Upshur's opposed twin engine

[Steamchick]

Capacitor must be matched to the coil, or you can lose sparks inside it or just get all the sparks at the contact breaker!
Take care, High voltage can make you jump! Old hearts don't like it.
K2

 

[werowance]

well, im using just a plain old generic ford style coil. old school style with external ballast resister inside my portable ignition unit (old ammo can with battery, coil etc inside it. coppied said idea from Brian R) but the capacitor is a small one.
the plans for the Upshur Vertical Single calls for a .2 or .3 micafarrad rated for 300 or 400 volts. what i used was Panasonic ECW-FA2J224J .22 @ 630 volts that Roy Sholl provided and worked great for me.

post 307 in my build below of the single.
https://www.homemodelenginemachinis...attempts-upshur-vertical-single.31677/page-16

 

[Brian Rupnow]

Thanks for the link Werowance--That is a great running engine.---Brian

 

[Brian Rupnow]

I'm doubting my ability to successfully solder ignition points onto the brass strip as per the engine plans. However-- If I move the flywheel out farther away from the side of the crankcase and switch the ignition cam to the other side of the engine, there is lots of room for my purchased Dodge ignition points. I've been a bit under the weather for a few days, so I haven't done any work in my shop.

 

[Steamchick]

Take it easy but get well soon.
K2

 

[werowance]

Brian, maybe i just got lucky but i just used a soldering iron like i would for general electrical work and an old roll of electronics solder. same stuff i use when fixing the wiring on my old trailer and such. it stuck great for me, hardest part was holding my hands steady while holding everything

 

[gbritnell]

The problem is they have to operate off the camshaft, not th crank.

 

[Brian Rupnow]

No George--Not on this engine with dual cylinders. The points operate off the crankshaft no matter which side they are on. The points open every time the crank rotates thru 360 degrees. The distributor selects which cylinder the spark is going to.----Brian

 

[gbritnell]

So a waste spark for both cylinders?

 

[Jasonb]

No

Crankshaft comes round and trips the points, single spark travels through the distributor to one spark plug

Crankshaft does another 360deg and trips the points again but this time the camshaft has rotated 180deg so the other contact in the distributor now sends the single spark to the other cylinder's plug

 

[gbritnell]

I forgot the engine was using a distributor. Probably would be just as easy to use a waste spark and do away with the distributor all together

 

[Brian Rupnow]

So, here we are with the ignition cam and the purchased point set mounted on the flywheel side of the engine. The flywheel shape will change, so that an extended outer diameter will cover the ignition points so that they won't be visible when all is assembled. Please note that the engine hasn't been "cleaned up" for any of these "in process" pictures. Before the engine is finished and running, there will be a big "clean up" before any finished pictures are shown.---Brian

 

[olf20]

So, here we are with the ignition cam and the purchased point set mounted on the flywheel side of the engine. The flywheel shape will change, so that an extended outer diameter will cover the ignition points so that they won't be visible when all is assembled. Please note that the engine hasn't been "cleaned up" for any of these "in process" pictures. Before the engine is finished and running, there will be a big "clean up" before any finished pictures are shown.---Brian

Getting closer. Can't wait to see her purrrrrrrrr.
olf20 / Bob

 

[Nerd1000]

I forgot the engine was using a distributor. Probably would be just as easy to use a waste spark and do away with the distributor all together

You'd need a double-ended ignition coil, but those are easy to find as they're used in all kinds of small 2 cylinder engines.

 

[Jasonb]

One of the reasons Brian went for this engine is because he wanted to make one with a distributor. Go and read the first couple of lines of post #1

 

[mrehmus]

I find those small ignition coils used on Ford engines to be fairly small and very effective and low cost from eBay.

 

[Brian Rupnow]

Now isn't that a beautiful thing!!! The new flywheel and hub fit into place exactly as I had expected, and cover up the ignition points. I still have to figure out where I am going to put the condenser, but that can be tomorrows work. Today I have been fighting with horrible weed eater machines, and think that with shop labor rates being so high now that I am farther ahead to buy a new one than to have the old one fixed.---Brian

 

[Vietti]

I know as an engine builder it is embarrassing not to be able to get a weed whacker to run. I have had some luck replacing the carb with a cheap replacement from China

 

[Brian Rupnow]

My weed whacker runs---it's the other end that has something gone wrong. I could fix it---but---at 77 years old, I choose my battles carefully. I play with small engines as a hobby because I like to. I don't do maintenance on my car or truck, nor on my gardening equipment. I could--but thank the Good Lord the Rupnow fortune is sufficient to let me work on only the things I now enjoy.

 

[Nerd1000]

My weed whacker runs---it's the other end that has something gone wrong. I could fix it---but---at 77 years old, I choose my battles carefully. I play with small engines as a hobby because I like to. I don't do maintenance on my car or truck, nor on my gardening equipment. I could--but thank the Good Lord the Rupnow fortune is sufficient to let me work on only the things I now enjoy.

I think your policy of picking your battles is a good one. I'd much rather be using my limited mechanical skills on something fun in the shop than crawling under my car, getting covered in dirt and scuffing my arms up trying to remove a faulty alternator pulley... which is the position I found myself in not long ago.

It's a pity that so much modern equipment is effectively 'throw away' stuff that's more costly to repair than replace. Seems crazy that in a world where we are all worried about pollution and CO2 we would rather build a whole new weed whacker (or whipper-snipper, as we call them here) than design it to be easy to fix. But that's another story I suppose.