top overhaul cost on an O-300D

These engines get rebuilt after every 3.6 seconds.

top-fuel-dragster-engine-rebuild.jpg


https://www.motor1.com/news/265961/watch-dragster-engine-get-rebuilt/
 
Tom-D said:
Where do the you draw the line?-- 60/80 --
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I don't replace a cylinder simply due to compression test numbers. Will look at any other issues as well to include using OEM guidance when needed. Have seen engines flying just fine (and legally) with some compression numbers in the 50s/80. So it depends.
 
Tom-D said:
there was a time the military would change the whole engine at 400 hours
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Heck, Tom, in late 1944 and about a quarter of 1945, the 21st Air Force in the Marianas was lucky to get 50 hours out of the 3350s on B-29s. That couldn't have been very comforting to the crews flying 3,000 mile missions over the Pacific.
 
@DKirkpatrick

call Seth Record @ P.A.P.

https://www.pap2fly.com/

you can thank me later.

(he can even cryo the cylinders...)

Seth is the kind of guy who, when you order six cylinders, doesn't order six from the factory. He orders 10. Then he weighs everything and takes the six closest matched and puts them on one pile...the four oddballs go on another pile and are sent back.

then he reworks the valve seats and guides because he doesn't like the factory's sloppy job.

Mr. Anal Retentive... A very good trait when it's somebody you're dealing with on aircraft engines!!

He also overhauls cylinders if that's the way you decide to go.
 
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Tom-D said:
Where do the you draw the line?
-- 60/80 --
Click to expand...

I draw the line wherever the master orifice says it should be--combined with the manufacturer's recommended guidance.

I've had cylinders that barely met the limits one year, and then passed with flying colors when rechecked a month later...

A borescope look of the internals and a good picture of the burn patterns on the exhaust valve head are more useful at determining overall health than the actual leakage test.

It's a bit of art & science, but It's definitely not rocket science :)
 
Tom-D said:
things to worry about when working on cylinders
do the logs say they were already over sized ? .015" is the limit
who has the tools to do cylinders? the machine that does that job is $50,000. used.
cylinders must have a bushing replace in the rocker are box, price that bushing, plus the hone that sizes it.
Tommy has done a lot of cylinder, the 0-300 price is $969.00 I found I can't compete. You want a custom cylinder plan on $1200.

than they crack.
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Bremerton Wa. use to have a cylinder grinding machine to turn oval shape cylinders back to round, not sure they do that anymore. How many cylinder repair stations have that kind of machine, not many so you get back a oval cylinder as a repaired. You get what you pay for cheap repair of a cylinder or new Tom is right, just how lucky do you feel.
 
3393RP said:
Heck, Tom, in late 1944 and about a quarter of 1945, the 21st Air Force in the Marianas was lucky to get 50 hours out of the 3350s on B-29s. That couldn't have been very comforting to the crews flying 3,000 mile missions over the Pacific.
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At least they had four of them! -Skip
 
brien23 said:
Bremerton Wa. use to have a cylinder grinding machine to turn oval shape cylinders back to round, not sure they do that anymore. How many cylinder repair stations have that kind of machine, not many so you get back a oval cylinder as a repaired. You get what you pay for cheap repair of a cylinder or new Tom is right, just how lucky do you feel.
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The last time I saw that machine it was being scrapped, because no one knew how to use it.
 
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