Another Internal Combustion Engine

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Cut out two tank stands and polished them up.
IMG_4197.JPG

Fuel tank installed.
IMG_4202.JPG

A couple weeks back I mentioned that I wasn't completely happy with the exhaust valve. I spent a couple of hours at that time working on the exhaust valve and seat and I thought I had it sealing.
Well it wasn't and after another couple of hours messing with it I decided I should just pitch it and start over.
So a slight delay while I make a new valve and guide.

Thanks for looking
Ray
 
Yes you are right K2 but after dropping almost all of them on the floor at one time or another and then trying to find them can be frustrating.

The outside of a piece of round aluminum stock is skimmed to get a consistent OD.
The inside is then drilled out to remove the waste.
This shows cutting the lip for the end pieces of plexiglass to fit into.

View attachment 161898

Cutting the end pieces to size using pressure from the tool post only to hold them in place.

View attachment 161899

All the gas tank parts before assembly.
View attachment 161900

Thanks for looking
Ray
I like the looks of the aluminum tank Ray!

John W
 
Thanks Terry and John

First up some pictures.
IMG_4204.JPG

IMG_4205.JPG

IMG_4207.JPG

IMG_4209.JPG


And the video


I am not entirely happy with the engine as it is and will continue to work on some problems.
Future plans
Get rid of the bevel gears. They are too noisy. I have some helical gears on order.
Maybe lower the compression to calm the jumping and allow for a longer miss period.

Thanks for looking
Ray
 
Thanks Terry and John

First up some pictures.
View attachment 161968

View attachment 161969

View attachment 161970

View attachment 161971


And the video


I am not entirely happy with the engine as it is and will continue to work on some problems.
Future plans
Get rid of the bevel gears. They are too noisy. I have some helical gears on order.
Maybe lower the compression to calm the jumping and allow for a longer miss period.

Thanks for looking
Ray

Looks like a nice runner.

I do have a question though, why is the rod offset in the piston? I had seen it in some earlier posts and thought it was an illusion, but I don’t think it is (but maybe)
 
Very nice running. The hit miss cycle is very pronounced.
 
Thanks Terry and John

First up some pictures.
View attachment 161968

View attachment 161969

View attachment 161970

View attachment 161971


And the video


I am not entirely happy with the engine as it is and will continue to work on some problems.
Future plans
Get rid of the bevel gears. They are too noisy. I have some helical gears on order.
Maybe lower the compression to calm the jumping and allow for a longer miss period.

Thanks for looking
Ray

Run well, Congratulations !
Thanks for sharing . 👍👍👍
 
Thanks Terry and John

First up some pictures.
View attachment 161968

View attachment 161969

View attachment 161970

View attachment 161971


And the video


I am not entirely happy with the engine as it is and will continue to work on some problems.
Future plans
Get rid of the bevel gears. They are too noisy. I have some helical gears on order.
Maybe lower the compression to calm the jumping and allow for a longer miss period.

Thanks for looking
Ray

Why not see if you can get some spiral bevel gears? I think I saw small ones for sale on AliExpress. Fewer changes needed than going to crossed helical!
 
Nice Job. Great to see it running.
Thanks Tony

Why not see if you can get some spiral bevel gears?

The problem for this build is there is not enough room on the crankshaft for straight or spiral bevel gears. If I had made the crankshaft longer in the beginning I wouldn't have had this problem.
The drive gear fits on a 12mm shaft so in order to have enough meat for the set screw it is rather large. That makes the driven gear twice as large and there wasn't enough room on the crankshaft for the gears and the flywheel. That's why I cut both gears down in size as much as possible and I assume that has caused my noise problem. I tried to file the ends of the teeth but since they are fairly hard I made little progress.
Hopefully the helical will run quieter and they will definitely take up less space. The side shaft will be relocated lower under the drive gear and the supports can be flipped over and new holes drilled and taped. The arm that rides on the cam will be relocated lower and may need to be modified. The turn buckle can be lengthened to attach to the upper arm so no change here.
It remains to be seen just how everything will turn out.

Thanks
Ray
 
I do have a question though, why is the rod offset in the piston? I had seen it in some earlier posts and thought it was an illusion, but I don’t think it is (but maybe)
Oxford asked this question earlier and I replied that I had made a measuring error when boring the cylinder liner hole.
In a private message we discussed that the offset I had made in the piston to correct the measuring error looked wrong. I went out to the shop and sure enough I had the connecting rod turned 180 degrees from where it should have been. There must have been enough play in the connecting rod bearings as not to cause a problem.
Turned the rod over.

Thanks again
Ray
 
Thanks Terry and John

First up some pictures.
View attachment 161968

View attachment 161969

View attachment 161970

View attachment 161971


And the video


I am not entirely happy with the engine as it is and will continue to work on some problems.
Future plans
Get rid of the bevel gears. They are too noisy. I have some helical gears on order.
Maybe lower the compression to calm the jumping and allow for a longer miss period.

Thanks for looking
Ray

Wow Ray, another really great engine! That side shaft flyball governor is amazing. Congratulations on a fantastic runner.

John W
 
Last edited:
Pages back in this thread Vietti asked this question.

I will be interested in your experience with the quad rings. I have tried both styles without seeing any difference. I have talked to some who like them and some that don't.

I have noticed almost no amount of blow by and mess out the back of the piston. Is it because of the square rings or the steel liner. The compression is very good and the friction is actually very low compared to a round o-ring or I may have just got lucky on this engine.

Ray
 
I have made some changes to the engine over the past couple of days. I originally wanted a 5 to 1 compression ratio for the engine but after I checked the completed piston deck height I had 6 to 1.
The easiest solution was to add a plate under the head and have two gaskets.
IMG_4216.JPG

This is the stack up.
IMG_4221.JPG

I did help with the bucking and jumping and didn't affect the engine running.

The helical gears should be here soon.

Thanks for looking
Ray
 
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