3B crankshaft salvageable? (1 Viewer)

RufusTheDufus

SILVER Star
Joined
Jan 9, 2008
Messages
2,786
Location
Moronville, ME
Visit site
I recently had an engine failure that resulted in 3 main bearing caps cracking with one of them launching through the side of the block. Looking at these bearings and crank journals it's obvious I did something stupid and it resulted in a bunch of debris in the oil system. Do you think this crankshaft can be saved with machining? I can't feel any of the ridges with my fingernail.

PXL_20210717_155110523.jpg


PXL_20210717_155117942.jpg


PXL_20210717_155121575.jpg


PXL_20210717_155212774.jpg


PXL_20210717_155218270.jpg


PXL_20210717_155221185.jpg



This is what the bearings look like. The middle main bearing spun.

PXL_20210717_154812795.jpg


PXL_20210717_154818440.jpg


PXL_20210717_154822370.jpg


PXL_20210717_154827756.MP.jpg



I have another 3B that's got a broken crank. Hoping this one might be salvageable. The closest shop to me that can machine crankshafts is 2 hours drive. That's why I'm seeking opinions before I spend 4 hours in the car.
 
Joined
Jul 2, 2021
Messages
15
Location
Australia
Visit site
It dosnt look to bad IMO looks just like its picked up the white metal that the main and big end bearings are made from and may clean up easily (without machining) Does the shop your looking at have an email address? you could explain your situation and send them the photos of the damage and ask for their opinion, also if you were to machine they would need to know what sizes, so you need to have a part number and size for oversize shells so they can machine to.
 
Joined
Jul 2, 2021
Messages
15
Location
Australia
Visit site
You could also clean up yourself with some fine wet and dry grab some new factory size shells and installs the caps to block with plasti-gauge and check the clearances that way
 

RufusTheDufus

SILVER Star
Joined
Jan 9, 2008
Messages
2,786
Location
Moronville, ME
Visit site
I have the specs from the 3B factory service manual for the machine shop.

As for the shop, they have a "contact us" form on their website but no public email address. I just pulled the crank this morning. The shop isn't open today. I'll call them on Monday, explain the situation and ask of I can email them a photo-sharing link to these photos.

I didn't think the journals look terrible, but I'm far from an expert.
 

RufusTheDufus

SILVER Star
Joined
Jan 9, 2008
Messages
2,786
Location
Moronville, ME
Visit site
I dropped it off at the shop today. They said it looks like they should be able to clean it up but won't know for sure until next week. Their shop foreman that handles all the crankshaft work is on vacation this week.
 

RufusTheDufus

SILVER Star
Joined
Jan 9, 2008
Messages
2,786
Location
Moronville, ME
Visit site
I picked up the crank from the machine shop yesterday. The ridges were bearing material that fused to the crank journals. It polished up and did not require grinding to an undersize. They also verified it's straight. The main bearing journals were at the upper end of the spec. Looks like I'll be rebuilding a 3B this winter.
 

Users who are viewing this thread

Top Bottom