90 degree V-twin engine

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Thanks everyone. Chuck, I'm just finishing up the ignition. Today I got the Hall transistor wired and epoxied into the notch in the timing cover. I then took the whole thing apart. I needed to drill the motor mount pads on the engine and drill and tap the stand. I also decided to put a tapered pin through the crank cheek and pin on the flywheel side, just to be safe. I have a few other small items to take care of with the crankcases split and then I'll start putting it back together, this time for good. I'm looking at trying to start it somewhere around the third week of the month. I'll definitely post a video when I try to start it.
George
 
Amazing workmanship George.

This thread is very educational for us hobbyists,
thanks for a great learning adventure.

Very nice design...
Beautiful engine... :)
 
The engine got torn down. As I had mentioned I pinned the crank with a tapered pin. I added an oil level plug to the side of the crankcase. I put the mounting holes in the crankcase and base. I made up a dummy shaft to run the oil pump to check it out, it puts out plenty of oil. I gapped the piston rings and installed them on the pistons. I made up gaskets, cleaned all the parts up and reassembled it.
After putting it all back together I chucked the crank in my lathe and starting off at slow speed and ran it for about 1/2 hour. I then increased the speed a little bedding in all the parts and rings. I didn't have the magnet put in place in the timing pocket and the oil came pouring out of there while I was running it. I jammed a piece of wooden dowel in the hole while I finished putting some time on the engine.
Over the years I have bought numerous ignition systems and every time I buy one I always buy an extra magnet or two. The problem is I didn't mark which was the south pole on them. The Hall effect transistor will only work off that pole. I have some extra Hall transistors so I added leads to one and hooked it to my ignition system to check everything out and mark all of the magnets (6) properly.
With that done I epoxied the magnet into the timing cover and while I was at it I filled the drain back hole that I had thought I would need. If some oil gets in there it won't hurt anything and I can always take the cover off to wipe it out.
Another 1/2 hour or so of running in on the lathe and I'll finish mounting the intake manifold and carb. I
I have to add another post on my ignition box for the second plug wire. The last coil I bought from Jerry Howell was the dual lead one, how fortunate, the don't sell them any longer.
It looks like sometime next week it'll be ready to run. Now I'm really getting excited.
I'm attaching several pictures of my timing disc and Hall trigger setup. You can see the magnet through the window in the disc.
George

OJ.jpg


OK.jpg


OL.jpg
 
I can't wait George. Hurry up will ya!

If you have a compass you can tell the South pole easy. North needle is south poled. Take the magnet and .....well you know where I'm going.

Tony
 
Gosh, it just gets better and better every time, I think that I will have to go and throw rocks at my junk ;D I haven't been around the hall effects much, I tried it on my hit or miss on the valve push rod and had the magnet slide past the pickup, it would not work and kept causing the pickup to fail, the fellows who made the ignition box did not know why and said that they had never had a pickup fail, I went through three or four and got tired of having to solder them. I went to points and everything works well but they are still the weak link in the engine with the open crankcase. I like how you use the interrupter plate for the timing, What are you going to do for a distributor ? Thanks; Tad
 
George,

I'm with Tony, can't wait for the V- Twin sound!!!

What a Master Piece :bow: :bow: :bow:

Jeff
 
While bolting things back together and fooling with the ignition I realized that it would be beneficial to have some timing marks. There wasn't much available space around the flywheel except at the front of the engine so I made a reference pointer from .032 stainless steel and bolted it to the motor mounts. I then put a tap in the spark plug hole to run the piston up against to get TDC. I first marked it in one direction and then the other. With the two marks I split the difference for the true TDC mark.
I then put my newly made high speed spindle to work and cut the reference lines, one at TDC and every 5 degrees up to 30. Most of my small engines have never needed more than 30 degrees, generally 10-15.
As a side note, at one time I had purchased a set of stamps from Harbor Freight, don't bother. I decided to get a good set and when Enco had a Young Bros. set on sale I bought one. These are 1/16th stamps. I set up guides as best I could but they didn't come out perfect. After looking more closely at the stamps each one varies just slightly from the squared edges of the stamp body, Oh well! Anyway here's the results.
George

OM.jpg


ON.jpg


OO.jpg
 
This is what it looks like cleaned up with the scribed lines darkened and mounted on the engine.
George

OP.jpg


OQ.jpg
 
George, I have a hard enough time getting nice decent numbers without having the stamps being defective!
I've been though the far east route with stamps. Some things, they make well, some things, definitely not.

