The Stovebolt Site Forums The Shop Area The Electrical Bay Starter help needed

Hey guys, I have a 54 3600 that needs a new starter. The truck has been converted to 12V since when I bought it it has always had a 12v battery. It has cranked slowly for years but finally gave up the other day and I took the starter off and apart and the insides are shot. The brushes are literately worn down to the arms that hold them.... Can I use a 6v starter or does it have to be for a 12V system? I don't see where they are different in my research. A lot of the other components are but seems the starter can use either 6V or 12V? Any help/advise is appreciated.

Stroehlman - Without knowing what was involved in your "12V" conversion, we need more info on some related things on your truck. Whats the tooth count on the flywheel???

You can refer to this recently added Tech Tip Flywheels and Starters - 6 volt vs. 12 volt for help on figuring out what you have as well as help on ID'ing what starter you will need. Let us know more when you've checked the Tech Tip out.

I have a 6v starter on my '52 GMC (same part number as Chevy) that has been running well on 12volts for over 40,000 miles. As long as you don't crank it for too long it'll do fine. I did a backyard overhaul on mine about 10,000 miles after I bought the truck. It was making funny noises which were caused by the brushes worn down so far that the brush holders were touching the armature. Here is the write up from then.

The starter on my '52 150 GMC began making funny noises a few weeks ago. I decided to overhaul it myself, with a little help from my buddy Bill.

Some research showed that the most likely starter for my truck was part number 1107108. I got on O'Reilly's web site and found the following BWD (Borg Warner) parts:
Starter drive (Bendix) SD212
Drive end bushing SB65
Commutator end bushing SB0
Brushes (set of 4) X265
Brush spring (need 4) SC204

Removed the ground wire from the battery, then all wires from the stomp starter switch.

Took the starter apart and cleaned everything up well. Under a layer of paint from a previous overhaul, I found the starter part number 1107108 as I hoped and a build date of Aug 3, 1952, newer than my truck. Painted all the exterior parts.

The Maintenance Manual warned against using Emery cloth on the commutator. My buddy Bill (retired electrician at an Exxon gas plant) said that was because the dust will conduct. I used regular garnet 220 grit sandpaper to clean up the commutator and then Bill used a modified hack saw blade to clean out the gaps and undercut the mica insulators.

We cut the old bushings out with a small chisel, folding the bushing material into the center of the hole. Then we carefully installed the new bushings using the back side of a 9/16" socket as a driver and tapping gently with a hammer.

Replaced the springs and brushes one at a time so I could look at the other 3 to make sure I was putting it back together correctly. Left the brushes slightly loose in their holders. Installed the commutator end plate onto the armature and then tightened the screws holding the brushes once they were properly positioned.

Used a small dab of high temp grease in both bushings and on the pivot point of the arm that throws the starter drive in.

Bolted everything else back together and re-installed the starter.

A tip for getting the starter back in by yourself. Get a 2"-3" 5/16" bolt and nut. Put the bolt through the hole in the top end of the arm that activates the starter switch and turn the nut on a few turns. Makes a good handle to hold the starter while getting the nut on the top mounting stud. Once the nut is on the top stud a few turns, crawl underneath and install the underside bolt all the way tight before you finish tightening the nut on the top.

Don't forget to wait until all the starter wires are installed before connecting the battery ground cable.

WORKS GREAT!

Gdads51 - the bushing hole diameter is .446 with my digital caliper indicating from the tech info 12V starter, but the flywheel (9 teeth spacing) measurement is 2.81 indicating 6V flywheel.... What now? Also the inside of the starter only has 2 windings installed not 4 but the brushes are gone! They are worn all the way down to the arms that hold them so it has to be rebuilt or replaced. I'm just trying to figure out what to get?

As the tech tip indicates, you have to match the starter with the flywheel teeth. Sounds like someone may have put a 12V starter on a 6V flywheel. Like Bill said above, a 6V starter should work fine on 12V.

Stroelman - Your measurements do seem to be at odds with the Tech Tip info. I suppose it's possible that your starter has had previous repairs/rebuilds and may be made up of a conglomeration of parts and pieces. Guessing that your previous experience with the starter, when it did work, did not include grinding or frequent missed starter drive to ring gear engagement??? If that's accurate then it's at least correct for your existing flywheel.

