Ah. I assumed dropping a valve meant the keepers popped off and the valve fell in the cylinder. What would hurt the crank if the journals look good?
Lost the motor?
- Thread starter danzick
- Start date
I probably shouldnt have said it that way, but it sure looks to me that you broke the heads off the valves which took out the piston. If you did float the valves like we think, the piston wouldve hit them and broke them off. Im shocked at the damage in the other cylinders on that side.
Have the crank thoroughly tested if you decide to reuse it. I wouldnt reuse the cam.
Have the crank thoroughly tested if you decide to reuse it. I wouldnt reuse the cam.
im also curious about that? how did those pieces make it into the other cylinders? through the intake valves?
Yes, pieces probably went up the missing intake valve into the runners and got pulled into other cylinders. I would buy a new stock crank. I seriously wouldn't use anything from that motor. If you cracked a piston I wouldn't think twice about reusing the crank and cam. After seeing that is buy new or buy a complete motor
yeah.. I have the engine completely torn down now. aluminum got into the bearings. the bearings were pretty bad, but the crank does still look decent. I am going to hold onto it just incase, and if for some reason I do need it, I will have it fully checked out and polished, but at the moment, I am on the hunt for a used complete long block. What kind if mileage should I shoot for to not have to really mess with the crank/bearings and heads? I would like to find a good used engine, and do some deliped stock pistons, forged rods, studs, and possibly have the cam keyed. This truck gets about 1500 miles a year, so even if I could confidently get 50k or so out of it before it needed attention again, thats like 20 years for me haha.
with as much destruction as you have, this is one of those "what came first, the chicken or the egg". you can look at all the rest of the pistons for cracks at the lip area and that might give an indication that you have a cracked pistons if more have cracks but again, its hard to say.
Hicksville Auto Recyclers would be a good place to start on the search of a used bottom end. I don’t know if miles would be to much of an issue if your gonna go through it anyway.
Thanks for the tip. I might go look at a truck tonight. It has 300k on it. Guy claims the bottom end has 160k from an 04 lly. Swapped the heads to put in his truck and didn't do the heads right I guess and blew the gaskets. He wants 3k for the truck. It's a beat up pos. Have I lost my mind? Lb7s are hard to find in Montana.
If your into trying to get rid of extra parts 3,000 isn’t too bad. Wouldn’t hurt to see if he takes less. You could probably have yourself what you need pretty cheap by selling the good parts you don’t need.
yeah I thought better of it. Im going to look for another one. ill give that hicksville a call tomorrow. My uncle found one right by him in Oregon with 170k for 3500, but i thought that was a bit much for the miles. plus the 10 hour drive.
I'd recommend trying to find something out of a rust free area if you can. Out here those complete take outs are cheaper but everything on them is usually rotted
Oh for sure. A local yard wanted to sell me a Minnesota engine last week. I declined and he didn't blame me haha. Mt engines are usually pretty good. And according to my uncle the Oregon one is clean.
Yep good people they are at Hicksville. At least your looking a LB7 and not for a LML because they can’t get them done fast enough for the demand.
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Look in Florida for rust free, tons of lb7's down there from farming. LML's were the longest running engine code for Duramax so far, 11 to 18.