Mks 2 and 3 ignitions voltage

[Donald A]

Can anyone tell me the output voltages for the above?
I have just bought the bit in the photo and one alters the gap according to the voltage
Also the Button on the end unscrews so you can put a spade end onto an m4 screw
Yes I know I can do it the old fashioned way but this looked better
Donald

[Charles uk]

I thought that was the purpose of these devices, that you set the gap small, test you get a spark, open the gap in increments until no spark, then return to the last setting where there was a good spark, should gives the voltage at starting revs, I think you'll find a chart in the instructions giving of the voltage required at various gaps.

[Horsley-Anarak]

Can anyone tell me the output voltages for the above?

Most spark plugs need between 12,000 and 24,000 volts to spark.

Can be as high as 40,000 volts.

Why do you need to know the voltage?

I usually find that all seagull ignitions work or do not work, I have worked on most of them, main issues are dead coils.

Do you have issues with coils or CDIs?

[Donald A]

Thank you both so very much for the missing logic and info that makes it all crystal clear
Hopefully photos attached (having size problems) that show instructions (which don’t contain Charles’s essential logic at all) and the EF and the 1969 mk 2 featherweight
I got completely the wrong end of the stick and thought I needed the voltages first to set the adjustable gap....
The EF went very smoothly ( having started from a cracked cylinder and totally seized steel studs) and now works very well
I expected the same with the mk2 - the coil was refurbished by Sheridan sending it to their (probably retired) Wipac specialist and the points were NOS ... the coil gives about 4900 ohms at room temperature .... and the ht lead, plug cap and plug all have continuity, so when I can get back to spending time on it, I shall have to work through it on first principles - again! Right now it’s on hold because of other essential lockdown
tasks eg meals, sanitising deliveries etc etc
Thank you both again - keep safe in this difficult situation of so much misinformation....and the price of ffp3 masks mean I now understand what my old man’s tone of voice meant when he talked of a war profiteer...
Donald

[Donald A]

More photos - instructions and EF
Donald

[Donald A]

Bigger photos - it would be interesting to know the size thresholds for photos applied by this web site....
D

[Horsley-Anarak]

Wow your motors are in great shape, what sort of boat are you planning to use them on?

[Charles uk]

Interesting fuel taps where did they come from?

So if it sparks at A can we assume 10 KVA, if B = 20 KVA, C = 30 KVA, 40 KVA, isn't that what I implied?

Most owners don't fasten the throttle cable to the tiller arm as you run the risk of kinking the cable outer.

[Donald A]

HA that is a very kind and generous comment, if I may say so, which I value greatly, having seen your photos of what you do! The only thing that still doesn’t look right is I couldn’t get a proper gloss on the black tank - I tried a large number of sprays with clear from the local automotive supplier but it didn’t work- perhaps I was too tentative about not putting it on too thickly in case it might run - which on a smooth surface it does only too easily ....
My 23 foot plywood cruiser (Robert tucker stretched his well known 19 ft caprice to 23 ft)
had to go, so I now only have an inflatable...much to my chagrin
Charles - That is exactly what you implied, which is why I used the words “crystal clear” and “essential logic”.....interesting that you suggest 10 K for the first mark, where it is silent - that assumes it’s linear?! The centre long screw is 1/4 BSW 20 tpi (which surprised me) but is very loose in its thread- waves around about 2-3 mm at its point, so fingers crossed as to how well it performs
D

[Donald A]

Oh and I missed out that the Petrol tap comes from George at Villiersparts - sorry about it not being original, but I wanted something that would not leak, looked ok, and had that rather unusual thread on one side, for which I could not get a tap or die....
I also put a longer screw at the bottom of the drive shaft leg, with a locknut on it- after all it’s all there is to stop the whole lot dropping off!
D

[Horsley-Anarak]

so I now only have an inflatable...much to my chagrin

Could be time to make a small plywood boat, have had great success with the ones I have made.

Now my kids are showing interest, will be designing another easy to make boat that will be car toppable, and propose to make 3 early summer.

Will be posting progress on the forum, will be similar to this one but slightly bigger.

[Gannet]

Donald,
I have picked up your comment about Robert Tucker stretching his Caprice to 23 ft. What was the 23 footer called? I use to own a Robert Tucker Debutante. That was 21ft and a truly excellent cruising boat. He really understood how to design a boat for plywood construction.
Was the next size up called an Escapade?
Sorry to have drifted off the topic of ignition.
Jeremy

[Donald A]

Was called a Capriccio 23
Not many were made - it came out in the mid sixties, by which time grp small boats were getting into their stride
Had twin forestays, twin backstays, and either fin or bilge keel. Mine was fin. Reverse transom
Being one of his last designs, he had the balance problems of a hard (single) chine boat sorted, so it went fairly quickly to gunwhale awash, but still perfectly balanced on the helm - unlike a silhouette I sailed once, which had horrendous weather helm
It’s only real problem was a low ballast ratio- I never found out how much of the 1 ton displacement was in the keel, but it used to wave from side to side very quickly on a swinging mooring when ships passed by, and was tender to sail. I was told it was intended for JOG racing which might account got that.....
The problem I found was that the cascamite glue became brittle when old and the wood panels began to come apart....
On another point thank you for the suggestion of V ring seals (if I remember that correctly) which work very well on the prop shaft and have virtually stopped the leak - brilliant
Keep safe
Donald

[Gannet]

Donald,
I haven't come across the Capriccio 23. Tucker was very productive, with many designs to his name. My Debutant was also heavily rigged with twin forestays and twin backstays. In an era of hanked on jibs, the twin forestays were a boon for sail changing and for setting two jibs downwind. The Debutant was also a JOG design with a 16ft (or was it 16.5ft) waterline. It exhibitted weather helm if pushed too far, but by keeping weight out of the big stern locker the effect was significantly reduced. Happy simple times! The Debutant was a truly excellent and safe family boat.
I am glad that you are pleased with the performance of the V rings on the propshaft. Simple, but effective.
Jeremy

[Donald A]

This thread was left unresolved, so here is what happened
The problem was that I could not start the restored 1969Featherweight .
I built a test bed from a base plate and coil and flywheel so that I could actually see the spark - driven by a battery drill on the top of the flywheel which meant I could replicate slow speed for a pull cord start, and a higher speed for normal running
It became apparent that the spark on low speed was very weak and small and intermittent - whereas it got much better at higher flywheel speeds
I then found a guy who could increase the windings on the secondary coil, thinking this would produce a higher voltage spike - he increased the number of turns by about 1500, and when it came back, the ohms reading on ht to ground was 7130 ohms at about 20degrees c - he couldn’t do more because of the constraint of the size of the coil housing
The engine even then would only start if I injected naphtha (engine start) after which it ran well and evenly
I then rang Ngk spark plug technical advice and explained the above . The guy there said you are in a similar position to my customers who run 1920/30 classic cars, which have to be started with a crank handle ie a slow hand start
He pointed out that iridium plugs will spark at a lower voltage than others - so try that . He also said the match to the champion d16 or Ngk ab6 would be more easy to get if I put in a plug adaptor that brought the 18 mm plug hole back to 14 mm, because there is a greater choice of iridium plugs in the 14 mm size. Also it has to have a squash washer, not a bevelled edge, above the thread.
The plug adaptor means that the iridium has to have a longer reach - so he specified Ngk BPR6EIX
These are now fitted - and I am very pleased to say it works! I can now start it at pull cord speed
I realise this is not how it should be, on the other hand if it works it works! Plug photo attached
I hope this helps a first timer with mk2 starting problems - any comments?
Donald