1940 248 Distributor rebuilding

I had my distributor put on a Sun analyzer today, and it basically flunked. Worn cam (up to +/- 2 degrees between cylinders), centrifugal advance way off (had to go to 3000 RPM to even get above 10 degrees), vac advance mechanism uneven (vac module is OK but breaker plate movement jerky and uneven). I might be able to fix or improve the advance problems, but not the cam issue, so probably the best thing is just go for a rebuild. Does anyone have any recommendations on someone who is good for this work?

BTW, I had also taken out the ignition coil but we didn't get that far in the testing - no need once we saw the initial results. The coil appears to be original - it is of the locking type and it was a bear to get the lock released. Resistances are to spec but I wonder if I should just put it on the shop wall at this point. Are the locking type coils unobtanium?

Cheers, Dave

So far I have:

Advanced Electrical Rebuilders, Michigan - seem to specialize in motors/gens, but do mention distributors

Ignition Engineering, Anaheim CA

Advanced Distributors, Shakopee, MN

Bubba's Hot Rod Shop, Speedway, IN

Classic and Exotic Service, Michigan

Anybody recommendations from these?

Cheers, Dave

Dave,

Rosedale Auto Electric in Beltsville rebuilt the generator for my '28. I don't know if they rebuild distributors but it may be worth asking. 301-595-2971 or 800-200-7083 or they might be able to tell who, locally, can.

Also might try Alexandria Armature Works in Alex VA

Dave

Thanks Dave! I tried Rosedale, they are now Tri-State Battery and have moved to Crofton. They still do starter/gen work, although reluctantly it appears. No distro work and no recommendations. AAW was also a bust. I'm still looking...

Cheers, Dave

If you found your timing varying up to +/- 2 degrees between cylinders, do you think your problem may also be due to worn drive gears on the distributor shaft, camshaft or both?

I hope not. Most likely is a bent shaft. The guy in Shakopee identified this and says he can straighten. Am shipping it up tomorrow.

I did fix the sticking vac advance today by replacing the breaker plate with a NOS one that I had. Uses the plastic bearings so isn't period correct, but the car's a driver so I'm not worried about that. The vac advance works good now.

I also erred in not doubling the degrees from the tester to get crank degrees. So I am good on the centrifugal at high rpm, but the low end of the curve is still off, advances too slowly.

Cheers, Dave

In working on the breaker plate, to get it to work smoothly, you have to be sure to clean the grove that the 3 balls run in. However it sounds as if your breaker plate might have been modified.. On the originals, getting the balls in correctly and then having them work smoothly is a royal PITA! Getting the 3 balls in the right place isnt easy.

In any case, there must be no radial slop in the breaker plate, otherwise the point gap will be all over the place.

Don:

You are quite correct. My old plate had the 3 balls, and 2 years ago I did a thorough clean out, and put grease on the mechanism to help it to move smoothly, but it wasn't enough. The plate movement was very jerky and uneven. The new plate, I assume from the late 40s, has 3 plastic bearings that fit into the slot that the balls were in formerly, with a key ridge at one end that fits into the slot formerly used to remove the balls to pull the old plate out. The new plate has 3 tangs designed to fit against these plastic bearings, with one being of spring material to provide a friction fit. Seems to work quite well, nice smooth movement.

Cheers, Dave

You learn something new every day - I had never heard of this distributor improvement.

Thanks for the info. I'd like to see a photo of that newer style.

A friend of mine had good experience with an outfit in Baltimore when he needed his generator rebuilt. I believe they did it for $40. I will check to see if they work on distributors since I am going to have them look at my generator and starter. Might as well get my distributor checked as well if they do.

Guy Weigand

1939 Special

.... ()... I'd like to see a photo of that newer style.

me too ...

OK, another thought.

If you look closely at the engine crossection in the service manual, you can see that there is an oil port on the dist. from the cam to the distributor and shaft. There is another hole opposite that on the dist. and below to let the oil out and back to the crankcase.

I checked one of my spare distributors to see if that is so. Indeed, there is one hole near the bottom just above the gear on the body (out?) and on the opposite side another hole slightly higher on the bearing (in?).

The lower hole is angled toward the gear and the upper hole is angled upward.

In the case of my spare distributor, both holes were plugged with sludge and almost invisible - I did an "excavation" to see where they went.

Just perhaps, one of those holes (out?) on your distributor is plugged and thus the oil from the cam is being forced into the body of the distributor rather than draining back into the crankcase. A long shot, but possible.

