in and then another faint click like the relay letting go. And when I turned the key to the right when I normally hear a distinct click, nothing happened (completely silent) ... needless to say, the engine never turned over. Isn't there a relay (or two) in the starter circuitry ... could that have gone bad ? If anyone can help, I would appreciate it (my cows are getting hungry). Thanks, Roger

Did you check voltage while glow plugs were on or while cranking. My guess is your voltake through thejumber cables and battery charger is too low
while cranking.
The only relay I'm aware of on a743 is the starter solinoid.
Ken