Alternator issue on 40xt

[ben@g2g]

Our 40xt has needed jumped everytime it's been started the past week. I pulled the battery out and cleaned it up last night. Charged it over night, and it's looking like it's good. Got the machine running, and it's not charging. Is the voltage regulator part of the alternator on this machine? Is there a way to test that? Can the alternator be cross-referenced at a parts store, or will I have to go to Case? My other option is to take it out to be rebuilt. Thanks for any info on this subject. ben

 

[Tazza]

The regulator should be part of the alternator. They usually have the brushes attached. Hopefully its as simple as removing 2 screws and removing the module. If its a generic alternator, you don't need to deal with your dealer. I suspect its something common that you could get parts after market, most do it this way.
The away i found to check this, is check the battery voltage with a meter. Start the engine and see what its reading. It should jump to about 14.4v when charging.

 

[ben@g2g]

The regulator should be part of the alternator. They usually have the brushes attached. Hopefully its as simple as removing 2 screws and removing the module. If its a generic alternator, you don't need to deal with your dealer. I suspect its something common that you could get parts after market, most do it this way.
The away i found to check this, is check the battery voltage with a meter. Start the engine and see what its reading. It should jump to about 14.4v when charging.

Cool. I'm going to pull the cab later this week, and make sure there are no loose wires, then I might take it in to the local generator shop for a rebuild, rather than messing with it myself.

 

[Tazza]

Cool. I'm going to pull the cab later this week, and make sure there are no loose wires, then I might take it in to the local generator shop for a rebuild, rather than messing with it myself.

Thats not a bad idea. Even if its just the regulator or brushes, they can at least spin it up on their test bench so they know 100% that its ok.

 

[aaa123]

Cool. I'm going to pull the cab later this week, and make sure there are no loose wires, then I might take it in to the local generator shop for a rebuild, rather than messing with it myself.

Before you do a bunch of work, check it first with a meter like Tazza said. While running if you read 12 or so volts, the alternator is not charging. If it reads 14 or so volts, the alternator is fine and something else is wrong. It's not uncommon for an old battery to get a flaky cell and be unreliable for starting. Does the battery show 12.6 or 12.7 volts resting voltage?

 

[ben@g2g]

Before you do a bunch of work, check it first with a meter like Tazza said. While running if you read 12 or so volts, the alternator is not charging. If it reads 14 or so volts, the alternator is fine and something else is wrong. It's not uncommon for an old battery to get a flaky cell and be unreliable for starting. Does the battery show 12.6 or 12.7 volts resting voltage?

Well yeah...I found out it wasn't charging before posting my first question. The battery is definitely fine passed the load test, and started the machine at least 15 times yesterday without issue. The alternator is just not charging, or at least getting it to the battery. Battery is roughly 12.5 volts, and no difference when running.

 

[aaa123]

Well yeah...I found out it wasn't charging before posting my first question. The battery is definitely fine passed the load test, and started the machine at least 15 times yesterday without issue. The alternator is just not charging, or at least getting it to the battery. Battery is roughly 12.5 volts, and no difference when running.

Ah, sorry, I didn't read carefully. Cheers!

 

[ben@g2g]

Ah, sorry, I didn't read carefully. Cheers!

Well, Case wants $200 for the alternator, and they don't list the voltage reg., or brushes separate. Surprisingly I was thinking Case would be charging over 300 with their usual inflated pricing. Funny thing is cross reference at local auto parts store was over $300. Still haven't made it into the shop to check out the fuses/wiring on the machine. Will do that before ordering.

 

[skidsteer.ca]

Well, Case wants $200 for the alternator, and they don't list the voltage reg., or brushes separate. Surprisingly I was thinking Case would be charging over 300 with their usual inflated pricing. Funny thing is cross reference at local auto parts store was over $300. Still haven't made it into the shop to check out the fuses/wiring on the machine. Will do that before ordering.

