g741.org

I'm paranoid, or am I?!

As some of you guys know I drive the M37 daily and I'm experiencing something new, the voltage of the electrical system is a stable 28v at idle, but occasionally it fluctuates with higher engine speeds. I notice it in the lights and with the voltmeter. I'm wondering if it's the regulator (orig. mechanical version) or the generator (orig. style of unknown mileage) causing the issue. The wiring and connectors are all in great shape.

I was wondering if anyone has suggestions for where to start digging.

We need to get ready do go off and do some snow camping .

Thanks,

Andy

It's most likely the Reg.
The points in the mechanical Regulator are bouncing (arching).
A good cleaning with a point file and cleaner and re-adjust.

It's covered in the electrical section of the TM, but the manual
Number escapes me at the moment.

Oh, just lightly file.
You don't want to remove to much, just smooth them out.
Tom

Tom,
Thanks. The regulator on the truck is one of the few parts that's gone untouched. Look like I have some research to do now . I feel guilty about cracking it open, it still has the lead seals on it!

If you happen to remember the TM please post.

Andy

TM9-1825B
Make sure it is the November 1952 or later issue.

What do you guys recommend for cleaning the points? I did some research yesterday and there were cautions included in some of the manuals about various abrasives.

I was thinking a small file and some business cards dipped in denatured alcohol. I assume the issue is getting grit in the assembly?

There were specific files for the job. It usually only takes one stroke to do the job. There is a chemical cleaner available at music stores called DeOxit that may work without filing. Then you won't have to go through the fun of adjusting the regulator without all the special tools.

just me,
We used to use that stuff on our engine harnesses years ago and I never could remember the name. The engine builder carried around a can of it, it worked great!!! Now I have a few cans on the way .

Thanks,

Andy

Cleaned the points with DeOxit today. That regulator sure is a neat piece of machinery! I can't imagine what it would cost to replicate today.

The points on the cut Out relay (the pair) had the most wear and oxidation. Those on the Current and Voltage relays looked new. I sprayed a tiny bit of cleaner on the points and let it sit a bit, then passed paper between the contacts, cleaned, repeated, and finally blew things out gently with air.

I'll report back on my results.

Andy

Home Depot still has points files available-I ordered one for less than $10 bucks-handy to have until I convert to the Pertronix (once I determine what model number distributor I have).
Gary