Not Charging, opinions needed

[Wayne64]

Hi All, Today I took the M37B1 on an ammo run (not skeet ammo but food) The truck started and the meter was hard into the green range as usual. After shopping I fired it up and the needle was sitting dead center (in the yellow), on the way home it once jumped into the green then back to the center. I am not getting a charge measured at the battery box, so; What are the options for a combat disabled vet on a fixed income, also wanting to do the job once as I won't live forever
Should I go for the alternator up-grade? What all would I need (both price and parts)?
Does anyone offer a bolt in kit for this conversion ?
I will be pulling the tub this summer and the whole nose will be exposed and it would be a good time to handle this issue. BTW I'm sticking with 24 volts
Thanks Folks

[M37UK]

Hi All, Today I took the M37B1 on an ammo run (not skeet ammo but food) The truck started and the meter was hard into the green range as usual. After shopping I fired it up and the needle was sitting dead center (in the yellow), on the way home it once jumped into the green then back to the center. I am not getting a charge measured at the battery box, so; What are the options for a combat disabled vet on a fixed income, also wanting to do the job once as I won't live forever
Should I go for the alternator up-grade? What all would I need (both price and parts)?
Does anyone offer a bolt in kit for this conversion ?
I will be pulling the tub this summer and the whole nose will be exposed and it would be a good time to handle this issue. BTW I'm sticking with 24 volts
Thanks Folks

Wayne, I did the alternator upgrade and cant recommend it enough. Its a VERY simple wiring job and you can use the existing generator bracket. All you need is a long threaded rod to mount the unit on. You will also need
the pulley off your old generator. I had to have my old pulley lathed to make it fit as it was too deep for the alternator shaft.
If you go for the same type of alternator as mine you can expect it to start charging at very low revs, just over idle. Speak to Charles at M Series rebuild for the cost.

Cheers

[Wayne64]

Thanks Stu, threaded rod in all sizes is available to me (both Son's are Steamfitters). I'm also handy with my 1950s 10" Logan lathe. In the past I have seen alternator harnesses on eBay, is this what I need for wiring? Also does the alternator have a built in regulator?

[cuz]

The harness you see on Ebay are for the military 60 amp system alternator. The M37UK photo is a one wire Delco unit (built in regulator) you can get for under $100 at any decent local automotive electric shop. Simple to wire in.

The military 60 and 100 amp alternators are nice looking upgrades but they are getting higher and higher every week. The 60 amp alternators are running over $250. The 100 amp alternators are much higher and a real PITA to install and maintain.

Just pull your generator and regulator and remove the pulley and take the pulley to your local auto-electric shop and tell them you want a 60 to 90 amp Delco indexed for left lower engine mounting that your pulley will fit on. I prefer the two or three wire Delcos so I can switch the power at the main switch. You'll have to dicker a bit with the mounting and the adjusting bracket.

My email is listed. When you are ready to wire just email me.

[M37UK]

I prefer the two or three wire Delcos so I can switch the power at the main switch.

Wes, what is the benefit of being able to do that, does it mean you can manually stop the alternator from charging the battery?


Cheers

[cuz]

Well you could turn it on and off but the master switch will also turn the engine off. It provides for field excitation only when the main switch is on. This can protect the internal voltage regulator components from any electrical damage during maintenance and etc. In aircraft applications we actually fuse the field power from the master switch at about 5 amps and the main alternator field at at least 80 % of rated output.

[Wayne64]

I'm back, as I finally got some breathing room to do some searches. I do have a couple of questions still as I have decided it's going to be a Delco alternator. I'm not looking for big AMP output as I will never have the big draw items some might add. 50 Amps or more would be fine. Now there does seem to be a division on if 1, 2 or 3 wire is a better way to go. I never did a one wire and was wondering about low RPM output? Also some here mentioned using the stock Generator pulley. The reason I question that is the diameter of the stock pulley as most alternators I have installed had a much smaller diameter, which equates to faster rpm of the alternator. What I base my thinking on is years ago I fitted an under drive pulley set to my Son's Mustang. Cooling and charging were both off and we re-fitted the stock ones. Sorry about all the questions.

[cuz]

The lower RPM come in for the alternator can be done both internally and externally.

Here's a couple of sites that will help you:
http://www.angelfire.com/mo/bucketheads ... ewire.html
http://www.alternatorparts.com/FAQ.htm#how_to_wire
http://oljeep.com/gw/alt/edge_Alternator_Theory.html
http://bob_skelly.home.comcast.net/~bob_skelly/alternator_conversion/wiring_alternator1.html

[Wayne64]

Thanks in advance for all the input and this where I stand now with some final questions. I have ordered a new Delco 24v 70 amp 10SI single wire and that is on it's way. Today I pulled the original generator out and as I had a bad 10SI from my Jag conversion I started looking at the fab involved. My questions are as follows.

What sized threaded rod is used? Looks like if the bottom pivot hole on the 10SI is drilled to 7/16" that will work with the engine bracket.

Am I right that about 5/8" needs to be turned off the back snout of the generator pulley for the nut?

Which side of the front hole on the existing lower engine bracket does the 2" Delco lower pivot go, in front or behind?

Do I totally remove the wiring leaving the original regulator, or for now just unplug and remove the heavy cable on the starter solenoid? I know later I will have to add a volt meter which Saturn has.

I know everyone is saying it's a simple job and these answers will help this old guy with the bad back .

[M37UK]

Wayne

I used 12mm threaded rod which is just under 1/2"
I mounted the alternator pivot in front of the existing bracket. Remember that my truck is Canadian so yours may be different if you have the US engine.
You only need 2 wires, one that grounds to the truck frame or engine block and the other which is connected to the starter motor positive terminal.
Thats it !

You will no longer need the original regulator, so it can be removed along with the associated wiring.
I cant remember how much was lathed off my pulley as I never did it myself.

[Wayne64]

Thank you Stu, I now just have to spend the time to sort out all the bits of info I have found on the trucks wiring. Does anyone have good drawing of the complete M37B1 wiring? A link to one would be great, instead of the bits and pieces I've seen.