freshening up my 350 (1986)

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Jeff w Ashworth

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Jeff
Truck Year
1984
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GMC
Engine Size
350
Well here goes, Tore apart my 350 to freshen it up, honed the cylinders, new cam bearings and cam, new rings, main and rod bearings, polished crank shaft and put back in the block with new bearings and turns free, cleaned up pistons and ring groves, put ring on and in stalled 1 in it's cylinder and new rod bearings, piston drove hard into cylinder (socked in oil) hoked up to crankshaft and wont turn but you can feel it want to go back and fourth but won't turn, rings drug hard down the cylinder. any and all help is appreciated. Thank you.
 

85K304SPD

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K30
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383
Wrong rings or bearings. Maybe some trash in the ring grooves. Something...
Pull that piston back out and figure out why it it tight.
 

Jeff w Ashworth

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I ran a ring grove cleaner around them till I saw the piston shine in the grove. and I also put a rring in the cylinder and checked the end clearance on them.
 

Bennyt

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Oil ring spacer came out of the rails I think.
 

fast 99

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Yes, be sure ring groves are completely clear of carbon. If grove tool is unavailable break an old ring, grind the jagged edge flat.
 

Jeff w Ashworth

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I tried the break a ring in half and I couldn't get them clean enough, so I ordered a grove cleaner and scraped them shiny, the ring compressor looks to pull down flush and good, this is the first engine I have ever had this problem with and I have worked on quit a few in my years.
 

Bennyt

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I tried the break a ring in half and I couldn't get them clean enough, so I ordered a grove cleaner and scraped them shiny, the ring compressor looks to pull down flush and good, this is the first engine I have ever had this problem with and I have worked on quit a few in my years.
That's why I think its an oil ring issue. I've had those spacers pop out of the rails once or twice in my life and jam up and/or a rail fold over.

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