Stills seems like enough, I'm forever greatful to my local alternator/starter guy who always ssems to get me running for under $100 with a complete rebuild, whileI wait and watch usually. Most i ever gave him was 180 for 24volt starter off a 250 hp L10 Cummins, and it needed fully rebuilt and a new field.
He is also the one that pointed out the Korean Mondo alt that Bobcat uses is a direct bolt in for a Delco 60 amp.
What brand is the Case alternator and what does it look like? (pics please if you have them)
Ken

 

[ben@g2g]

Stills seems like enough, I'm forever greatful to my local alternator/starter guy who always ssems to get me running for under $100 with a complete rebuild, whileI wait and watch usually. Most i ever gave him was 180 for 24volt starter off a 250 hp L10 Cummins, and it needed fully rebuilt and a new field.
He is also the one that pointed out the Korean Mondo alt that Bobcat uses is a direct bolt in for a Delco 60 amp.
What brand is the Case alternator and what does it look like? (pics please if you have them)
Ken

Yeah I talked to one of the local generator shops. They said depending on what model Bosch Alternator it would be between 55 and $75 most likely. So I'm going to pull it off on sunday, hopefully get it rebuilt on my way home from my other job Monday, and then install it Monday evening. Sorry no pictures of it.

 

[ben@g2g]

Yeah I talked to one of the local generator shops. They said depending on what model Bosch Alternator it would be between 55 and $75 most likely. So I'm going to pull it off on sunday, hopefully get it rebuilt on my way home from my other job Monday, and then install it Monday evening. Sorry no pictures of it.

Pulled off the alternator this weekend. Man was that a pain. One of the hardest parts to reach. I'm not looking forward to putting it back on tonight. When I took it off, I actually pulled the whole belt tensioner, because I couldn't figure how to release the tension on it. I think I may pull the oil filter, and do an oil change(which is needed anyway) when I reinstall. The oil filter is right in the way of easy access to one of the mounting bolts of the alternator.

 

[ben@g2g]

Pulled off the alternator this weekend. Man was that a pain. One of the hardest parts to reach. I'm not looking forward to putting it back on tonight. When I took it off, I actually pulled the whole belt tensioner, because I couldn't figure how to release the tension on it. I think I may pull the oil filter, and do an oil change(which is needed anyway) when I reinstall. The oil filter is right in the way of easy access to one of the mounting bolts of the alternator.

Alternator shop verified it was bad, and installed a new regulator, and brushes. Re-checked it, and all was good. Got it installed on the machine, and it's still not charging the battery. All the wiring looks OK, but I couldn't trace every wire completely. What else would cause a no charge? Fuses look ok, unless there are more fuses hidden somewhere other than the fuse box. What about relay's. Would the charging run through them by chance? Anyone have a wiring diagram for a 40xt or something similar, so I can get a better idea what to look for? Goose, you seem like the answer man...any ideas? Thanks

 

[Tazza]

Alternator shop verified it was bad, and installed a new regulator, and brushes. Re-checked it, and all was good. Got it installed on the machine, and it's still not charging the battery. All the wiring looks OK, but I couldn't trace every wire completely. What else would cause a no charge? Fuses look ok, unless there are more fuses hidden somewhere other than the fuse box. What about relay's. Would the charging run through them by chance? Anyone have a wiring diagram for a 40xt or something similar, so I can get a better idea what to look for? Goose, you seem like the answer man...any ideas? Thanks

Open diode maybe? they usually feed power to the alt via a diode.... Its a possibility...

 

[ben@g2g]

Open diode maybe? they usually feed power to the alt via a diode.... Its a possibility...

Hmm...any idea where that would be? Is that a diode that's activated when the ignition is switched on?

 

[Tazza]

Hmm...any idea where that would be? Is that a diode that's activated when the ignition is switched on?

It could be anywhere in the harness from the key switch to the alt. The diode stops power from the alternator going back to the switch preventing the fuel solenoid from dis-engaging. This was a real problem for the old petrol engines, not so much diesel's.

