Alternator🤔

[Mogman]

Been tasked with sorting the charging of a manitou 732 had their fitter put a new battery on still won’t start so he put a new alternator on but still battery flat over night so they asked another ‘fitter’ to have a look, after a day he managed to put a direct feed from the battery to the alternator but still no joy

I had a look this afternoon and there is no dash lights on (so battery light not on no charge) took all the dash out and found a dodgy connector gave a good clean but still no dash lights

now when I put my hand on the alternator it’s too hot to touch so my thinking was/is it’s wired wrong (plus I think the new alternator is burned out

see this is what I have,
B+ is the big connector goes to a 60 amp fuse then the battery

But where do the other two connector too
I think W is warning light, but what about D+

I have two wires a red one and a green one that go the these connectors but which one goes where
#1 fitter is on his holidays now (and I use the word fitter in the looses possible way)

what’s your thoughts or has anyone got a manitou with a Perkins engine in to tell me which wire goes where then at least I can tick that off the problem

 

[DaveDCB]

Silly question- does it work with a new / fully charged battery attached?

 

[craig]

W sometimes is for a rev counter and D+ is warning lamp

 

[jd6820]

Been tasked with sorting the charging of a manitou 732 had their fitter put a new battery on still won’t start so he put a new alternator on but still battery flat over night so they asked another ‘fitter’ to have a look, after a day he managed to put a direct feed from the battery to the alternator but still no joy

I had a look this afternoon and there is no dash lights on (so battery light not on no charge) took all the dash out and found a dodgy connector gave a good clean but still no dash lights

now when I put my hand on the alternator it’s too hot to touch so my thinking was/is it’s wired wrong (plus I think the new alternator is burned out

see this is what I have,
B+ is the big connector goes to a 60 amp fuse then the battery
View attachment 49036
But where do the other two connector too
I think W is warning light, but what about D+

I have two wires a red one and a green one that go the these connectors but which one goes where
#1 fitter is on his holidays now (and I use the word fitter in the looses possible way)

what’s your thoughts or has anyone got a manitou with a Perkins engine in to tell me which wire goes where then at least I can tick that off the problem

B+ is the battery live

D+ is the warning lamp/ignition feed to excite the alternator

W is frequency for tacho

 

[Mogman]

B+ is the battery live

D+ is the warning lamp/ignition feed to excite the alternator

W is frequency for tacho

Cheers not got a tacho but still got three wires that go to the alternator

now the next question is after messing with a few ‘Green’ plugs and sockets I’m only getting 6-7 volts at the charge lamp (wasn’t getting anything before I un ‘greened’ a few plugs so I can only think there must be still a bad connection

oh I’ve had to put the old alternator back on as the ‘new’ one seems to be grounded on all the terminals to earth

so out of a red wire or a green wire which would you connect to the ‘exciter’ connector ( I think red)

 

[Mogman]

Silly question- does it work with a new / fully charged battery attached?

It will start and run but no instrument lights

 

[V8Druid]

It will start and run but no instrument lights

define instrument lights?

 

[Steve]

Does the manitou have an external regulator, usually near or in the battery box.

 

[jd6820]

Does the manitou have an external regulator, usually near or in the battery box.

Unlikely, I'll see if I have a wiring diagram but I'll warn you they aint good to follow and that comes from someone who's good with wiring diagrams...

 

[jd6820]

Wiring diagram is for a 627 but it'll be fairly similar to the 732. You need 12V one side of the bulb, this 12V is common across quite a few of the other dash bulbs so if no other dash lights start at the fuse panel. Is it one by the foot throttle on that model?

 

[V8Druid]

what breed is the alternator @Mogman ?

 

[Mogman]

Wiring diagram is for a 627 but it'll be fairly similar to the 732. You need 12V one side of the bulb, this 12V is common across quite a few of the other dash bulbs so if no other dash lights start at the fuse panel. Is it one by the foot throttle on that model?

I’m only getting 6v that is common to the bulbs (oil pressure, ignition etc.)

 

[Mogman]

Wiring diagram is for a 627 but it'll be fairly similar to the 732. You need 12V one side of the bulb, this 12V is common across quite a few of the other dash bulbs so if no other dash lights start at the fuse panel. Is it one by the foot throttle on that model?

Cheers for diagram will print it off

the W connector on the alternator goes to the hour clock

yea the fuse and relays are behind the foot throttle had it all disconnected and sprayed with ac90

 

[V8Druid]

I’m only getting 6v that is common to the bulbs (oil pressure, ignition etc.)

have you got a pair series'd up anywhere? ....
ignition switch in a bad way forming a dropper resistance??
does it have a dash voltage stabiliser unit and has it gone south?

stabiliser unit

 

[DaveDCB]

Is the Earth good?
I’ve had my telehandler misbehave with a loose earth, engine will run without it but dash died..

 

[jd6820]

Cheers for diagram will print it off

the W connector on the alternator goes to the hour clock

yea the fuse and relays are behind the foot throttle had it all disconnected and sprayed with ac90

Should be getting 12V nowt will work properly at 6V, either earth issue or corrosion, possibly on the fuse board, they are bad for it due to the location. Check the fuses in the holders at the bottom of the board. Usually on the back of the panel you take off to access the relays/fuses there is a diagram of what the fuses/relays do. Check voltages at each side of the fuses, the pins are exposed so leave the fuse in the holder and check each circuit.

 

[jd6820]

have you got a pair series'd up anywhere? ....
ignition switch in a bad way forming a dropper resistance??
does it have a dash voltage stabiliser unit and has it gone south?

stabiliser unit
View attachment 49043 View attachment 49044View attachment 49045

No voltage stabiliser in the dash just simply fuses, relays, switches and bulbs. No ECU apart from Load Monitor.

 

[Mogman]

Should be getting 12V nowt will work properly at 6V, either earth issue or corrosion, possibly on the fuse board, they are bad for it due to the location. Check the fuses in the holders at the bottom of the board. Usually on the back of the panel you take off to access the relays/fuses there is a diagram of what the fuses/relays do. Check voltages at each side of the fuses, the pins are exposed so leave the fuse in the holder and check each circuit.

That’s my thinking


Your wiring diagram has different colours going to the alternator
Will trace back to fuse box so that it is connected properly

Like I said too many ‘fitters’ been messing with it so I have to start from the beginning

 

[Mogman]

Well after a bit of dismantling

yes obitrol out with pipe work along with the heater duct just to get the fuse board out (to check for any broken traces)

found it has a broken wire somewhere in the loom between the engine bay and cab

so was going to run a new wire but found that air filter sensor was broken off so used one of the wires form it and connected to the alternator then swapped the other end to the charge light

oh and the new alternator has burned out because the idiot had put a direct feed from the battery to the D+ and left it connected, now the B+ goes straight to earth never felt an alternator so hot so stuck the old one back on and she’s charging like a power station now

cheers for the inputs

 

[tctractors]

The W connection is as already said for the Rev counter (Tacho) this puts out commonly half the battery voltage as it picks off every other pole, so 6 volts but un- rectified so A.C. power.