My Distributor Cam Screw is Stuck

blindenlaub

Junior Member
Hello everyone, I am a new Model A owner. I purchased a 1929 roadster about 2 months ago. It is equipped with an FSI electronic ignition, so the distributor has an aluminum magnet sleeve instead of a points cam. I don’t think the timing has been adjusted since the electronic ignition was installed by the previous owner about 3 years ago.

I am trying to loosen the cam screw to adjust the timing, but the screw is stuck. I have applied penetrating oil, and I tried turning the screw almost as hard as I can with the biggest screwdriver I own, but it won’t budge. The screw slot is starting to get mangled from my efforts.

- Does anyone have any suggestions for loosening this screw?
- What is the risk of twisting or breaking something if I find a way to turn the screw really really hard?

Thanks,

Brian Lindenlaub
 
possibly there is locktite on the screw,concentrated heat might loosen it as long as nothing else get will get ruined.
 
Have had that happen a few times. Been successful with using a square-shanked screwdriver with an adjustable wrench on the shank. Need to apply all the downward pressure you can on the screwdriver while turning the wrench. Use a screwdriver that is not loose in the slot. Equally well is a straight-blade screwdriver bit socket with a small ratchet and again put downward pressure. Even a bit for a drill-driver would fit in a 1/4" drive socket.
 
Keep soaking with penetrating fluid, add some heat, then try tightening and loosening alternately with the impact driver.
 
Which FSI distributor do you have?
 

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Take the largest screwdriver that will just sorta fit the slot and grind the sides straight so it fits the slot tight. This is used in many other applications such as the gun trade or carb repair. The normal screw drive with the angled end buggers up the slots when real torque is needed because they fit too loose.
 
Which FSI distributor do you have?

It is a stock Model A distributor with an FSI Electronic Ignition Conversion Kit (6-volt, positive ground). It appears to be an older version of this one, but with an aluminum magnet sleeve that replaces the points cam.
http://www.fsignitions.com/images/kit_pic_fave_sized_for_website_179x135_727i_fz24_t2mu.jpg

I tried using a very large freshly-ground screwdriver yesterday without success. The screw slot is getting pretty chewed up. It looks like the next step will be to get out the propane torch.
 
Good Morning...You might consider purchasing a NEW stock distributor from one of the major suppliers... and using it in your car... and then working on the stuck one as you have spare time...it might turn out to have other problems, as well...sort of a shame to have the car out of service for a part that is not real expensive...Ernie in Arizona
 
I don’t think the timing has been adjusted since the electronic ignition was installed by the previous owner about 3 years ago.
I am trying to loosen the cam screw to adjust the timing, but the screw is stuck.

What makes you think that the timing needs adjusted?
Have you checked the timing to see if'n it needs to be adjusted?

Maybe the timing doesn't need adjusting and you're just making work for yourself.
 
What makes you think that the timing needs adjusted?
Have you checked the timing to see if'n it needs to be adjusted?

Maybe the timing doesn't need adjusting and you're just making work for yourself.

Regardless of the current condition of the timing, at some point down the road, and probably on the side of the road, that cam screw will need to be loosened. Much better to do it in your shop than 100 miles from home and in the dark.
 
Regardless of the current condition of the timing, at some point down the road, and probably on the side of the road, that cam screw will need to be loosened. Much better to do it in your shop than 100 miles from home and in the dark.

I hear what you're saying but why should an electronic ignition need to be timed on the side of the road or in the shop? Once set, electronic ignition should not change, unless a distributor bushing or such goes bad. Then you will have more problems that setting the timing.
 
Ruth, probably doesn't need to be timed. My caution is that if you have something that you can't fix easily (and you should be able to) better fix it in the shop because it'll break on the road. Everyone has their own way, that's mine.
 
What makes you think that the timing needs adjusted?
Have you checked the timing to see if'n it needs to be adjusted?

Maybe the timing doesn't need adjusting and you're just making work for yourself.

I am adjusting the timing to correct a condition that prevented full spark advance when I bought the car. The spark control was set up so that moving the spark lever all the way up placed the arm on the distributor in the middle of its range. The timing was set to give 0 degrees advance in this position. The spark lever would advance the spark only in the first 5 notches down before the distributor arm reached the limit of its range. It was as if the spark control rod was too short. To get full range on the spark control I lengthened the control rod by cutting the rod and installing one of those brass dog-bone-shaped spark rod adjusters. It gave me the extra length I needed. Now full range on the spark control lever gives me full range on the distributor arm, as intended. But the ignition is still timed for 0 degrees advance when the distributor arm is in the middle of its range. I need to adjust the timing so spark lever all the way up gives 0 degrees advance like it is supposed to.

Sorry for the long-winded explanation. I hope it makes sense. I really appreciate everyone's interest and all the suggestions you have given me. One of the reasons I chose a Model A is the strong support within the Model A community like you all have given me.

Next I plan to heat the screw with a torch, and then while it is hot have a friend bear down on the screwdriver while I try to turn the screwdriver shaft with a wrench. If that doesn't work, I will try using an impact driver. If that fails, perhaps it's time for a new distributor as Ernie suggested.

Brian
 
If you have access to a welder, buy a 1/8" npt female to 1/4"npt male black steel pipe bushing fitting. Place the 1/4" side on top of the screw and thru the 1/8" weld a little bit. Let it cool then you can take a 5/8" wrench and have a good grip to turn it loose. The heat will do wonders to loosen things up.
 
i agree with others. Take out the distributer and put it in a vice. Put some heat on the screw. If that does not get it take the distributer to a shop with some older mechanic that has worked on A's and pay him 10 bucks to remove the screw.
 
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