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  #1  
Unread 09-07-2006, 10:25 PM
kamikaze kamikaze is offline
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Default SKOOLS - rebuild advice needed

Skools:

I am thinking about rebuilding my 235 this winter (compression across each cylinder is currently 75 PSI. Compression was 95 PSI at start of the season).

I recently replaced the head gaskets and verfiied that none of the cylinder walls are scored, so my question is: Can I just hone each cylinder and replace the rings, Or do I need to bore and replace with over sized pistons. What would you recommend is the BEST way to go???

Thanks

Kamikaze
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  #2  
Unread 09-07-2006, 10:25 PM
kamikaze kamikaze is offline
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Default SKOOLS - rebuild advice needed

Skools:

I am thinking about rebuilding my 235 this winter (compression across each cylinder is currently 75 PSI. Compression was 95 PSI at start of the season).

I recently replaced the head gaskets and verfiied that none of the cylinder walls are scored, so my question is: Can I just hone each cylinder and replace the rings, Or do I need to bore and replace with over sized pistons. What would you recommend is the BEST way to go???

Thanks

Kamikaze
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74 V20 CC with a 150 Johnson (Gone but not forgotten)
89 V20 Cutty with a Tower (Build in process)
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  #3  
Unread 09-08-2006, 01:02 AM
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Default Re: SKOOLS - rebuild advice needed

if no scoring you can hone and re-ring or just buy new pistons kits for all cylinders that have new piston, pin, c clips, and rings for around 40 a piece. either email [email protected] or call them at 847-526-6211 after 11 am.
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  #4  
Unread 09-08-2006, 01:02 AM
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Default Re: SKOOLS - rebuild advice needed

if no scoring you can hone and re-ring or just buy new pistons kits for all cylinders that have new piston, pin, c clips, and rings for around 40 a piece. either email [email protected] or call them at 847-526-6211 after 11 am.
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  #5  
Unread 09-10-2006, 06:37 PM
76GMC1500 76GMC1500 is offline
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Default Re: SKOOLS - rebuild advice needed

There is more to cylinder wear than scoring. *You need to measure the cylinder for taper. *Take measurements at the top middle and bottom of the cylinder. *All engines wear differently, most wear more at the top, a small block Chevy wears most in the center. *Wherever it is widest, if it's out of spec, it will cause premature wear of the piston ring grooves. *As the piston travels down in the cylinder, the ring expands and contracts to conform to varying bore diameters. *Excessive ring groove wear will lead to broken ring lands and piston rings.

If there is no ridge at the top of the cylinder caused by the ring wearing into the cylinder walls, you are generally safe to just hone. I still suggest you have the cylinders measured for taper anyways. Your engine will run quieter and last longer if you build it right.
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Unread 09-10-2006, 06:37 PM
76GMC1500 76GMC1500 is offline
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Default Re: SKOOLS - rebuild advice needed

There is more to cylinder wear than scoring. *You need to measure the cylinder for taper. *Take measurements at the top middle and bottom of the cylinder. *All engines wear differently, most wear more at the top, a small block Chevy wears most in the center. *Wherever it is widest, if it's out of spec, it will cause premature wear of the piston ring grooves. *As the piston travels down in the cylinder, the ring expands and contracts to conform to varying bore diameters. *Excessive ring groove wear will lead to broken ring lands and piston rings.

If there is no ridge at the top of the cylinder caused by the ring wearing into the cylinder walls, you are generally safe to just hone. I still suggest you have the cylinders measured for taper anyways. Your engine will run quieter and last longer if you build it right.
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  #7  
Unread 09-10-2006, 07:22 PM
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Default Re: SKOOLS - rebuild advice needed

Quote:
Originally Posted by kamikaze
Skools:

I am thinking about rebuilding my 235 this winter (compression across each cylinder is currently 75 PSI. Compression was 95 PSI at start of the season).
Isn't that odd that all six were 95 and now all six are 75??...
??? ...
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'95 V-21/ BF 150
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  #8  
Unread 09-10-2006, 07:22 PM
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Default Re: SKOOLS - rebuild advice needed

Quote:
Originally Posted by kamikaze
Skools:

I am thinking about rebuilding my 235 this winter (compression across each cylinder is currently 75 PSI. Compression was 95 PSI at start of the season).
Isn't that odd that all six were 95 and now all six are 75??...
??? ...
__________________
'74 V-20/ BF 150
'95 V-21/ BF 150
'84 V-20/ 200 2.4 Merc
'87 V-20/'18 F150 Yamaha



http://www.wellcraftv20.com/gallery/albums/MJ-hide/Iphone201205.jpg
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  #9  
Unread 09-10-2006, 08:24 PM
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Default Re: SKOOLS - rebuild advice needed

Quote:
Originally Posted by reelapeelin

Isn't that odd that all six were 95 and now all six are 75??...
??? ...
Was the same gauge used both times? Was the engine cold one time and warm the other? Just a thought.
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  #10  
Unread 09-10-2006, 08:24 PM
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Default Re: SKOOLS - rebuild advice needed

Quote:
Originally Posted by reelapeelin

Isn't that odd that all six were 95 and now all six are 75??...
??? ...
Was the same gauge used both times? Was the engine cold one time and warm the other? Just a thought.
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