wrist pin bushings gone
#1
wrist pin bushings gone
Got a 2000 7.3l out of a fedex truck in the shop. It was hammering when it came in. Yanked it out and pulled it apart. Found a wrist pin bushing completely missing and connecting rod end egg shaped and the valves hitting the piston. Got to inspecting the rest of the cylinders and I can see where the valves have come in contact with the pistons on a few of the other cylinders. Found loose wrist pins on those rods also. I checked to see if the piston coolers where intact and appear to be pointing in the right direction. Engine ran great had great oil pressure. Oil was a good condition and not thinned out. Engine has about 120k since it was replaced with a International crate motor. The one thing I don't like is the owner serviced his oil every 10k miles sometimes 15k.
Thats the story now here's my question: Cylinders look good except the one with the wrist pin gone. It will have to be bored and sleeved. It's .040 over now. Cam appears to be in good shape. I tested the valves and they are not bent and no damage appears to the heads. I still want to pressure check them to make sure.What bothers me is the clearance between the valves and pistons. I don't know if someone decked the block and heads to the max limit or what to make the valves contact with just a little wrist pin play. Not sure if this motor is fixable or not. Of course the customer wants to get out as cheap as possible. But I not staking my rep on a crappy job. I'll sit back and listen now Thanks TBJ!
Thats the story now here's my question: Cylinders look good except the one with the wrist pin gone. It will have to be bored and sleeved. It's .040 over now. Cam appears to be in good shape. I tested the valves and they are not bent and no damage appears to the heads. I still want to pressure check them to make sure.What bothers me is the clearance between the valves and pistons. I don't know if someone decked the block and heads to the max limit or what to make the valves contact with just a little wrist pin play. Not sure if this motor is fixable or not. Of course the customer wants to get out as cheap as possible. But I not staking my rep on a crappy job. I'll sit back and listen now Thanks TBJ!
#2
After hanging around here for five-plus years, this is the very first I've heard of a pin bushing having a problem.
Without another, unmodified block with which to compare the one you have, I don't know how you are going to find machining dimensions to compare, though decking a block more than a "clean-up" would be dumb for a "stock" motor.
But you already knew all that.....
Sorry!
Pop
Without another, unmodified block with which to compare the one you have, I don't know how you are going to find machining dimensions to compare, though decking a block more than a "clean-up" would be dumb for a "stock" motor.
But you already knew all that.....
Sorry!
Pop
#4
Thanks fellas. I didn't even consider the weak valve springs. I kinda ruled them out when I found wrist pin play in the connecting rods of the pistons that had valve impressions in them.
As of now were gonna fix the block and put new pin bushings, rods, mains and rings and see where it goes from here. I hope this doesn't come back to bite me in the butt.
As of now were gonna fix the block and put new pin bushings, rods, mains and rings and see where it goes from here. I hope this doesn't come back to bite me in the butt.
#5
Thanks fellas. I didn't even consider the weak valve springs. I kinda ruled them out when I found wrist pin play in the connecting rods of the pistons that had valve impressions in them.
As of now were gonna fix the block and put new pin bushings, rods, mains and rings and see where it goes from here. I hope this doesn't come back to bite me in the butt.
As of now were gonna fix the block and put new pin bushings, rods, mains and rings and see where it goes from here. I hope this doesn't come back to bite me in the butt.
Start by recommending a complete long block and if they balk, then they get to shoulder the risk of only doing a partial rebuild.
That engine was put together with junk wrist pins and it's bored .040 over already!!!
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