Helmet Distributor Rebuild

[Ziggster]

I thought I would document my attempt to rebuild my helmet distributor. There really isn't that much info available out there with the exception of what you can find here, so I'm hoping I'll be able to contribute to the knowledge base. I ordered a bunch of stuff from Third Gen Auto just before Christmas, and it arrived yesterday (not bad IMHO considering I live in Canada). They were great to deal with. A pic of the stuff I purchased with the exception of the pints which I picked up last year on eBay.

[Ziggster]

A pic of the parts from the helmet distributor and the original crab distributor. I see I've already lost some parts. D'oh!

[Ziggster]

I've already bead blasted and painted the housing with some "natural" aluminum engine paint from DupliColor. I also "blued" the cap retaining clips. Forgot to mention, I also ordered the gasket kit from Third Gen Auto (P/N 18-12104-S).

[Ziggster]

First step is to remove and replace the lubrication cap. Should have done it before I blasted and painted the housing. I would have saved it, but the spring was busted.
I guess this is why I should have removed it earlier. Hard to see, but it is filled with crud!

[Ziggster]

This what I could get out. Keep in mind, at the moment I'm posting this in real time, as I go about the rebuild. Haha!
There seems to be some type of fibre type material in there. Note that neither the oil cap or fibre material are shown on the exploded view!

[Ziggster]

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Exploded view.

[Ziggster]

A bit of touch up paint around the opening, a few taps with a plastic mallet, and new oil cap is installed. Onto the guts...

[Ziggster]

I purchased a "new" 11A shaft to have a bit more range in the timing. A comparison of the two shafts.

[Ziggster]

Now this looks a bit mangled. Did I say as a mech eng, I'm great at taking things apart, but not so great at putting them back together? As I get older, I get worse. Lol! Thank God we have the ability to take pics, and I mean lots of pics, maybe too many pics.

[Ziggster]

Time to reflect on how this puppy goes back together...

[Ziggster]

This looks about right. Will straighten and clean contacts. Left looks good, but there is a bit of corrosion? on the right one. Using 600 grit sand paper.

[Ziggster]

Starting to make sense...

[Ziggster]

Geeeze these springs do not look the same. Came out of the box like this. I'm guessing the one on the left is how it should be.

[Ziggster]

The inner springs do not feel like they are the same. One seems thinner/weaker than the other, but the originals are the same. Am I imagining this? If they are different, which goes where?

[Ziggster]

More assembly...

[Ziggster]

Onto the shaft. Advance weights installed.

[Will D]

Originally Posted by Ziggster

The inner springs do not feel like they are the same. One seems thinner/weaker than the other, but the originals are the same. Am I imagining this? If they are different, which goes where?

The outer is the spring. Inner is just a copper strip to ensure current flow.

[Ziggster]

Plate and spring clip.

[Ziggster]

Cam rotor clip installed.

[Ziggster]

A bit of oil on rear bearing, and install into housing.

[Ziggster]

Sorry, forgot to attach pic...

[Ziggster]

Point plate installed with retainer spring/clip. Now I guess, I need to set the gap. Off the top of my head, I can't remember what it was, but I think it was 0.014?

[Ziggster]

Something is not right. I hear clanking and the "advance" plate is loose. I think someone once mentioned a washer, and not to lose it. I have a flat washer for the crab, but not the helmet. Did I lose it? D'oh...

Crab washer.

[Ziggster]

I also installed the helmet advance plate and not the 11A advance plate from the crab. Damn, those retaining clips are a bastard to get off.

[Ziggster]

Originally Posted by Will D

The outer is the spring. Inner is just a copper strip to ensure current flow.

Ok. Thanks.

[Ziggster]

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Time for a break/ lunch. There was a little brown envelope in the FoMoCo points box. Of course, it is missing the cotter pin. Haha!

[Ziggster]

There were also instructions neatly folded up. I was about to toss it thinking it was garbage.

[Ziggster]

"Second" page...

[Ziggster]

Replaced the advance plate with the one from the crab. Fits much better although I couldn't even get a 0.006" feeler gauge between the retainer ring and the helmet advance plate. Remember when I said maybe I took too many pictures? Well, the pics I took of the disassembly as well as others have "disappeared". I think it is because my memory is almost full with over 9,000 pics. I found a snapshot I took off of someone rebuilding a helmet distributor in the interweeb, and there didn't seem to be an "extra" washer. I think that washer is specific to the crab style. Back on with the show. Haha!

[Ziggster]

Adjusting the gap. The 1950 FoMoCo instruction sheet said 0.015", or between 0.014" and 0.016". Gap set to 0.15".

[Ziggster]

Rotor installed. A bit of oil on the other shaft bearing.

[Ziggster]

Guts installed in distributor housing.

[Ziggster]

Interior caps installed. One needed a bit of persuasion.