To possibly learn more on what your current starter is, I would suggest a thorough cleaning and search for the stamped part number and date code on the case exterior. Then post that info here and we can try and help confirm what the starter is, which can lead to helping you find rebuild parts (they are still out there as noted in Bill Hanlon's post above) or a suitable replacement.

As Bill mentions above, doing the rebuild yourself is a good possibility. At the same time, have you searched for a local starter rebuild shop? Some can still be found, although that is becoming harder and harder these days.

thanks fellas. I ordered a 6V rebuild kit and plan to clean it up (already did some today) and will put the new brush's and springs in when they arrive. I do believe it may be a bit of a frankin-truck but up until now it has started just fine with no slipping or grinding in the past. One funny thing about this process is that the starter button on top of the starter did not have the wire connected from the small bolt to the + side of the coil for the extra spark at cranking time (it is a 12V coil). I will add that wire and see if the starts are quicker with it installed. Thanks for the replies and I'll let you know if the rebuild works. Again, Thank you very much for the feed-back. It is VERY much appreciated!

but just to add more flavor to the pot the starter is stamped with 12V number 1107634 YY. but it only has 2 windings in it not 4?

Stroehlman - Here's some added info on your starter based on the "1107634" stamped part number. Not sure what the "YY" stands for as most date codes after the part number were 3 alpha-numeric digits. Perhaps the "YY" stands for a service replacement starter as the same number was assigned to both original starters and service replacements? According to info in GMPartswiki your starter was used on 1955-59 6 cylinder 12 volt equipped trucks for Series 3 - 6 as well as some similar GMC truck models of the same years.

It is in fact a 12 volt starter that would have been used with the 168 tooth flywheel ring gear, unless someone modified it to change the bendix drive for an earlier 139 tooth ring gear???

Below are screenshots from a 1969 Delco Remy Service Parts Catalog. The number "1107634" is identified as part of their "Cranking Motor - Group 53-H". If you look through the detailed listing of components, it shows your starter only has the 2 field coils as no "Coil - Shunt" part number is listed. Nothing odd about this, just the way it was designed/built. You can also see the specific component part numbers for starter service parts as they are directly related the the stamped starter part number.

Hope this may be of some help with yours and possibly other Bolters starter questions.

The simplest solution for you is to buy a 6 Volt starter (post an ad here in the swap meet.) That way you won't destroy the starter bendix or the flywheel gear. I don't believe Dan''s statement that someone swapped the bendix for a 6V one is possible. They're quite a bit different.

Maybe someone will swap you a rebuildable 6V starter for your 12V starter.

Or buy a new 6v stomp starter from NAPA for $70 $155.

Just a year and half ago I bought a new one for $70 with a $15 core deposit. I kept the core.

Otto - If you read the entire thread you’ll see there is some conflicting information on the flywheel ring gear measurement (seems to indicate a 139 tooth flywheel which would be correct for an original ‘54 3600), but his existing starter is a 12 volt model originally used in ‘55-‘59 trucks. Which evidently worked for years without the grinding expected from a mismatched starter drive and ring gear.

For me, if it worked properly before and just needs a refresh, that’s more likely to be a less expensive solution that results in a known previously working unit back in service.

I don't know if your flywheel is on or off truck...but it would be a good idea to count the teeth. Count the teeth for 90 degrees of the diameter and multiply by 4. So you/we can be sure of our advice

Dan's great info shows the PN as a 12V for 6 Cyl. Pretty nice. I didn't know about it. I don't understand this yet...

"It is in fact a 12 volt starter that would have been used with the 168 tooth flywheel ring gear, unless someone modified it to change the bendix drive for an earlier 139 tooth ring gear???"

It's a 12V starter used on 6 cyl motors. 6 cyl has a 139 tooth flywheel? So I would have thought this "special" starter would have been designed with a pinion gear that mates with a 6 cyl 139 tooth flywheel.

Or ...