 

[ben@g2g]

It could be anywhere in the harness from the key switch to the alt. The diode stops power from the alternator going back to the switch preventing the fuel solenoid from dis-engaging. This was a real problem for the old petrol engines, not so much diesel's.

I was looking at the parts diagram, and the only diode listed on the machine is in the wiring harness under where the front door would be. I haven't done a lot with trouble shooting on charging problems when it wasn't the alternator(if you can't tell). There are 3 wires on the back of the alt. I know the bigger stud, connects to the wire going to the starter/battery. Then there is a smaller stud, and a spade connector. One of those is the exciter wire from the ignition switch(and would go through the a diode), and the other is the battery warning light, for conditions under 12volts. Which of those 2 is which? If I use a tester on the exiter wire at the alt, it should show 12v with the ignition on correct? With the ignition off will there still be voltage from the alternator side? If there is no voltage coming from the ignition on the exiter switch I can just jump 12v from somewhere else temporarily to get it charging, until I can find the issue correct? Would that drain the battery while the machine is sitting?

 

[skidsteer.ca]

I was looking at the parts diagram, and the only diode listed on the machine is in the wiring harness under where the front door would be. I haven't done a lot with trouble shooting on charging problems when it wasn't the alternator(if you can't tell). There are 3 wires on the back of the alt. I know the bigger stud, connects to the wire going to the starter/battery. Then there is a smaller stud, and a spade connector. One of those is the exciter wire from the ignition switch(and would go through the a diode), and the other is the battery warning light, for conditions under 12volts. Which of those 2 is which? If I use a tester on the exiter wire at the alt, it should show 12v with the ignition on correct? With the ignition off will there still be voltage from the alternator side? If there is no voltage coming from the ignition on the exiter switch I can just jump 12v from somewhere else temporarily to get it charging, until I can find the issue correct? Would that drain the battery while the machine is sitting?

Run a jumper wire from the large (usually) red wire on the alternator to the battery,
Start the engine and see if it charges. If it does not , take a test light and see if the small wires to the back of the alternator have power going to them while its running. If not put power to the field terminal. this should make the alternator charge at full output.
I not familar with this machine but that should make most alternator charge if they are good. Sounds like you have a wiring problem somewhere.
Ken

 

[ben@g2g]

Run a jumper wire from the large (usually) red wire on the alternator to the battery,
Start the engine and see if it charges. If it does not , take a test light and see if the small wires to the back of the alternator have power going to them while its running. If not put power to the field terminal. this should make the alternator charge at full output.
I not familar with this machine but that should make most alternator charge if they are good. Sounds like you have a wiring problem somewhere.
Ken

Yeah that's the plan. Hopefully I can make it out tonight to do a little more troubleshooting. I was looking over the wiring diagram for the 1835(only electrical schematics I could find close) and it shows the field connection running off of the head light fuse. Wiring goes from the ignition switch, through headlight fuse, and then splits to the light switch one way, and then to the diode -->resistor-->alternator the other way. I just had them check and the headlights aren't working, so it could just be a bad fuse for the headlights causing the no charge problem. Well if the 40xt is wired similar to the 1835 anyway. Lets hope so...that would be easy.

 

[ben@g2g]

Yeah that's the plan. Hopefully I can make it out tonight to do a little more troubleshooting. I was looking over the wiring diagram for the 1835(only electrical schematics I could find close) and it shows the field connection running off of the head light fuse. Wiring goes from the ignition switch, through headlight fuse, and then splits to the light switch one way, and then to the diode -->resistor-->alternator the other way. I just had them check and the headlights aren't working, so it could just be a bad fuse for the headlights causing the no charge problem. Well if the 40xt is wired similar to the 1835 anyway. Lets hope so...that would be easy.

Ha...so it was the head light fuse. Not sure if it blew before or after the alternator went bad. It's all good now. Now I just need to find the gasket for the Hydro filler cap they lost. It never ends =)