Im just wondering if i need to get my crank hardened, when they ground it they took 5 off the mains and 10 off the rods, he suggested getting it hardened motor is out of a komatsu pc50uu-1 3 cylinder engine, thanks for input in advance
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crankshaft hardening
- Thread starter samsstuff
- Start date
bearing got one journal but he turned them all
John C.
Senior Member
I wasn't aware you could precision harden a cast iron crankshaft. I do remember some years ago Cat called for shot peening the radius areas on the main journals of a D9 engine in some applications. Do you have a Komatsu engine or a Yanmar?
Walker1
Well-Known Member
I have rebuilt a wide variety of motors and have never heard of it. I would bet that if you drive downtown, simply ask some of the girls loitering around if they know of anyone that can harden your crank. I bet they might know a few people who could for a relatively good price.
Continental Engines in Memphis, TN used to do a Tuffriding process on some engine shafts we had them rebuild. Here is a link describing it.. Do not recall the deciding factor as they regularly turned Y112's and F 163's 70 10 or 20 routinely. Cost was modest and never knew good or bad from doing it.
John C.
Senior Member
Interesting thread. Buck knives does nitriding to there blades.
I thought the last post was a little off Kilter though. I'm paraphrasing here, seen cranks go 100,000+ miles and looked new because of the treatment. Here's a cheaper way to see the same thing, change your oil every 5,000 miles.
I thought the last post was a little off Kilter though. I'm paraphrasing here, seen cranks go 100,000+ miles and looked new because of the treatment. Here's a cheaper way to see the same thing, change your oil every 5,000 miles.
Truck Shop
Senior Member
Honda for years has used the nitride process, pretty common.
Most diesel engines use a forged crank and are easier to harden than a cast crank. They are likely to be induction hardened when they are made. Or maybe nitrided. As far as i know, shot peening, especially in the fillets(radius) would likely be more for stress relief because thats where a crank is most likely to crack or break. Some cranks are not recommended to be reground because the hardening is quite thin but it depends on the manufacturer and how much is ground off. Specialty crankshaft rebuilders can pretty much do anything to rebuild a crank- it just depends on cost effectiveness, etc. Small engines may have shallower hardening than larger engines, again depends on the manufacturer. Hardening can make stuff brittle-- thats why they are not hardened all the way through, just for better bearing wear at or near the wear surface. When a main or rod throw is burnt black from a bearing failure, likely most or all of the hardening on that journal is gone
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Truck Shop
Senior Member
nitride cranks only have a depth of hardening .007.
It's a komatsu, I think it's 3d95, have go back look at model number on motor
Yep I'd say they could fix u right up, for small fee
Never driven a excavator 5,000 miles, that would be interesting
Walker1
Well-Known Member
Not even sure what king of MPG one would get.
TriHonu
Well-Known Member
Contact Crankshaft Supply in Minneapolis. They have the capability to anneal and harden crankshafts.
kshansen
Senior Member
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Sorry I'm late to reply but I think there is a typo there, should be GPM!
took it other day, i think they told me they were going to nitride it, afraid to het it because of not knowing metal type, ill be glad get that thing back running, i miss that dirty little hoe