6.2 383 cranksaft
 

Which crank would you use,
Stock Merc 6.2 crank, Are these internally balanced?
Or Scat cast crank?
Trying to start collecting parts.
Thanks for your input.

Fixx
 

if its a budget engine look into the scat f43 light weight crank..

http://www.scatcrankshafts.com/press_releases/F-43.html

if your going for a all out stout crank then winberg..

http://winbergcrankshafts.com/

so, avoid the eagle stuff?

Just my opinion. For the nominal difference in cost bewteen a 383 SBC cast or forged crankshaft I think you are way ahead staying with the forged crankshaft as a base building block of your new planned engine.

Best Regards,
Ray @ Raylar

The stock 6.2 crank is a nice forged piece. Originally made by Lunati, but not sure on the later engines. They are internally balanced. If you have one of those, keep it. Otherwise spend the money on a quaility forged crank.

Bob Lloyd
Full Throttle Marine



.

Thanks Bob and Ray, thats what I needed!

The later (6.2 Horizon) is not a good unit. I had one break in half at 4200 RPM in a pleasure boat. Engine was never apart and was not a hi performance boat running hard. When we took it to the local crank shop the owner said he had seen several like it.
Good parts make good engines!
Steve

Interesting.

Miklos, I have 6.2 MPI's with over 200 hrs on them. They're 2003 models.I think they have the forged cranks.What year was the one you had issues with?
Thanks,
Attila

On top of that,,,what is the difference between Horizon and Mercury, did a search no info that I could find. This thread is turning out to be very informative IMO.

Mercury did change crank mfg along the way. I know the early cranks were Lunati (it was stamped). Later models were not stamped with any mfg name and the Merc part number changed. However it is still a forged crank in all 6.2 engines. It's also the same crank used in the 383 Mag that Merc sells. I've built several with blowers and they've been running for years, turning 6000 rpm.

Not sure what Steve ran into on the Horizon engines, but they should also be the same crankshaft.

Bob Lloyd
Full Throttle Marine

Good to know Bob!

I've bought the last 20 cranks Lunati had. 1 pc rear seal 4340. 3.75" Stroke. 100% USA made. I have 3 left.

I have the crank already, Do have a friend looking though.

Horizon is Mercury inboard high durability line. We took the crank to Steve's custom's crankshafts well known shop in Tampa area. He said it was chinese and he had seen several fail out of boat engines. I think engines are 2005. When the crank went it took block etc. I am very sure it is not a lunati part, perhaps the blue motor was? I was really surprised to see this failure as GM parts are usually more than adequate if used within specs.

Steve