Crank has me all cranked up

[eaw46]

I am stumped I have a 43 GPW that had a froze motor when I bought it I had it rebuilt and the crank bearings looked like they had been oil starved we had to go 6
0 over and did everything all new and put it back together. Put 500 miles on it ran good used the right oil was doing the right break in process and all was well. Took it out this spring for a short run temp was good 30 psi on the oil gage and bang stopped dead. Took it apart and all the main bearings are scored just like the last time. Now I need a new crank and need to stop this from happening again. Looking for ideas and help. Where can I get a crank for a reasonable price and what do I need to look at so it does not do this again. Thanks Eddy

 

[rtk]

Usually when the bearing wear prematurely , I would look at contamination and or oil starvation . Did you hot tank the block and check all the oil passages ? Is it just one main bearing/rod bearing ? all of them ? . IMHO 60 over cut to the crank is a lot .Did you line bore the block ? Sorry to throw all of this at you , but I am just trying to give you some ideas . Did you use a new oil pump ?

 

[eaw46]

New oil pump. I do not know if they line bored the block or not it was done at a local shop that does very good work but mostly on competition motors for dragsters. All the bearings look scored but only the first is really bad. 60 over is where we had to go as it was scored last time too. They did hot tank the block but again I do not know about the oil passages check.

 

[rtk]

If you could post a few pictures of the bearings , it might help . Hot tanking the block is very important as well as making sure the oil passages are CLEAN . I would look for a new crank , check your rods and mains and line bore your block . BTW , it sounds like what ever happened started at the that first bearing , rod or main bearing ? Off the top of my head , I am not sure where you oil feeds from , but look at the TM it will show how the oil feeds and you can get a pretty good indication of how this happened . good luck bob k

 

[eaw46]

Here is the crank and block. Eddy

 

[bigbird1]

Looks like oil contamination, you can see the radial marks where the junk followed the oil around the crank. Be sure to check the rocker tubes they can hold lots of junk.
take it to a good machine shop they can build it up to stock size for you, we do it all the time.

 

[rtk]

Agreed , sure looks like something got to those bearing journals . If it were my engine , I would hot tank the block , head and crankshaft , line bore the block , re-size the rods and perform any other machine work and reassemble . Your next problem would be to find a good machine shop .