Don

Don et al:

Thanks. I ended up shipping it off to Shakopee yesterday, will let you know how it went.

Here are the pix of the new plate. The blue arrows point to the new plastic inserts that the plate rides on. Two of the plate tabs are regular metal and have no give, while the 3rd one is spring steel and provides a friction fit (2nd photo). You can see the lubriplate I put on the plastic bearings for test, apparently cam grease is what is recommended and that is what I will use when the unit comes back.

Cheers, Dave

Dave,

Thanks for the photos. That is a pretty neat upgrade. The old 3 ball assembly is a bit difficult to get working smoothly.

I wonder when Buick made the change? Or is that an aftermarket solution

Not aftermarket, it is a direct replacement, I have the Delco box it came in. I will get the Delco number later tonight or tomorrow.

Cheers, Dave

Delco number is 1914446

Hi,

My '40 LaSalle has the three-ball arrangement, and I assume the 37 Roadmonster does also, though I never looked. Fortunately, I had the presence of mind after the first attempt to assemble it to put down a towel to catch two of the little guys when they would fall out of place when trying to install the third one. Of course, there was a down side: I had to go shopping with the Boss for a set of matching new bathroom towels.

Once assembled though, it worked fine.

--Tom

Dave, I just bought the Delco part, it states 1946-49. My distributor housing has uneven wear in the groove at the point where the balls roll.. This Delco part should solve my problem. The box is unopened so hopefully the plastic parts will be inside with the plate. Thanks for the info... Tom

Sure, glad to help, or be the guinea pig anyways. Once you open the box you will see the plate and a small envelope with the 3 plastic bearings. Also an instruction sheet.

Cheers, Dave

Thanks for postin Dave, very interesting..my stored original 38 Dist has the same problem.

When I did my '38's, the breaker plate race was all crudded up on both cars (done 20 years a part). I just used a small wire wheel to clean the crap out of the distributor body race and a wire "toothbrush" to clean the breaker plate races. I replaced the balls with new ones from Mc Master Carr - I still have a million left - but they are cheap.

It is kind of a PITA to put together, but they work as designed now.

While I do like the upgrade, since the plastic parts have no give, they have to have clearance to work - thus breaker plate axial movement and the attendant point clearance change. (probably makes no difference though). The 3 balls with the spring load does not have this axial movement and will keep the points more precisely set.

I was going to go with a Pertronix but would still have had the breaker plate, advance weights, and all the parts inherent to the factory distributor so I modified an Oldsmobile HEI to use instead. When gas was $4 a gallon I was on a quest to get 17mpg in my 37 Special because we do l-o-n-g trips in it. One thing that was needed was a rock steady spark source and for that the GM HEI can't be beat. An added bonus is parts can be bought cheaply at any parts store. It absolutely would not be for anyone wanting to keep things under the hood looking factory but for a cruiser it's the cats meow. Went to 12v and radial tires for the same reasons. Since you said yours is a cruiser you may (or not) be interested. Either way good luck with your project.

Thanks Mac! A long way from that point yet, still just trying to get it to be reliable. Once I get to that point I will consider further upgrades, as long as they are reversible.

Don - not sure I understand. The new plate is also held in by a spring arrangement similar to the 3 balls.

Cheers, Dave

Dave,

I didnt realize that the new setup does have spring loading to eliminate slop (I couldnt see that). In that case it would be superior.

Don

Dave, my breaker plate arrived, got it installed, so now my new engine is ready to fire up(on engine stand). While doing this 41 distributor I decided to check my extra(`37- 663Y) and it has a different type breaker plate(not Delco). Breaker plate is a DYNA-FLYTE Mod. 880 This breaker unit does not use the groove in the distributor housing, the breaker plate has a guide ring on the underside that the breaker plate pivots on, the guide ring has 4 mounting tabs and is held in position with the two cap clip screws and one of the vac. adv. screws. Tom

I must say, this DYNA-FLYTE breaker plate is way better design than the Delco... Tom

I would recommend. Advanced Electrical Rebuilders, Michigan - seem to specialize in motors/gens, but do mention distributors

I was there today with my starter/generator/distributor and Jason does great work. The only problem that he has is that he is so good he is really backed up.

Here is his web site. http://www.aerrebuild.com/

Sounds like the one that i have too.. anybody knows when they change over to ball- less distributor ?

I drive my also with pertronix now (12V) after years of adventures with short living cheap china points and condenser-material .