Distrib. rotor not turning. Engine cranking normally

D

DonChiotos

Junior Member
I have a 1928 Model A that the engine cranks normally, but the rotor in the distributor is not moving, so engine will not start. If I remove the distributor cap and try and turn the rotor, it will not move. I am in the process of trying to remove the distributor, but it is stuck! Does anyone have any ideas? Thanks
 
The distributor is stuck, so lots of corrosion in there at the base of the distributor. The distributor shaft is seized. You broke the drive gear tang down inside the valve chamber, at the center of the cam. A bit of work to replace broken and seized parts but not a big deal.
 
I am using the pry and tap method to get the distributor loose. Is this a good way to get it loose? Will the shaft and tang come out together or am I in for major machine work?
 
Check the timing gear before you take things apart.Turn the timing pin around,put it in the hole,and hold your thumb against it while cranking the engine by hand.If you can't feel the pin scraping the timing gear while you turn it over,the gear is missing a few teeth.You will still have to free the didtributer up,sooner than later you are going to have to work on that anyway.
 
I got the distributor out by the tap and pry method. (i just needed a bigger hammer). The shaft is corroded so bad the shaft will not turn. The shaft has a slot at the end that is in good condition. The tang that fits into this slot to drive the distributor I'm not sure what or even if it is still there. What does this tang get driven from? What is my next step. Do I pull the pan to see where it connects? Thanks
 
You will need to remove the valve cover and oil return pipe. Behind the valve cover is the distributor drive gear and retaining spring. Remove the spring and the gear will come out.

Has this engine run recently?
 

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Keith True said:
Check the timing gear before you take things apart.Turn the timing pin around,put it in the hole,and hold your thumb against it while cranking the engine by hand.If you can't feel the pin scraping the timing gear while you turn it over,the gear is missing a few teeth.You will still have to free the didtributer up,sooner than later you are going to have to work on that anyway.
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Sounds like when my cam gear stripped.
 
DonChiotos said:
I got the distributor out by the tap and pry method. (i just needed a bigger hammer). The shaft is corroded so bad the shaft will not turn. The shaft has a slot at the end that is in good condition. The tang that fits into this slot to drive the distributor I'm not sure what or even if it is still there. What does this tang get driven from? What is my next step. Do I pull the pan to see where it connects? Thanks
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If you turn the engine over with a hand crank, do you feel compression? If you do, the timing gear is probably good (the valves are opening and closing) and the distributor drive gear is broken.

You will want to pull the valve cover off to investigate. No machine work to be done. Just replace the distributor drive gear. Easy.
 
Next item to look at is take off the small timing gear cover and have a look at the gear. My guess is that the tight distributor has caused the gear to strip. Easy fix.
 
Don, First, welcome to the Barn and the Model A world. Please provide your location and please post some photos of your car when you can.

It sounds like this may be a "new-to-you" car. As the distributor was rusted solid my advice is to pull the engine and take it apart for a full inspection. Replace any parts that are broken and adjust the bearing clearance if needed. Do any other things as indicated.

The Model A engine is a simple beast, like a lawn mower engine. So it is easy to learn on. If you have any mechanical experience it will be a cake walk. Don't be afraid to dive right in. If needed you can get help fron members of your local Model A club, and of course from members of the Barn.
 
I got the cover plate off and looked at oil pump gears and the tang looks good. I put the shaft back in and the gear moves with cranking of the engine. It didn't do this prior to reseating the shaft. The distributor shaft still will not move with distributor out. So, I'll get a new distributor. Is it possible for the cam to turn the oil pump but not the distributor shaft, and not break any tangs or gears? As I said the distributor shaft is working now when cranking engine by starter.
 
There is a tang on both ends of the oil pump/distributor drive gear shaft, one tang fits into the oil pump shaft slot, the other in the intermediate shaft.

There is a slot on the other end of the intermediate shaft.

The tang from the distributor shaft fits into this slot, which is slightly off-center.

Could the distributor shaft tang be broken off and stuck in the slot in the intermediate shaft?

Some distributors have only one long shaft, but still have the slot/tang arrangement.

Pictures would help...
 
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Replacement shafts and distributor parts are available, assuming that you have an original type distributor...
 
IF the distributor shaft doesn't turn but the engine will you have something broken. you need to address each item as listed until you find what it is. Good luck and remember to have fun with your A.
 
Bob C said:
nope, nope, nope


He said he has the distributor out and the shaft won't turn.
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Which could have caused the cam gear to strip. The cam gear is the weak point in the design. Cheap and easy to replace in comparison to the cam or drive gear for the dist/oil pump shaft.
 
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