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tomlamb · 06-27-2009, 09:39 AM

No new photos, but renewed frustrations with the junk yard where I got the motor. The 6.0L they got in for me all of a sudden they want an additional $3,000 for and I can't afford it... This is after waiting for weeks for the promised replacement so now I have to try to get my money back from these guys and find another motor or have a shop look at the existing 5.3L. The shops I have spoken to want $200 just to look at it so I need to get some ideas of what it might be.

Does anyone have any insight as to why a roll over 2008 5.3 would have a tight spot when rotating the crank a full revolution? We are rotating it without the plugs and it gets very tight in one area of a 360 degree rotation. Now for the strange part, if you are turning it with a ratchet and can get some momentum before the tight spot it will glide past it, but if you turn it slowly it takes a fair bit of force to get past this spot. When I say a fair bit of force, the starter cannot start spinning the motor if it lands on the tight spot without the plugs in. The yard told us to try spinning it with oil in the pan in case some rust developed in a cylinder and we did, but no change, the tight spot is still there and appears the same. I wouldn’t think it would be a valve because a single valve wouldn’t open on every 360 degree revolution so would that mean lower rotating assembly? Any of you have any ideas what it could be? If I have to replace a rod, pin, or piston would I have to have the entire rotating assembly re-balanced?

06-27-2009, 09:39 AM	#58
tomlamb Registered User Join Date: May 2008 Location: So Cal, CA Posts: 185	Help... No new photos, but renewed frustrations with the junk yard where I got the motor. The 6.0L they got in for me all of a sudden they want an additional $3,000 for and I can't afford it... This is after waiting for weeks for the promised replacement so now I have to try to get my money back from these guys and find another motor or have a shop look at the existing 5.3L. The shops I have spoken to want $200 just to look at it so I need to get some ideas of what it might be. Does anyone have any insight as to why a roll over 2008 5.3 would have a tight spot when rotating the crank a full revolution? We are rotating it without the plugs and it gets very tight in one area of a 360 degree rotation. Now for the strange part, if you are turning it with a ratchet and can get some momentum before the tight spot it will glide past it, but if you turn it slowly it takes a fair bit of force to get past this spot. When I say a fair bit of force, the starter cannot start spinning the motor if it lands on the tight spot without the plugs in. The yard told us to try spinning it with oil in the pan in case some rust developed in a cylinder and we did, but no change, the tight spot is still there and appears the same. I wouldn’t think it would be a valve because a single valve wouldn’t open on every 360 degree revolution so would that mean lower rotating assembly? Any of you have any ideas what it could be? If I have to replace a rod, pin, or piston would I have to have the entire rotating assembly re-balanced?