Cylinder...Still Good?

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427cobra
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Real Name: Eric
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Cylinder...Still Good?

Post by 427cobra »

When cleaning the cylinder up I noticed some slight scoring. Was wondering if I can still use the cylinder or do I need to start looking for another one? The engine had good compression on both cylinder before taking it apart (120 psi.)

I am planning on installing new pistons and rings. Like I said just wondering if I can still use this cylinder or what will happen if I do use it? Will the scoring mess up the rings on the new pistons?
Eric A.

"Life is tough, but it's tougher when you're stupid" - John Wayne
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Danzig
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Cylinder...Still Good?

Post by Danzig »

I would use the muriatic acid on this cylinder, this will remove the aluminum deposits. Menards, Home Depot...carry this acid. That looks real good considering what I had found and running in the liquifire. I would get new rings and run it. I also had real good compression prior to my tear down.
1973 JDX8
1978 Liquifire 340
1980 Liquifire 440 CC Racer
1980 Liquifire 440
1982 Liquifire 440


"Gotta Lick It Before You Stick It"
Liquifire 4/6
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Cylinder...Still Good?

Post by Liquifire 4/6 »

It's always difficult to tell by looking at a pic just how bad the damage is. My experience is that pictures usually (not always) exagerate scoring. Yours doesn't look very bad from what I can see and the fact that it was still pumping up 120 PSI suggests that it couldn't be terribly bad. However, from what I can remember, Sportfire mills generally had about 135 PSI when new.....but your rings were likely showing their age. Do what Paul says and I think you'll be good to go.....unless you can really feel distinct ridges when you drag the tip of your fingernail over the damaged area, in which case, I'd suggest looking for a new pot.

Pete
Peter from Roblin, Manitoba
Maj_hazard
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Cylinder...Still Good?

Post by Maj_hazard »

Would a light honing be of any help ???
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guitardude081
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Cylinder...Still Good?

Post by guitardude081 »

With honing you run the risk of stripping the chrome finish out of the bore. It's only about .005 thick. I wouldn't hone it. The biggest thing is to get that cylinder clean. Wipe it down w/ WD-40 until the rag you are using has no dirt or debris on it. Then do what Danzig said and toss in new rings.
~Jack
Owner, Durand Motorsports
1980 Trailfire 340 (Grandpa bought new)
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427cobra
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Cylinder...Still Good?

Post by 427cobra »

Thanks for all the tips. I will give the acid a try. Then hopefully be good to go.

How do you recommend applying the acid? Any certain technique?

-Eric
Eric A.

"Life is tough, but it's tougher when you're stupid" - John Wayne
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Danzig
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Cylinder...Still Good?

Post by Danzig »

I put on some rubber gloves, get a couple towels and poured this stuff on the towel and rubbed away. The acid fumes will smoke. DONT SMELL THIS STUFF!!
1973 JDX8
1978 Liquifire 340
1980 Liquifire 440 CC Racer
1980 Liquifire 440
1982 Liquifire 440


"Gotta Lick It Before You Stick It"
Mr. Deere
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Cylinder...Still Good?

Post by Mr. Deere »

OR YOU WILL END UP LIKE TASKY.


:) BOB
BOB From MASS
OWN: 1 1983 JOHN DEERE LIQUIFIRE 440
1 1973 JOHN DEERE JDX8 440
1 1982 JOHN DEERE SPORTFIRE 440
1 2000 SKIDOO MXZ 600
GOTTA LOVE THAT TWO STROKE SMELL
Rodimus Prime
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Cylinder...Still Good?

Post by Rodimus Prime »

q tip tooth brush all work for miratic acid. Honing wouldnt touch the hard chrome anyways. Looking at it id say its about norm for and engine without airbox or has had a piston replaced once without the bottom end being cleaned up. Check the crank bearings for aluminum deposits or roughness.
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