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Discussion Starter #1 (Edited)
So the cylinders are off (real PITA) but I can't get a solid answer on whether to hone the cylinders and replace the rings, or just put everything back the way I found it based on the argument that the currents rings are matched to the cylinder?

Several shops have said always home and replace at this point, but an equal number have said not to do so without reason.

My thinking is that there is no way I'll ever get the rings back in the same spot (even though I took pics of how they came out). Hell, they probably moved when I was taking them out before I even had a chance to take the pics.




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Discussion Starter #3
Thanks for pointing that out Corsair - damn spell check (and my fat thumbs).

The cylinders are not damaged, and the rings are installed staggered (roughly 12, 3, and 9 o'clock positions).

I made the mistake of asking my father-in-law (who said 'no' when I asked to marry his daughter nearly 30 years ago). He is a retired TWA mechanic (actually worked on Stratoliners for TWA, but I digress). He said only an idiot would pull the pistons out of the cylinders and not replace the rings because no matter what I did I would not get the rings back in the same position during reassembly and the result would be oil consumption requiring me to pull the cylinders again, hone them, and replace the rings - so why not just do it now (unless I'm the idiot mentioned).

However, I think he is focusing too much on what should be done with a HUGE aircraft engine with the risk of failure being catasrophic. So Corsair, what say you to that???

At this point, I really don't care either way. There is nearly no additional work (just pulling the rings off and putting new on). I already have an order coming from Patrick Racing so I would only need to add the two ring sets (OK that might cost a bit more, but relatively speaking, not much). I don't own a honing wheel, but I could have the machine shop do it for $5 per cylinder.

So my only question is what is best overall for the engine long-term? Because I damn sure don't plan to open this thing again!
 

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Miescha, after reading your response I would go ahead and have the cylinders honed and change the rings. Like you say, it's a PITA to pull them but since you're already there, go for it.

I've changed cylinder heads on large Merlin engines without changing the rings and they kept the same oil consumption. In my neck of the woods, getting cylinders honed would cost you a bill at least. But at 5 bucks, what a deal. Just make sure to stagger your new ring 120 deg apart. this allows for better sealing.
 

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youre already in there. Rings are (should be) relatively cheap, Id replace them. Honing....meh is there damage? If we are honing and all that Id be adding some higher compression pistons too (since we are already robbing the piggy bank, whats another few missing coins?)
 

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Discussion Starter #6
Rings are cheap, about $50 for both sets.

Don't know where I would find higher compression pistons.

For every 'expert' opinion I find saying you should always replace rings and hone, I find another 'expert' that says keep rings and never hone (these are all based on no known problems).


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Discussion Starter #8
So I need to add that new research indicates this engine is the recipient of a Patrick Racing Big Bore Kit, head port & polish, exhaust manifold port & polish, and crankshaft lighten & balance (whatever the hell that is).

Gaskets will need to come from PR, and rings also if I go that route. PR says cylinder is Nikasil coated and cannot be bored or re-coated again, but can be honed.

I'll check cylinder specs and ring gap today before getting PR opinion on honing, but they didn't seem like it was a "must do" at this point.

They also said it is not sleeved - I don't know how it came from Yamaha.


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That ain't just any Strat, that's my Strat.

Afraid? Not at all. I'm only afraid of a certain blue chevy pick-up with a bent front bumper. :D
I guess I shouldnt tell you how it REALLY got bent then (takin apart the blue bike club.. one at a time!!) :p

Actually, Im sellin that bad boy this year, or trading it for something sweet!
 
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