[Ziggster]

Other side.

[Ziggster]

Oops. Forgot pic again.

[Ziggster]

I think Bubba mentioned using Mobiil 1 grease on the vacuum brake cylinder. I don't have any, so I used some Lucas NL GI grease that I had lying around.

[Ziggster]

Vacuum brake tube nut loosely installed as well as brake plunger spring retainer nut. Don't forget the washer...

[Ziggster]

Washer with center hole visible to align with adjustment screw.

[Ziggster]

Adjusting screw with locking nut installed. I have no idea what pressure or tension is needed.

[Ziggster]

Ignition coil gasket. That was tough. Lol! Much thicker than the original. I wonder why?

[Ziggster]

Gasket comparison.

[Ziggster]

Ignition coil installed.

[Ziggster]

Timing adjustment plate and hardware. The crab one came with a lock washer, so I'll use, but need to clean off the rust.

[Ziggster]

Not sure again where it should be for initial startup.

[Ziggster]

Condenser coil installed. Had to remove the ignition coil as the screw to attach the condenser coil cannot be accessed once the ign coil is installed. Be careful not to loose the carbon brush and spring.

[Ziggster]

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Exterior caps and extension boots installed. They forgot to send me the ones I ordered, but since I now have a brown coloured coil, I'll get some used brown ones from them to match.

[Ziggster]

The new coil didn't come with the wire connection nut, so I'll use the original one. I'll clean up a bit of the hardware, but that's it folks. I say that's it, but it really isn't as there are further adjustments needed to get things working their best that require special equipment. Yes, you can do the field adjustment, and perhaps it is ok, but not optimum. I will say this was a great learning experience, and hope it helps those willing to tackle something like this. Would i recommend this to everyone? Simple answer is no. It is a lot of work to clean and prep the housing. Actually, when you factor the time, cost of materials, etc, what people charge to rebuild this is actually very reasonable IMHO. Another reason I wanted to pursue this on my own was also the exchange rate between the US and Canadian dollar, which easily adds another 30%-40% to the cost, plus the shipping, duty, etc.

[doghair3]

My Helmut Distributor works just fine but this makes me want to go out and get a clunker and tear it apart just for the hell of it. Nice job.

[FRANK PKNY]

Nice job I just set the points at .015 seems to work for me well.

[Ziggster]

Thanks. Fairly easy to assemble, but it is all in the prep work like most things in life. Actually forgot to open the envelop of gaskets. Lol! So it is not "done"! Haha! Will follow up later after I've cleaned up the hardware, and polish the end caps.

[Zeke3]

Ziggster, have you heard of the modification to put heat shrink on the shaft, under the rotor to prevent grounding from the rotor to the shaft?

[marko39]

Originally Posted by Ziggster

Condenser coil installed. Had to remove the ignition coil as the screw to attach the condenser coil cannot be accessed once the ign coil us installed. Be careful not to loose the carbon brush and spring.

Save yourself future grief and notch the condenser ground so you don't have to remove the bolt to change it. You can just loosen it a couple turns.

[Ziggster]

Originally Posted by Zeke3

Ziggster, have you heard of the modification to put heat shrink on the shaft, under the rotor to prevent grounding from the rotor to the shaft?

No. First I had heard of it. How can it ground to the shaft?

[Ziggster]

Originally Posted by marko39

Save yourself future grief and notch the condenser ground so you don't have to remove the bolt to change it. You can just loosen it a couple turns.

Good to know. It is a bit of an ackward design in terms of RR.

[Ziggster]

Just a quick follow-up. There is so much info out there (here and on the HAMB) about flathead timing it is almost overwhelming. Anyways, after some more reading and review, I've set the adjusting screw for the vacuum brake at 1.5 turns in, and the adjustable timing to 3rd mark from bottom which I guess equates to 4 degrees of advance (crank).

[mercman from oz]

Ziggster, From Parts to completed Distributor.
Thanks for the pictures and hints on rebuilding these Early Ford Dome Type Distributors.

[Zeke3]

Ziggster, check out post #49 in the attached link regarding wrapping the center of the shaft with some material to prevent leak paths from the rotor.

https://www.fordbarn.com/forum/showt...ht=heat+shrink

[35fordtn]

Ziggster, Given you have a NOS rotor the insulation around the shaft wont be to much a concern. Ford had a service bulletin, as the rotors after use can crack on the inner portion and short out to the shaft. MAny rebuilders such as myself install electrical tape or shrink wrap over the shaft to prevent a occurance.

[Lawrie]

and you need to set the points with the assembly installed in the housing, coil on and adjustment screw tightened
Lawrie

[Ziggster]

Originally Posted by Zeke3

Ziggster, check out post #49 in the attached link regarding wrapping the center of the shaft with some material to prevent leak paths from the rotor.

https://www.fordbarn.com/forum/showt...ht=heat+shrink

Thanks. For the link. More great info I somehow missed.

