Battery drain!

[kmead]

Yes heat is the enemy however it can be appropriately combatted. Fiat figured out how to do so long ago and the parts to replicate it are available.

My 1985 alternator is doing fine with a regulator change after 36 years so this is not that big of a problem.

More electrical power available will be a good thing all around. The modifications to run this will be minimal, you can leave some of the old componentry in place and just extend a few wires.

You are actively making changes to the car which need more power, adding that capacity will be necessary. Although originally rated at 33amps, there is a very good chance it no longer makes that kind of power today.

 

[tvmaster]

No, the heat from the exhaust and the cooling system pipe negatively affect the early electronics of the solid state voltage regulator in the alternator, which is going to run hotter by itself in the first place because it's around 55-65 amp as compared to the original which was 33 amp. More power almost always = more heat.

Do you have a recommendation if I’m thinking of increasing my alternator amps to 65 - buy aftermarket instead of Bosch? Is a modern alternator more resilient to the engine bay temperature than the MWB alternators are?

 

[tvmaster]

Yes heat is the enemy however it can be appropriately combatted. Fiat figured out how to do so long ago and the parts to replicate it are available.

My 1985 alternator is doing fine with a regulator change after 36 years so this is not that big of a problem.

More electrical power available will be a good thing all around. The modifications to run this will be minimal, you can leave some of the old componentry in place and just extend a few wires.

You are actively making changes to the car which need more power, adding that capacity will be necessary. Although originally rated at 33amps, there is a very good chance it no longer makes that kind of power today.

Would Matt at MWB know the wiring modifications to make, as I wouldn’t?

 

[kmead]

Matt knows nearly everything, Dan Sarandrea knows all the rest...

I will have a gander at the wiring diagrams and get back with you. I suspect it is not using one wire and adding one other.

 

[dllubin]

I think you just need to connect the B+ terminal to the cable going to the battery via the starter cable and the D+ cable going to the alternator light.

 

[tvmaster]

I think you just need to connect the B+ terminal to the cable going to the battery via the starter cable and the D+ cable going to the alternator light.

Regarding the service manual and some logic - let’s say you were running the headlights, heater and windshield wipers (can‘t think of being able to turn on anything else at the same time with a substantial draw), how would you measure the amount of amps those three would demand simultaneously? Would a simple multimeter suffice, or would discovery be more complex...
Granted there are amp ratings beside each fuse designation, those are grouped in a way that calculating their real-life load would be difficult.

 

[dllubin]

You could use a multimeter if it had a high enough ammeter rating but most are in the 2 to 10 amp range. You could measure the current draw in each circuit individually by removing the fuse and connecting the ammeter across the terminals. I've got an old ammeter that goes to 50 amps. If the current is much higher than the ammeter rating, it will be destroyed.

 

[tvmaster]

You could use a multimeter if it had a high enough ammeter rating but most are in the 2 to 10 amp range. You could measure the current draw in each circuit individually by removing the fuse and connecting the ammeter across the terminals. I've got an old ammeter that goes to 50 amps. If the current is much higher than the ammeter rating, it will be destroyed.

maybe it's time for another tool?

KAIWEETS Digital Clamp Meter T-RMS 6000 Counts, Multimeter Voltage Tester Auto-ranging, Measures Current Voltage Temperature Capacitance Resistance Diodes Continuity Duty-Cycle (AC/DC Current): Amazon.com: Industrial & Scientific

KAIWEETS Digital Clamp Meter T-RMS 6000 Counts, Multimeter Voltage Tester Auto-ranging, Measures Current Voltage Temperature Capacitance Resistance Diodes Continuity Duty-Cycle (AC/DC Current): Amazon.com: Industrial & Scientific

www.amazon.com

 

[ng_randolph]

For what you are doing, do what Don suggested; measure each load separately. Use a regular, cheap, multimeter. A clamp ammeter like the one you linked to has fairly limited use. I have one, and have used it exactly once in 10+ years.

 

[tvmaster]

For what you are doing, do what Don suggested; measure each load separately. Use a regular, cheap, multimeter. A clamp ammeter like the one you linked to has fairly limited use. I have one, and have used it exactly once in 10+ years.

So I took the X down to my local, who had a clamp reader. Turns out the alternator is producing 10 amps before turning things on? After turning the lights on, battery went down to 11.4 volts, with the engine running. However, it took a while to get a reading he could trust. And of course, revs didn’t get up as high as they may need to be for proper charging?
AAA has a driveway service for checking batteries/alternators, and I‘m a member, so I’ll see what they find. It’s not looking good for the ol’ 33amper though. F@#$...

 

[tvmaster]

You could use a multimeter if it had a high enough ammeter rating but most are in the 2 to 10 amp range. You could measure the current draw in each circuit individually by removing the fuse and connecting the ammeter across the terminals. I've got an old ammeter that goes to 50 amps. If the current is much higher than the ammeter rating, it will be destroyed.

Do you recognize what the additional wires on the + side may be? The fused, yellow line may have something to do with the 2nd radiator fan Ant added, since he mentioned putting in a relay somewhere. I was assuming this is that relay? But the red and brown(?) wires, I’m not quite sure. it the greatest looking jobs though? With no schematics of the aftermarket work done, I’m at a loss...and yes, they put in the wrong size battery I believe....