You’ll just need to crawl under the truck, pull the flywheel pan from the bottom of the bellhousing and measure from the top of any tooth to the top of a tooth that is nine teeth away, as shown in the two pictures above. On a 12-volt ring gear, the distance will be about 2.363”. The same measurement on a 6-volt ring gear will be about 2.789”.

The starter can have 2 field coils, that is not indication of voltage.

BILL, He did those measurements already. He got 2.81, close to 12V number. He got bushing ID at .024 smaller than tech tip number. Bushings don't get smaller with wear. But being "under" a little still indicates 12V.

Don't know if the YY was stamped on starter housing or on a metal tag. If there is a metal tag, don't know if red or black.

Only thru 55.1 models (give or take a little) did 6 cyl motors have 139 tooth flywheels. After that, they would have had a flywheel with 168 teeth which mates up with a 12V starter.

Otto, I looked on NAPA's website earlier and they said out of stock in my area. But checking a different area (SOCAL) shows them available for $180.

Wow! I'm amazed at the huge increase in price over such a short time. I guess Ol' Roy's broke at just the right time.

$162 in Springfield, IL. Don't know why that should make a difference.

Thanks Kevin for the explanation. This is why it's a good idea, in my opinion, to actually count the teeth as I mentioned. So as not to use this "new rebuilt" starter with the wrong flywheel.
But it has "worked" for years, albeit slow crank, according to Stroehlman. Too much oddity here, sort of, not to be sure/safe.

I do realize the measurement indicate someone did change flywheel on this 1954.

If starter is not geared for a 139 tooth, what is the reason for this starter to be designated a 12V for 6 cylinder? Is it the mounting pattern of the starter to bell housing being different 55.2-59, for 6 and 8 cylinder?

Stroelman did measure the tooth spacing, indicating that his flywheel is for a 6V starter with 139 teeth. I was the one that provided the 9-tooth dimension for the tech tip and counted all the teeth on the flywheel I measured. And if his starter is actually a 12V, then it's mismatched with his flywheel. It may have worked until now, but will eventually damage either the starter or the flywheel.

The starter mounting for 6 cylinder engines would be the same at least from 1947 thru 1958. I had a 1958 235 that had a 47-53 bell housing, 139 tooth flywheel, and 6V starter which I think someone was going to install in a 1937 pickup.

thanks Kevin, I will stop with the questions.

As with all repairs I make to this truck..... always more questions than answers. It does wear me down after a while. It is just an old dualy farm truck I take to town every now and then at a top speed of 45-50mph so I get honked at a lot too. But anyways the brush's in the starter are gone all the way down to the holders. I spent a lot of time looking for truly square brush's like the ones in the starter not the tapered at one end brushes all the info on the nets keeps telling me to get... When the brush's get here I will install them after I have cleaned everything up and see what happens. If that doesn't work I'll head down the next rabbit hole but probably try Kevin's idea of a trade.
I do have one question I know you guys can answer. I guess my idea was wrong but do the number of coil assembly's not determine if it is 6V or 12V? 2 coils = 6V, 4 coils = 12V?
Thank you guys for your help!!!

Sorry guys, I didn't see the second page of this tread. Yes the measurements indicate 6V flywheel and the 12V stamp on the starter housing says what it is. I should definitely have a 6V starter but as I said before it has not been a problem up till now. I will see if the new brush's fix it or I will look for a 6V starter. Again Thank you very much for your wisdom and advise. Very hard to get help these days and a place like this forum is AWESOME!

The quick answer is no, the number of coil assemblies doesn't always determine voltage. Your particular numbered starter is a prime example. If you refer to my reply post above you can see that yours wasn't designed with 4 coils. Only 2 "field coils" as noted in the components list.

Looking forward to hearing how the brush replacement and testing turns out.

According to a post by hot rod Jerry, the no. of field coils relates to torque.

As you know there is more to a rebuild than brushes. Bronze bushings, commutator, good solder joints, brush springs and tiny bit of oil in felts or oil holes......One of the MOST important things for starting is BIG new cables terminated and clamped to shiny clean positive posts and studs. Negative cables to clean negative posts and all grounding to shiny metal spots.