Other Broke Crank at the Flywheel. WTF?
- Thread starter tshank123
- Start date
- Location
- Hamilton Ontario
I work at a small engine shop, We had a Toro Lawnmower break a crank like this and they covered it under warrenty as a faulty casting.
Freakrider
X247
- Location
- Tampa Bay area
Feel for ya, I once had an oem crank only 1.5 yrs on it and big pin snapped on a 701....sux !
High Speed Industries
Your one stop shop for quality parts @highspeedind
- Location
- Lake Havasu City, AZ
Did you do that yesterday at govt wash? What crank is it? Oem?
Yea, happened yesterday. This is embarassing, but here goes. Its an SBT. I got the crank new in a package deal when I bought the donor 1200 boat. I actually sent the crank to Competitive Crankshafts and dropped $200 on it to have it inspected and rebalanced etc (and this was a new crank). I felt comfortable running it at that point. If anything would of failed, I thought it would have been a bearing. I also thought that this portion of the crank was OEM, even if it came from SBT. I dont know though. Maybe somebody knows?
#ZERO
Beach Bum
- Location
- Florida - U.S.A.
You should have been using a lightened & balanced 1200 65U flywheel to keep the rivets from vibrating loose which would have considerably less stress on the crank snout from that heavy flywheel but over torqueing the crank bolt is also the major contributor.
I torqued it to spec, but who knows if it was ever overtorqued in the cranks previous life. If the rules in my class would have been different, I would have had it lightened already. They changed the rules this year, so you'll be getting my flywheel at some point.
High Speed Industries
Your one stop shop for quality parts @highspeedind
- Location
- Lake Havasu City, AZ
I don't think it's your fault it broke. I saw it today. I'm surprised the flywheel didn't damage some other parts.
- Location
- baldwin ny
stock rev limiter? i would b suprized if it was.
Flash-FX
No Square..No Round..FX-1
- Location
- South Jersey Shore
I had the same thing happen to me but with a aircraft crankshaft (hmmmm,what's that little vibration???). Just made it back to the airport...
On disassembly/inspection later that day, while I was prying out the key with a screwdriver, the nose of the crank (where the hub for the prop mounts) came off in my hand. It looked just like that......I was lucky.
No warranty on crankshaft.
On disassembly/inspection later that day, while I was prying out the key with a screwdriver, the nose of the crank (where the hub for the prop mounts) came off in my hand. It looked just like that......I was lucky.
No warranty on crankshaft.
Blue
Judging your cheapness
- Location
- St Cloud Florida
Its unusual for a crank to break at the flywheel but it does happen. Typically caused by metal fatigue and stress as everytime the ski comes out of the water and free revs then the pump reloads with water slowing the engine very rapidly meanwhile the 3-4 pound flywheel still wants to keep spinning. I'm suprised it didn't just sheer the keyway.
No, stock rev limit on a GP1200 motor is 7050. I have the Protec Mod which sets it to 8100. Its pretty much mandatory when running a 144 pump.
I'll definitely be sending the flywheel to #zero. The lighter flywheel plus balancing should hopefully keep it from happening again.
Actually, I think the stator might need replacement. I'll try to repair it but not sure if its salvagable.