 

[kmead]

To be honest that is a rather sad assemblage.

The main feed (heavy black wire) has a poorly executed crimp. The brown wire (feeds the many ancillaries) is little better and then the red wire which then transitions to yellow or butterscotch to feed the relay which is apparently for the second fan.

I am also not a fan of the battery clamp chosen. There has to be a decent automotive electrician locally who has a proper hydraulic crimper who could provide you with good quality crimped wires and replace the horror show for power into the that lonesome relay.

You could trace the wires yourself, there isn’t much that is new there. Creating your own mini wiring diagram is neither difficult nor all that time consuming, you just need to be a bit of a Sherlock Holmes to ferret out the details.

You could invest in the tools to make the proper crimps but being a one time use may not be worthwhile.

 

[tvmaster]

To be honest that is a rather sad assemblage.

The main feed (heavy black wire) has a poorly executed crimp. The brown wire (feeds the many ancillaries) is little better and then the red wire which then transitions to yellow or butterscotch to feed the relay which is apparently for the second fan.

I am also not a fan of the battery clamp chosen. There has to be a decent automotive electrician locally who has a proper hydraulic crimper who could provide you with good quality crimped wires and replace the horror show for power into the that lonesome relay.

You could trace the wires yourself, there isn’t much that is new there. Creating your own mini wiring diagram is neither difficult nor all that time consuming, you just need to be a bit of a Sherlock Holmes to ferret out the details.

You could invest in the tools to make the proper crimps but being a one time use may not be worthwhile.

I’m fine doing some investigation. If you have a battery clamp link I’ll take a look for sure. I’m also certain I can get it cleaned up locally, instead of adding more one-time tools. I don‘t understand relays at all, but I imagine Youtube as answers. The brown wire - any chance that has something to do with the ‘brown wire mod’ I read about here?

 

[ng_randolph]

I’m fine doing some investigation. If you have a battery clamp link I’ll take a look for sure. I’m also certain I can get it cleaned up locally, instead of adding more one-time tools. I don‘t understand relays at all, but I imagine Youtube as answers. The brown wire - any chance that has something to do with the ‘brown wire mod’ I read about here?

From the factory, there is supposed to be a somewhat heavier gauge brown wire going from the battery. The BWM involves this wire, but there is nothing in your photos that suggests that a brown wire mod has been done.

And I think Mr. Mead was being very polite when he described this rat's nest as a "rather sad assemblage". I would make it a priority to get this cleaned up; the shoddy crimp on the black wire is the sort of thing that could leave you stranded. I would also sort this out before worrying more about the alternator issue you brought up in a different thread.

 

[tvmaster]

From the factory, there is supposed to be a somewhat heavier gauge brown wire going from the battery. The BWM involves this wire, but there is nothing in your photos that suggests that a brown wire mod has been done.

And I think Mr. Mead was being very polite when he described this rat's nest as a "rather sad assemblage". I would make it a priority to get this cleaned up; the shoddy crimp on the black wire is the sort of thing that could leave you stranded. I would also sort this out before worrying more about the alternator issue you brought up in a different thread.

All these electric issues are tied together, and yes, it is a lttle shoddy. Hence why I’m seeking opinions
BMW?

 

[kmead]

The BWM adds a second brown wire to the ignition switch to better power the various switched elements down stream of the ignition switch. It would be an added wire to the battery and would join the wire providing power to the ignition switch.

The better way to do the clamp would be one where the main wires (black and brown) are crimped into the clamp itself. If the additional brown wire could be added to the crimp for future upgrade it would be worthwhile. At the very least having them do a proper 10ga wire to eyelet connector with 8’ of wire for future use would be worthwhile.

 

[tvmaster]

The BWM adds a second brown wire to the ignition switch to better power the various switched elements down stream of the ignition switch. It would be an added wire to the battery and would join the wire providing power to the ignition switch.

The better way to do the clamp would be one where the main wires (black and brown) are crimped into the clamp itself. If the additional brown wire could be added to the crimp for future upgrade it would be worthwhile. At the very least having them do a proper 10ga wire to eyelet connector with 8’ of wire for future use would be worthwhile.

ok. 8’ of BW, just rolled up, going nowhere, just in case. As far as the additional wires coming off the relay, etc, those get added via screw-on, butterfly nut?

 

[tvmaster]

Looks like AAA suggested the dying alternator may have begun to kill the 18-month old battery.
So it looks like I’ll be replacing the incorrect size group 26 then...

 

[dllubin]

The factory size was 24F but you can get much smaller batteries now with at least the same capacity and lower weight. I made some spacers to keep my smaller battery in place.

 

[tvmaster]

The factory size was 24F but you can get much smaller batteries now with at least the same capacity and lower weight. I made some spacers to keep my smaller battery in place.

I do have the tray and cover, and it would be nice to keep using both. When you say smaller, thats still in the group 24, or 24f? Everyone pointed out my Group 26 was wrong.