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Discussion Starter #41
I am not positive on checking the bottom end play, maybe Steve, Roger or NHgravely can help you here.

I do complete engine and transmission tear downs and replace all out of spec parts. If you disassemble the flywheels to inspect the crankpin be ready for the work required to reassemble. I do ball park reassembly of the flywheels ( within 1/16") and then take the assembly to a shop that has been truing Harley cranks for the past 40 years. They bring it in specs and charge very little.

I started checking the rod after rebuild just to see what one in spec looks like. See attached pic......
If you want the xcel work book I created I will try to pm it....
View attachment 2445051
Yes, I would like that on excel. Thanks
 

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Discussion Starter #42
Here is another scenario on this motor. Say the rings are in fact not seating, for whatever reason, causing pressure in the cc and in the transmission. This would explain the delay in smoking after start up until the pressure climbed. This may cause pressure to be blowing splashing oil in the inlet push rod bore into the valve and then to the combustion chamber. This would also explain the oil wet spring area I observed. The smoke before overhaul may have been just bad cylinder condition. We all agree the the chrome top ring takes more break in time and chrome does have it's place. I worked at a major gas pipeline compressor station with V12, fuel injected, twin turbocharged, 4 cycle engines that ran at 330 RPM's that produced 2000 HP. The bore was 15 1/4"x 18" stroke. The oil capacity was about 300 gal. per unit and consumed from 10 to 15 gal. per day. The cylinders were re-chromed with a process that were porous somewhat to retain oil and the rings were cast. There is a place for chrome but maybe not in this gravely if the cast rings are available. Does anyone have a supplier? Thanks
 

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Discussion Starter #45
I will check with Hastings. We also have a few places to check but it might take sometime. Thanks for the input nh.
 

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Discussion Starter #46
Ok, for those of you that were following this post we finally have some good results. We ended up checking the bottom end for anything outstanding and found nothing. All the oil lines and oiling system was checked, we pulled the valves to check for any problem there and found nothing wrong. After replacing, you remember, the first set of chrome rings with another set of chrome it still smoked really bad. We honed the cylinder another .0005 to clean it up and installed a new set of another brand of chrome and that fixed the smoking problem. It seems to me nowadays we have to question quality control more so than 20 years or so ago. There are many aftermarket vendors that to me are in question of there quality. Many of these come from cheap manufacturers as we all know. Thanks for looking and participating with ideas and suggestions.
 

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+1!

Based on what you did, it pretty much has to be a manufacturing flaw in the rings. That's really disappointing. It's been well known how to make piston rings for a century.

I've never tried chrome rings in one of these beasts. Now I'll be sure not to!
 

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Discussion Starter #49
Sometimes R&D is necessary but not cherished when you are trying to do a relatively simple overhaul on a gravely L. If we had these three sets of chrome rings laying beside each other on the bench, and not knowing what we know now, it would have been the ones on the left to go in first!!! Thanks guys.
 
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