new side valve engine fom home made castings

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that is pretty - I have a drawing somewhere where the fuel intake is worked into the intake valve seat..
 
A little more progress on this engine to share
I drilled tapped and counterbored the spark plug holes, fixed the valve seats into the head with loctite then drilled the passageways into the valves
The carb has been mounted and an exhaust was fabricated fron stainless steel and mounted to the cylinder

I think its getting close to the end now
Regards
Dougie

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I am at the stage with this engine where I am ready to put it together and see if everything went round and round without any bits bumping into each other that wern't meant to.

Before I could do that I had to set the cam timing, here are some pictures of the method I used.

First pic shows the timing gears with alignment marks, the engine was set to TDC and the crank gear and the two idlers were punch marked.

To set the cams in the correct position I made a small plate to join the two tappets together, thats the second pic.When this plate is pushed down onto the flank of each cam it sets the camshaft in the correct TDC position with the exhaust closing and the intake opening.
With the cams secured the portion of the shaft where the cam gear will sit was coated with loctite and the cam gear slid into place.

Once the loctite set I could fit the valves and check that everything rotated freely, it did!!

The next pics show the fuel tank. the main body was bent around a hardwood former, the filler cap, outlet and the ends were silver soldered together. The sides were shaped on the sander and the cross formed into them, these were given a coat of tipex round the edges, fluxed on top of that and the ends soft soldered into position
Once it cooled the flux was removed with warm water and the tipex with cellulose thinners.

As allways, comments or suggestions greatly appreciated

Dougie

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its all looking really nice. what type of tool did you use to form the "X" in the side of the gas tank? id like to see more about that if you have any pictures?

really sharp work!
 
I discovered I still had one or two small add ons to make before I can put it together

Tonight I made the combined oil filler/crankase breather
The first pics are the three basic components, the cup valve, stainless ball and the retaining cover. The next are the valve assembled and then fitted to the street elbow which will be fixed to the cam cover plate

The cover plate was originally aluminium but tonight I changed it to brass and etched my name and date into it, I will post some pictures tomorrow

Werowance, the cross was formed by cutting grooves in the form of the cross into a block of aluminium with a 3/16 ball nosed end mill, this was marked with the outline of the end plates. The plates were then laid on the ally and a piece of 3/32 silver steel, cut to the size of the cross, laid above the grooves and hit with a hammer to set the copper into the groove. A little on one then the other till the steel will sit on its own without moving then given a good whack to finish
This method also slightly domed the end plates, it was unintentional but turned out ok
I will post a pic of the former tomorrow

Regards

Dougie

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This is the cover for the cams, I etched it with ferric chloride for about three hours. Once the etched area has been painted the lettering will stand out a bit more. The last pic shows the crankcase vent fitted to the plate

Dougie

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These next pictures are in resonse to the question from werowance about forming the cross on the fuel tank end plates

The first pic is the block of aluminium with the cross cut into it, next is a scrap of copper laid on the block with the forming pin laid on top over the cutout in the ally. A couple of taps starts to push the copper into the form, first one side then the next. The second last pic shows the cross starting to form on the outside.

Once the pin will sit on the copper without rolling off a couple of good whacks finish the job, the last pic shows the finished plate.
All this took less than five minutes

Regards
Dougie

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Hi Dougie
The more I look at the fuel tank the more I like it. To me the copper gives it sort of a warm agricultural feel like something off an antique tractor or utility engine. Your etched cam cover has me wanting to remake a couple of steam chest covers. scratch.gif
 
Well, a couple of nights in the shed bending 1/16th copper oil pipe, making some pipe unions and assembling the first of the pair of engines with only one strip down to fit a bit I forgot and here we are.

This is the first full assembly and it is now ready to test

The crankcase has 35ml of oil, that brings it up to just kiss the crank balance weight. The part I forgot was the con rod dipper to splash the oil about, I had to take the engine apart and solder the dipper to the big end, that is no easy task. It is quite a complicated procedure to fit the crank through the main bearing hole, line up the bigend and slip it onto the crankpin. Then fit the balance weight and gear driver web through the access hole, all bloody fiddly and designed to test my patience!!

All I have to do now is solder together the leads for the hall sensor and make the ignition circuit to the design on this forum by J Geddes

I hope you enjoy

All comments and suggestions greatly appreciated

Dougie

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Here are some pictures of the ignition setup I plan to use

The first is the coil attached to the ignition circuit which is fixed to the top of the box, next is the box with everything inside.
I set everything up with the engine clamped to the bench to test. I would like to say it ran after a couple of flicks but it didnt. A leaky head gasket and flooding were the main problems, I changed the gasket to silicon sealant and let it set overnight

Testing the following day, progress was in the form of a few short runs then loss of compression through the exhaust valve, this meant stripping the head and splitting the gasket. The culprit was a bit of cured silicon that stuck on the valve seat

This meant a rethink so all the silicon was removed and a thicker gasket was cut from gasket paper and and the engine re assembled, can you see a pattern evolving?

This was a definite improvement, a lot of fiddling with fuel needle, fuel seat settings and we have liftoff. I found the engine wont run with the air shutter more than a quarter open but it runs all the same

If I have done this right there should be a link to the engine running on youtube
Hope you enjoy

Dougie
[ame]https://www.youtube.com/watch?v=kf1wD8aCzjU[/ame]

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Dougie
Compression and valves must be the bane of a model engineer’s existence.
Well done and congratulations on a runner. It’s great to see all the work you’ve none come together.Thm:
 
I have been messing around with the carb settings on the engine and have got it to run with the air shutter fully open, this gives a degree of speed control but it has a bit of a delay. The best speed control is by using the spark advance or retard.
I lashed up a cooling system from an old mapp gas can which works well but I think the water tank could do with being a bit bigger
The oil pump I designed into this engine has proved to be very effetive, too effective as when it runs oil is pumped out of the main bearing, I now plan to either block off the feed to the main bearing and have it feed only the gearbox or just leave it as a manual pump
The engine was burning a lot of oil at first which seems to have settled and the oil level inside the crankcase has dropped, I think I had too much in there to begin with. All the parts designed to be lubricated by splash seem to be being so, a fair bit of oil comes out of the inlet tappet bush but not the exhaust so when I come to strip this for paint I will make a new bush
Hopefully this link will show the engine running with the cooling sytem and is I hope a bit clearer than the last one

Thanks for all the kind comments

regards

Dougie
[ame]https://www.youtube.com/watch?v=cb23_W5kzWY[/ame]
 
You were right Charles
After an unsuccessfull search for a maroon colour I settled on mid brunswick green
I can use this colour on some of my full size Listers
Dougie
 
Re-visited the thread and read through the whole process. From front to back....and excellent tutorial, and interesting fabrication of this classic engine design. Congrats!

Can't wait to see the engine wearing some lipstick.


Frank
 
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