V-TWIN--MAYBE V4

[Brian Rupnow]

I do flame harden and oil quench the cams and the lifters. That's why I make them from 01, so I can harden them.---I just did that to the cams I made earlier today.---Brian

[Brian Rupnow]

Machining and fabrication is complete. This video shows operation of the cams, push-rods, and rocker arms. Next step will be to see if I can persuade this engine to run.
<a href="https://www.youtube.com/watch?v=GHKm-rOTpUE" target="_blank">http://www.youtube.com/watch?v=GHKm-rOTpUE</a>

[Art K]

Brian,
I did see that you asked for help with the cam tables, but wasn't sure I could help. I have used the cam calc program to make my cams and I don't think its compatible with windows 11. I did set up a cnc program the last time I made a cam that worked quite well. I do have a new desktop and ordered it with 10 as I can always update it but can't go back to 10. Your work looks good nice radiused flanks and nose on the cams!
Art

[Brian Rupnow]

Today I assembled the cams for the other cylinder and made up a pair of pushrods. The rockers now operate on both sides when I turn the engine over. I went across town to Hercules O-ring and begged a couple of 1" i.d. Viton o-rings to use for my head gaskets. This is getting harder and harder to do---I used to know all of the Management there, and they gladly gave me whatever Viton rings I needed in exchange for $5 for their coffee fund. The management is all new there now, and they don't know me.  I find it difficult to order Viton o-rings in the sizes I need unless I want to buy a thousand of them. I leak tested my gas tank by filling it full of Naptha gas and setting the engine on a piece of white paper overnight. The paper had no tell tale stains on it in the morning, and the fuel level stayed the same in the tank overnight. I have to make up gaskets for the bottom of the cylinders where they attach to the crankcase.---There is no compression there, but the engine has an oil base and splash lubrication, and if I don't put gaskets there it will leak oil.

[Brian Rupnow]

Today was the day to start thinking about piston rings. I have a number of heat treated rings which were originally made when I built my 7/8" bore horizontal i.c. engine. Whenever I set up to make piston rings, I make a bunch of extras, and they do get used up. These pistons are prototypes. They are made of cast iron, and the top two ring grooves get the heat treated cast iron rings. The third groove down from the top of the piston get a single Viton o-ring. (Which you can see on the left side of the picture). Theory here is that the Viton rings will give immediate good compression to start the engine. After the engine has started on it's own and ran for an hour, the cast iron rings will "wear in" to the cylinder to provide compression. The rings in the picture haven't been ground for flatness nor "fit" to the pistons, that will be done tomorrow.

[crueby]

After the run-in time, do you take away the viton ring?

[Brian Rupnow]

Chris---there's no real reason to take it away. I have heard (but never experienced) that when  one of these small engines runs for a full day at a show, the Viton rings wear out rather quickly. Non of my engines run for a full day. I have never had a Viton ring wear out. I have, however, experienced the heartache of trying to get a new engine with cast iron rings to start. I have all the equipment to make good, heat treated cast iron rings. That being said, I have experienced utter misery trying to get enough compression to get the engines running. Once they do start, the rings 'bed in' fairly quickly and the compression comes up.  These pistons are a "Try it and see what happens" kind of thing.----Brian

[Brian Rupnow]

Today the cast iron rings were finished "to size" and installed on the pistons. The Viton ring was added to the pistons as well. Using a tapered ring compressor, the pistons were installed into the cylinders. Ended up being a very tight fit, but they are in, the cylinder walls didn't get scored in the process, and I'm happy with the fit. In this picture, the pistons have been shoved thru the cylinders until the piston pin hole is just visible, enough to get the piston pins started into place. The rings are all still compressed in the cylinders. One of the things about a small bore engine using knife and fork connecting rods is that the connecting rods  (at least the forked one) won't fit thru the hole in the cylinder. This means that the piston pin must be installed thru the piston and rod while the rods are still attached to the crankshaft.

[Brian Rupnow]

The pistons with rings are installed in the engine. It is very, very stiff. It is too stiff to consider running on it's own. I used a cheater bar to turn the crankshaft thru 360 degrees, and when I was sure there were no definite "Hardstops" in the engine, I turned it over 200 times by hand. This freed things up to the point where the engine would turn over, but still stiffer than Hell. I filled the crankcase with oil, gave a shot of oil down each cylinder (the heads are not on the cylinders). I put my 8" v-belt pulley on the crankshaft and my two inch v-belt pulley on the electric motor I have, connected them up with a v-belt, and set it up to run for a half hour out in my main garage. I don't have any work planned for the rest of the day, as I'm off to see my friendly neighborhood dentist this afternoon.

[Brian Rupnow]

So--we are almost ready to rock and roll!!! Head gaskets are in, rings are in, everything that bolts together is bolted together (except the gear guard) which will be installed after the engine has been ran. I have to set the valve and ignition timing before I attempt to start the engine, and do a bit of electronic rigging for the ignition. Wish me luck peoples.-----Brian

[crueby]

Best of luck!   

[Admiral_dk]

Wish you luck and joy on the last bit here 

Per

[RReid]

Good luck, Brian.
I think the IC world is run by demons that feed on frustration. They seem to demand a certain tribute before allowing a first start. Hopefully they will be easily satisfied!

[Brian Rupnow]

Rreid--Frustration devils---I like that. I've built about 40 engines now. They all run, but many times I have wished I could have George Britnel and Sid both sitting here in my office to tell me what the heck I'm doing wrong.

[Brian Rupnow]

So, what did I do today on the engine?---Not much that shows, really. I cobbled together a wooden base that would hold one of my cylinders truly vertical. Setting up the valve timing is a lot easier if I start with a cylinder that is truly vertical, rather than laid over twenty five degrees.  Of course, before you can set the valve timing, you have to set the correct valve lash. This took me down the road of having to finalize my valve lash adjusting screws and soldering the knurled tops onto the #5 bolts---and putting c-washers on the rocker shafts and on the shafts for the hardened donut that fits on the end of the rocker arms.---In the middle of all that a man with an idea for a new invention showed up at my place and we discussed that for two hours.---Then I had to mow the lawn, whipper snip the weeds, and blow all the cut grass off my Unistone driveway so it wouldn't start sprouting grass all over the driveway. Then I got an email from someone I had sold a set of drawings to for my 7/8" bore horizontal engine, saying that a bunch of drawings were missing from the package I sent him. I went thru all the files on that engine and he was right, I had to chase down about 20 drawings, save them as pdf files and send them to him. It was an interesting day!!!