small fuses and electrical weirdness on 7610s

[Soundguy]

Had a bunch of work to get done on the farm yesterday, including knocking down some briar that has been taking advantage of the warm florida winter. After mowing for a couple hours iwas heading back tot he barn, and noticed i didn't have my headlamps on.. though did have the flashers. I like to drive with headlamps and flashers if I have to cross over a public road.... Turnign ont he headlamps immediatly killed the tractor. Lucky enough i was at little more than idle, and on a road with no real traffic, and no curb. Tractor started right back up fine.. had me puzzled for a minute... I didn't equate the lamp switch with the stall... ( lamps did come on.. but I shut them down whent he tractor powered off ). Fuel was good.. new fitler... Started back up.. then I made the connection between the headlamp and stalling. Also noticed that many dash lamps did not power when turning key from off to run to start.. etc.

Got home ok, started digging around under the hood.. jiggling wires.. tested alternator output... No loose wires on lamp switch, no loose wires at key switch... alternator putting out ok.. Then remembered reading some weirdness about fuses blowing on NH tractors.

Well.. my battery had been low from setting as the tractor hasn't had to work since october.. so I had to jump her from my truck.. first attempt befor ethe jump yeilded a couple turnovers and a click..click..

The only fuse panel I can find ( universal XX10 owners manual is little help on the wireing and fuses! ) is near a relay pack under the hood. Sure enough there was a 7.5a fuse blown. Put in another and tried some tests... everything worked ok for a little while then it popped again. Added alarger fuse and is now working. Never did find what that fuse was for.. but has got to do with dash and fuel pump cutout.

I'm glad the lamps and everything are back to 'playing nice together' as they should be.

Was getting cool and dark so I greased and re-fueled the tractor and got her parked and then went off to tnd the horses.

Any ideas on that fuse issue? I guesss the hard start blew it...

Soundguy

 

[jinman]

Chris, it sounds like you may have dirty battery terminals too. On my tractor when the battery is low or not able to supply full voltage, that seems to be when the fuse blows. If you loaded your electrics by turning on the lights and it caused so much load the fuel cutoff solenoid dropped out, I'd be suspect of the battery terminals. In some wiring schemes, the power from the alternator is tapped at the battery instead of the solenoid; therefore, corrosion can also cause poor contact from the alternator. I'd think in Florida's humid environment a cleaning of the terminals is something you'd have to do much more often than here in our 20% humidity.

 

[Soundguy]

Hmm.. could be.. but I doubt it. Terminals are clean. Battery is new as of 1 year ago, with nicely greased contacts. Charges ok, I tested that /forums/images/graemlins/grin.gif As it stalled on me a couple times away from the barn, it started up good both times.. so I know the alternator is charging, cause it was near dead when i went out in the morning, and just 2 hours later had plenty of juice to crank the tractor over.

It's just plain weird... no loose wires ( that I could find ).. I even check the wires on the injector pump.. pulled each one and reseated.. ( maybee one had been loose?? and now is 'fixed' )? Is the fuel pump solenoid a 'normally closed' product and then opens with key/ignition power? if so.. that may have been it.. a loose wire on the solenoid, coulped with the blown mystery 7.5a fuse?

I wish the manual had a wire diagram /forums/images/graemlins/crazy.gif.. or fuse listing even... I have no idea what fuse I repalced....At least it is working now...

Soundguy

 

[RickB]

I agree with the low voltage/poor connection diagnosis. If you are confident of the battery connections, check the starter end of the pos cable and the chassis end of the ground. If the starter has a dedicated ground lug at the front of the starter, move the ground to a cleaned starter mount bolt. The dedicated grounds are noted for internal opens. Remember, low voltage=high amp draw for a given function. The key indicator is an unrelated fuse failure when the headlights were turned on.