These should be the exhaust lifter functioning, and the engine running
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Thanks Cogsy.
I found the magic!
And yes, the ring wear might have been from trying to break them in with the lathe spinning the motor, but I'm not sure they were ever going to work. Strange, because that method has worked for me before. (torch heating, not running in that way)
I found the magic!
And yes, the ring wear might have been from trying to break them in with the lathe spinning the motor, but I'm not sure they were ever going to work. Strange, because that method has worked for me before. (torch heating, not running in that way)
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Cogsy
Well-Known Member
I've only ever done the torch heating also - it was the first way I tried and it's always worked out well (so far...).
Thanks Ted, Minh Thanh,
That is a very different cam shape. There is a 1/2" wheel that rides on the came and , I think, helps to smooth out the motion. It does drop off suddenly, but the indexer needs an abrupt motion to turn it. So the cam drops off, the spring pulls the lifter down, the indexer catches on the flat spring on the right side, and turns 90 degrees. Straight wire spring on the left stops it at 90
Some pictures, although the cam is behind the flywheel and governor, and a little hard to get a clear look
the roller just as it comes on top of the cam,
as it is about to drop off the cam
A bit dark, but the same position from the other side
Maybe this one is better
with the cam lobe and lifter all the way down, almost no contact with the cam.
The instructions say to turn the cam so the exhaust valve is closed 3 degrees after Top Dead Center (TDC) .
I hope that explains well enough, it is an interesting mechanism, and I think it is smoother than the cam would make you think.
I had a slow motion video, but when I transferred it, it came out as a still.
Thanks for looking,
Doug
That is a very different cam shape. There is a 1/2" wheel that rides on the came and , I think, helps to smooth out the motion. It does drop off suddenly, but the indexer needs an abrupt motion to turn it. So the cam drops off, the spring pulls the lifter down, the indexer catches on the flat spring on the right side, and turns 90 degrees. Straight wire spring on the left stops it at 90
Some pictures, although the cam is behind the flywheel and governor, and a little hard to get a clear look
the roller just as it comes on top of the cam,
as it is about to drop off the cam
A bit dark, but the same position from the other side
Maybe this one is better
with the cam lobe and lifter all the way down, almost no contact with the cam.The instructions say to turn the cam so the exhaust valve is closed 3 degrees after Top Dead Center (TDC) .
I hope that explains well enough, it is an interesting mechanism, and I think it is smoother than the cam would make you think.
I had a slow motion video, but when I transferred it, it came out as a still.
Thanks for looking,
Doug
When I saw Hepworth and Grandage piston ring manufacture, they took the near-fished rings and "barrelled" them by running in a cylinder (the size and material of the engine's cylinder) - just with oil - NOT carborundum! - using a machine that rotated the cylinder slowly while oscillating the rings in and out with a slight eccentricity of motion so the edges of the rings were slightly pre-worn - thus when the car engine was built almost no running-in was required. - NO back pressure from combustion there - just the reciprocation motion to simulate an engine. I think they had 1/2 to 1 hour of that treatment - but can't be sure.... (notes were archived at work about 20 years ago). They had a lot of machines, as the rings were built onto packs of 20 or 30 and run - and a bloke managed many cylinders - loading and unloading the rings onto the mandrel and fitting into the bores and linking to the driving rod - then engaging a clutch to continue the lapping.
May be of interest?
K
May be of interest?
K
Steamchick,
Were the rings split at that point, or still complete rings? It seems like a good idea (must have worked), though I'm not sure how I'd accomplish it in my shop. I think the idea of running in an engine on the lathe would be similar, but the rings are in their grooves so can't float as much.
It's worth some thought...
Thanks
Doug
Were the rings split at that point, or still complete rings? It seems like a good idea (must have worked), though I'm not sure how I'd accomplish it in my shop. I think the idea of running in an engine on the lathe would be similar, but the rings are in their grooves so can't float as much.
It's worth some thought...
Thanks
Doug
Minh Thanh,
It is four cycle. The exhaust valve lifter goes up and down every revolution of the crankshaft, but the indexer on top rotates 90 degrees to a shorter side and doesn't contact the exhaust valve every other turn. I got a video slowed down enough so I think it will explain itself.
I hope this clarifies . there is a lot of motion going on
Thanks for looking,
Doug
I found another good one. Use the little gear (settings) in the lower right to slow it down more.
It is four cycle. The exhaust valve lifter goes up and down every revolution of the crankshaft, but the indexer on top rotates 90 degrees to a shorter side and doesn't contact the exhaust valve every other turn. I got a video slowed down enough so I think it will explain itself.
I hope this clarifies . there is a lot of motion going on
Thanks for looking,
Doug
I found another good one. Use the little gear (settings) in the lower right to slow it down more.
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