Verical hit and miss engine

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hi Brian
the axial dims on the vertical engine crank shaft don't seem to work with the side plate gaskets ?, the the .375 journal doesn't work with the conrod .438 big end hole...which is correct? I have already turned the 3/8 crank journal so I guess i'll use that unless it is critical for some unforseen reason.
Ray M
 
Ray--I will investigate and get back to you later today.---Yes Ray, my bad. I am sending out new drawings of the con rod and cap this evening to everyone who purchased the plans . As far as the axial dimensions on the crankshaft go, it will work with the gaskets with no changes.---Brian.
 
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Ray--The crankshaft endplay ends up being controlled externally by the ignition cam on one side and by the small bevel gear on the other side. My original plan was to have it controlled on the inside by having the two registers on each side of the crank-throws riding against the ball bearings. There are enough accumulated tolerances to make this a very iffy thing. The real story is that the crankshaft is centered by the con rod, which is positioned by the piston, riding in the bore of the cylinder which is bolted to the crankcase. Originally I had made no provision on the crankshaft for the sideplate gaskets. Then when I went to assemble everything and seen exactly how the crankshaft was being centered as explained above, I was glad that I had left that
.030" clearance on each side of the crank throws to the ball bearings. You may find that you have to put a small spacer washer between the small bevel gear and the shoulder on the crankshaft. That is something that you won't know if you need or not until final assembly.
 
I've had all of the fun I can have with this engine. Today it's going up on a shelf with all of it's friends. This is the first engine I have built with cast iron rings, and I must say, they do coast a lot better than previous engines with Viton rings. I will probably use cast iron rings from this point on for any new i.c. engines that I build. I don't really think that I have learned anything new building this engine, but knowledge is cumulative, and every engine does get a bit easier as I go along. I may go back and revisit some of my existing engines, but right now I'm a bit burned out on machining in general. One of the people who purchased a plan set from me asked if it would be reasonable to remove the inner grease seal from the crankshaft bearings and wash out the grease, as the engine has an oil sump and the bearings would get lubricated that way. I think that would be a good thing to do in terms of how long the engine would coast, but I don't know if the one remaining outer grease seal on each bearing would be sufficient to prevent crankcase oil from leaking out. this is something that would be good to know if it made an improvement to the engines coast time, and whether or not it made the engine leak crankcase oil around the bearings. Thanks again to the many people who followed this build.---Brian
 
I've had all of the fun I can have with this engine. Today it's going up on a shelf with all of it's friends. This is the first engine I have built with cast iron rings, and I must say, they do coast a lot better than previous engines with Viton rings. I will probably use cast iron rings from this point on for any new i.c. engines that I build. I don't really think that I have learned anything new building this engine, but knowledge is cumulative, and every engine does get a bit easier as I go along. I may go back and revisit some of my existing engines, but right now I'm a bit burned out on machining in general. One of the people who purchased a plan set from me asked if it would be reasonable to remove the inner grease seal from the crankshaft bearings and wash out the grease, as the engine has an oil sump and the bearings would get lubricated that way. I think that would be a good thing to do in terms of how long the engine would coast, but I don't know if the one remaining outer grease seal on each bearing would be sufficient to prevent crankcase oil from leaking out. this is something that would be good to know if it made an improvement to the engines coast time, and whether or not it made the engine leak crankcase oil around the bearings. Thanks again to the many people who followed this build.---Brian
That is what I have done also. I have over 20 engines which I have built and I really do not need any more. I have been going through the existing engines and getting them to run better and in some cases look better. I have learned a lot since I made my first engine in 2006. Things that were difficult back then are much easier now due to better knowledge and better machines and better tooling. I frequently end up finishing an engine and getting to run OK and moving on. At this point I am better able to figure out why it runs for three minutes and then quits for instance. Also I have used o rings on some of the engines and I am replacing them with CI rings. Still interesting and beats TV any day.
 
That is what I have done also. I have over 20 engines which I have built and I really do not need any more. I have been going through the existing engines and getting them to run better and in some cases look better. I have learned a lot since I made my first engine in 2006. Things that were difficult back then are much easier now due to better knowledge and better machines and better tooling. I frequently end up finishing an engine and getting to run OK and moving on. At this point I am better able to figure out why it runs for three minutes and then quits for instance. Also I have used o rings on some of the engines and I am replacing them with CI rings. Still interesting and beats TV any day.
 
Gordon, If I wrote about where I stand regarding my engine building it would be very, very close to your post.
My first IC was ~2006...have built aprox 20 engines...I spend some time periodically running and cleaning them up. I make all the rings out of cast iron. The one exception is the "henry ford fiirst engine" which is viton 'o' rings. Ironically one of my first engines (2003) was Bob Shores "Silver Angel", I am currently building Brian Rupinow's larger version.
I find myself taking more time adding finishing touches/changes to each part...
Like you say beats TV anytime, especially for an old man...83.
Ray M
 
Ray--The top of the crankcase body is configured to hold an o-ring to provide the seal between the crankcase and the cylinder. As luck would have it, the day I assembled everything I didn't have an o-ring the right size, so I used an 0.030" gasket instead. It will work either way, with a gasket or with an o-ring.---Brian
 
I forgot to dimension the depth of the piston ring groove.---Here is the drawing
---Brian
IDftpy.jpg
 
I used to have an issue getting hold of o rings, not many places stock them because of their shelf life. I'm not sure if you have the same issue in Canada, but I've found this online shop that stock them and offer express delivery which might help you: https://www.accu.co.uk/en/1619-o-rings
 
I used to have an issue getting hold of o rings, not many places stock them because of their shelf life. I'm not sure if you have the same issue in Canada, but I've found this online shop that stock them and offer express delivery which might help you: https://www.accu.co.uk/en/1619-o-rings

Years ago I bought an assortment of buna-n o-ring material in different lengths and diameters. It is a fairly simple process to make o-rings to size using 'super glue'. They work well for small model belting and even static seals in a pinch...
I haven't had a noticeable problem with shelf life, does the durometer change?
Ray M
 

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