Oil & Fuel MF 135 battery not charging, what to do?

[pmsmechanic]

If the tractor was running when you put the screwdriver to the rear bearing you should feel some magnetism if the alternator is charging.

If you can charge the battery with a battery charger and several days after removing the charger it still starts the tractor then there is nothing wrong with the battery.

 

[SIMassey]

Looks like an alternator

Seems to me that I remember reading here that there is a switch or relay triggered by the oil pressure that controls the charging of the battery. The theory being, since there is no ignition switch on the tractor, (only a start switch) the alternator needs an exciter wire to make it charge. If the wire is hooked solid, it would run down the battery when engine is off. When oil pressure triggers switch, battery charges. Maybe someone has a wiring diagram for a diesel that can verify this. It is supposed to be under the dash by the oil pressure gage.

 

[Soundguy]

Could be.

Or they could just use a common b circuit regulator like many alts used, and bootstrap the alt to charging with close field contacts at startup, and then a cutout that pulls in after startup.

 

[jrmcdona]

Found a wiring diagram in this thread.
http://www.tractorbynet.com/forums/...intage/169437-massey-ferguson-135-wiring.html

 

[TomSeller]

. This one has 1880 hours but I think it was kept outside some and could use some clean up. Definitely not the super mint MF 135 but was a good deal, or at least I thought it was at $3,000.

At 1880 hours, a Perkins Diesel in a MF135 for only $3,000, you got a steal of a deal if the engine was well cared for. 1880 isn't even broken in. With your dry flat land in the pictures, 2WD will do well. Nice find. Rubber looks good, paint looks good. Nice to see the old iron appreciated. You could have easily spent 10x that on a new tractor that at the end of the day does no more. Good job!

 

[SIMassey]

Could be.

Or they could just use a common b circuit regulator like many alts used, and bootstrap the alt to charging with close field contacts at startup, and then a cutout that pulls in after startup.

Check out this thread. Massey Ferguson 135 electrical woes. There is a picture of under the dash. On the right hand side, there is an oil line with what looks like a diaphragm switch with two wires. I believe this was what was described in the other thread I was speaking of. If these two wires are connected, the battery may start charging, indicating a faulty switch. My tablet is giving me fits tonight. Thread was started by scott123456789.

 

[SIMassey]

Found a wiring diagram in this thread.
http://www.tractorbynet.com/forums/...intage/169437-massey-ferguson-135-wiring.html

That one is for a generator not alternator.

 

[Soundguy]

Check out this thread. Massey Ferguson 135 electrical woes. There is a picture of under the dash. On the right hand side, there is an oil line with what looks like a diaphragm switch with two wires. I believe this was what was described in the other thread I was speaking of. If these two wires are connected, the battery may start charging, indicating a faulty switch. My tablet is giving me fits tonight. Thread was started by scott123456789.

Like I said.. seems an odd solution for a non existing issue. External vregs and gennies and alts are simple automatic technology, regardless if the maker over thought it.
. 1, don't own a MF diesel, 2, never saw the need for a trick scheme for a gen or salt charge system.
I've heard of the same oil pressure switch scheme too, just never put much thought in it

 

[Soundguy]

Phone giving me fits too tonight!

 

[SIMassey]

Phone giving me fits too tonight!

Check out another related thread by "upland cattle dog" to confirm my suspicions. Farmwithjunk explains the same problem and solution.