Every time I see another post with your name, I'm thinking "maybe there will be some sound!".
Yes, I'm pretty excited to see it run.

Dean
 
Well it looks like tomorrow or Saturday for the first start up. I modified my ignition box by adding four more plugs, one for the extra spark plug lead and three for the Hall trigger wiring. I am using this box as a multi-purpose box as I don't want to buy yet another ignition sysem. This way I can use it for a points set up and a Hall trigger also.
I made up plug wires with boots made from vacuum fittings and the wires are from the local hobby store. They're the battery pack wires for RC cars.
For you that have followed the build you can see from the picture of the timing pocket that I made a brass timing disc. Well brass doesn't work. When I hooked everything up and switched the power on my indicator light came on signifying that there was power to the ignition but when I rotated the engine the light never went out telling me that the Hall sensor was still getting a magnet signal. I am using a .125x.062 magnet (very strong). I took the timing cover off and ran a spare magnet across the Hall sensor and it worked fine, firing both plugs simultaneously. I then took the timing disc out and layed it on the Hall sensor and ran the spare magnet over it, the magnetism goes right through the brass disc. I then took a piece of aluminum and tried it with the same results. Only one material left, steel, so I got a piece of .025 steel and set the magnet on it then set it on the Hall sensor, no signal, great.
I then machined a new timing disc from steel and bolted it in. Not knowing at what point the Hall would trigger I just set the crank on about 15 degrees and rotated the timing disc until the magnet was just about covered. I then screwed the cover back in place, turned the ignition on and rotated the engine. When the crank was at about 50 degrees the indicator light came on. As I continued to rotate the crank when I got to about 12 degrees the light went out and the plugs fired. Eureka!!
Tomorrow I'll rig up some type of fuel supply and give it a try. I hope the gremlins are all on vacation while I give it a go. We'll see.
I'll keep everyone informed of my progress.
George
 
I'm anxious to see it, George.
Pretty sure the gremlins will leave you alone, since they are all at my house right now.

Dean
 
No pressure, George, but ya got a lot of people hanging on this... Hope it starts right up.

Chuck
 
Hi George
Looks like start-up day is here soon.
I'm curios of how it will sound. In my opinion every engine have its own specific sound/ beat :)that's create music in my ears.
BTW, George your building log on the V-twin has been a real inspiration for me,and others here at HMEM. :bow: :bow:

CS
 
George,

Why is it the brass disk will not work? Not quite understanding this. Can you enlighten us?

I'm anticipating your first run :) :) :)

Jeff
 
Hi George. You'll geter running. Every one of your engines runs, and runs well!

I would invite my self over to be the first one to see your beauty running

But I don't want the entire forum to be jealous. :big:

-Rick
 
Best of luck with that AWESOME build start up George!.....Were pulling for ya!

I am in awe every time you post George...I have learned a great deal from you...thank you!

Movies please!...... ;D
 
Hi Jeff, I don't know in scientific terms why the brass won't work. I'm assuming that the magnet is so strong that the Hall sensor gets a signal even through the brass. I think the reason the steel works is because when the disc is covering the magnet the magnetism is spread out through the steel and therefore there's not a strong signal focused at one point. If anyone out there is more versed in this area please add your two cents worth because I would be interested also. All I know is if you're going to use a stationary magnet with a window timing disc, make it out of steel. Most people who use a Hall sensor for timing mount the magnet on a rotating disc, cam gear, flywheel etc. and have the sensor stationary so it's not an issue. On this engine I didn't have the room to do that so I went with the automotive type control.
George
 
Rick, I'll give you a call when it fires up and you can come over and see it.
George
 

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