[Ziggster]

Originally Posted by Lawrie

and you need to set the points with the assembly installed in the housing, coil on and adjustment screw tightened
Lawrie

Thanks. I see now why all this matters. After watching the great vid on the Sun tester, I'm even more motivated to see if I can get my Allen one working.

[koates]

Originally Posted by Lawrie

and you need to set the points with the assembly installed in the housing, coil on and adjustment screw tightened
Lawrie

Lawrie, very important point. Once all is assembled with the timing plate screw tightened and the coil mounted and tightened down then the points plate will move slightly and upset the contacts gap. The points gap is done last and usually done on the bench timing fixture or on a SUN machine for a running test. Otherwise just set both sets at .015"and it will run Ok. Access is through each side cap opening before caps and leads are fitted. I suggest that you find a bench timing fixture to set up the distributor before fitting it to the car. If you dont do it that way then your contacts can end up being set to what knows gap. Also tighten down the vacuum brake lock nut with about three threads showing on the bolt for a starting position. Final adjustments can be done by driving the car. Regards, Kevin.

[Charlie ny]

Steve,
Regarding post #15 did you check point alignment ? This is the time to make sure the contacts close square. With the breaker plate fully assembled aligning the fixed arm to the movable arm is easily done. In your post #21 it's not a bad idea to check the wear between the rotor shaft and bushings.....usually the small front bushing is OK....I find however the big rear bushing is usually worn excessively as is the companion diameter on the shaft. Running fit seems to work well at .001 between the shaft and bushings.
A great presentation !
Thanks,
Charlie ny

[Ziggster]

Thanks again for all the pointers. I don’t think I’ve set points since the mid 80’s when I had a 71 Skylark, and 78 Firebird. Lol! I was wondering about that. They seemed to line up ok before I installed it into the hsg. The PS side looks good, but the drivers side looks to be slightly out alignment (movable side maybe a couple thou too high), but worse it doesn’t look the points are fully closed on the DS.
On the issue of the shaft, both this shaft and my orig one fit nicely with no discernable wear, but a thou is pretty hard to “feel”.

Can’t upload pics again, but will try later.

[Keith R]

thanks for this thread. I'll be doing one of these in the future.

[Ziggster]

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So after cleaning up the hardware, I disassembled the distributor. I can confirm that the DS points were not closing all the way. Just goes to show how things move after installation. I reset things again, and all seems fine, but again that is before installation into the housing.
I also forgot to apply some lube to the cam. I should have remembered to do so, as the original from my crab distributor was badly worn. I have some Valvoline Special Moly EP which I use on the knuckles of my truck. I'm hoping the moly will help things stay put. I saw some Lucas Red "Slip n Slide"? this morning at the auto parts store, and thought it would be good to have some, but never purchased it. Only if I had known then I could have used it for perhaps this application. I also put a bit of the moly grease on the shaft bearing surfaces and on the interface surface of the inner and outer housing at the rear to help dissassembly in the future.
The alignment of the points look good, and I'll recheck when it is time to run the engine. Unfortunately, I'm having storage issues on my iPad, and I deleted all those pics, but here is a pic of the gaskets.

[V8COOPMAN]

divers helmet

[Bored&Stroked]

Good job Ziggster . . . yah did it! Thanks for putting this journey together - may help somebody else who is heading down the path.

[Terry,OH]

With the coil off and inner caps on, you can see how close the rotor contacts are to the cap contacts and if they align properly. There is a thin washer to put at one end of the rotor to remove end play and to center the contacts. I use a couple of wraps of good electrical tape (Scotch 33) under the rotor, each wrap of tape is good for 1,000V shrink tube is no where near this electrical rating.

[fortyonerag]

Ziggster,

Many thanks for the thread. I'm just about to embark on this work and there are many useful tips here.

Sending it out for a rebuild is an expensive and time consuming exercise from down under!!!

[Ziggster]

You’re welcome. Not that I’m any expert, but if you have any questions feel free to send a PM. I feel it is very important to share as much as we know.

[FlatheadTed]

Some years ago I think in Shellys time . I posted that I got stoped on the road with a orignial 34 v8 it would not pull up a hill, badly missing engine ,
I only had a pair of pliers and a screw driver and tape I managed to get the Distributor of I had worked on it prior and figgerd it had to be the roter shorting through to the shaft ,I had a brain wave I thought if I wrapped this tape around the shaft I might get it to work ,It did and i got home no problem ,you can see the wrapped shaft in the left of the picture . ,Ted

PS Good post by Ziggser

[Chill]

How do you file the inner distributor cap contacts so they have the proper gap from the rotor? I assume its done through the opening where the coil mounts. But I haven't taken it apart yet.