SD Baseplate timing screw

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NaughtyBits
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Joined: Fri Apr 17, 2015 6:30 pm
Location: Bermuda

SD Baseplate timing screw

Post by NaughtyBits »

Hello all,

I'm rebuilding an SD & SDP that I picked up incomplete and needing a whole lot of love. Making good progress so far with what I do have and with sourcing bits I'm missing, thanks to a few of you here on the forum (I'll keep an eye out for opportunities to help out in kind or pass on the kindness). I'll also post some before & after pics on the General page soon and get the info to ? (Sorry, I can't remember right now who it was who's collecting info for a database - I'll look again)

I'm finding some of the threads a little damaged and/or in need of enough of a clean-up that I'll be sourcing a few taps. Can anybody confirm whether the base plate timing screw is 5/16 (26tpi) brass/pipe or cycle thread? One has a 55 degree pitch, the other 60.

Likewise, I've been able to sort out the 1 ignition (now getting a strong spark) - but no such luck with the second coil. I've found several posts re: John recommending George doing a rebuild, a few posts re: using new a smaller replacement coil from Villiers that needs to be sleeved up and a few posts re: the replacement coils available through Green Spark Plug (GSP) Co.

Has anybody had much luck with the Villiers replacement or with using the GSP Co. coils?

Interesting differences on the SD & SDP so far - 1 has a base plate with no inner clamping ring & 1 had an alternator fitted, extra coils wrapped on each long coil retainer laminates...

Thanks for your time,

Jason
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NaughtyBits
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Re: SD Baseplate timing screw

Post by NaughtyBits »

Also, I'll need to make new washers either side of the tiller arm (also missing) - were they originally rubber, fiber or something else altogether?

Thanks again,

Jason
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Charles uk
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Re: SD Baseplate timing screw

Post by Charles uk »

Charging coils seem to have been on the Marston part list but not the SD list, could we ask you for the JM numbers from the flywheel & base plate of that ignition, that should enable us to deduce whether this is a pre or wartime ignition.

Up to this point in time I don't believe anyone has worked out what the "P" in SDP actually signified.

It's not usually the thread that's the problem on the clamp screw when it won't turn but aluminium oxide in the parallel bit before the thread.
Make it idiot proof and someone will make a better idiot.
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Oyster 49
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Re: SD Baseplate timing screw

Post by Oyster 49 »

SOS can supply the washers to fit either side of the tiller, as well as the rubber bush that goes inside. Can you post some pics of the charging coils please?

Also I've used Green Spark Plug co for several items have all been fine, I've never used their coils, but I suspect they all come from he same place. George at Villiers parts is also good. He can strip and rebuild the whole magneto if you wish.
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NaughtyBits
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Re: SD Baseplate timing screw

Post by NaughtyBits »

Thanks Uncle Charles,

Here are the numbers:

SD 5366L3
Flywheel # - JM 8315
Baseplate # - has been milled out to fit the steel inner ring so that only the top 1/4 of the numbers are visible, too little to know
Ignition - 'Long arm' laminates, fitted with alternator coils, points are the older nut adjustable variety in brass casing
Clutch, shortshaft, zinc (?) plated drive tube
Ministry stamp on skeg

SDP 8806LX
Flywheel # - JM 121697
Baseplate # - has been partially gouged out, so that middle numbers are unclear. Best guess - 1706 on one side, 1137X4 on the other - no inner ring
Ignition - 'Long arm' laminates, points are the older nut adjustable variety in brass casing
Direct, longshaft, chrome plated drive tube

Re: timing screw - there's definitely thread damage halfway down, the first non-threaded 1/2" is clear. So I'll definitely need to re-tap - I just didn't want to assume the 5/16 26tpi screw's thread pitch was 55 degrees (same as BSF) and not 60 degrees (as British Cycle).

Aside for missing the usual rare bits (carbs, tanks, one prop) both motors seem to have been tinkered with in the past (thrust washer missing in gearbox, points not set up correctly, new wider oil nipples fitted, etc).
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NaughtyBits
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Re: SD Baseplate timing screw

Post by NaughtyBits »

Thanks Oyster 49,

I do have it on my list to call John about a few things for other motors, so I'll check. I've managed to clean-up and repair the inner rubber bushings. I also have similar sized rubber washers (for either side of the tiller arm) from another project that I can trim to fit - I was just wondering if they were originally rubber or some other material, as they were missing when I got the motors?

I'd heard George may no longer be able to source the correct coils? So I thought I'd follow up with those that have tried other alternatives (sleeving up a smaller coil from Villiers, Green Spark Plug coil, etc) to see if they're still performing well?
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NaughtyBits
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Re: SD Baseplate timing screw

Post by NaughtyBits »

Baseplate on the SD
12654252_10153901155297813_7279579452288520507_n.jpg
SDP Baseplate on the left, I've cleaned up & repaired - now has a spark
12573085_10153901155292813_28366359626255018_n.jpg
Obligatory workshop pic - Charles. it's gotten a bit messy since your last visit..
12645249_10153901155307813_4074587502693642335_n.jpg
Current flock pic (daughter's motor on the right, son's in the middle - which my wife currently races until he's old enough, my father's & my race motor on the right) - Hoping to add the SD & SDP to similar usable condition...
12631284_10153901157317813_5213377864450516103_n.jpg
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NaughtyBits
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Location: Bermuda

Re: SD Baseplate timing screw

Post by NaughtyBits »

Well after more searching, I did find my answer re: fixing screw thread from Uncle Charles UK in 2006

"There are some notable exceptions like the magneto base plate locking screw which is British Standard Cycle Threads." - Charles UK.

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