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hammer crankshaft broke...

Old 11-27-2005, 02:28 PM
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Default hammer crankshaft broke...

this is what happen when ur running in an iced pond,,just kidding......i can't believe i broke it, by the way, i play it really hard, too much rev. and cavitation, the hammer literally get airborne during acceleration, jumped 4-5 times, lots of fun before it went bad...got a video clip but in some way i can't upload it...

question, do i need to open the engine during replacement or i can just reinsert it after taking off the pull starter?...anybody there?,,,thanks.
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Old 11-27-2005, 08:21 PM
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Default RE: hammer crankshaft broke...

just get a new engine that can stand up to the stress
Old 11-27-2005, 10:01 PM
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Default RE: hammer crankshaft broke...

OOPS! You're going to have to tear the engine pretty much completely down. Do yourself a favor and mark the connecting rod before you remove it so that it goes back in the right way. It broke at the weakest spot of the crank, right where the air/fuel mixture goes in.
Old 11-28-2005, 09:28 AM
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Default RE: hammer crankshaft broke...

That's a common failure if the sharp corners at the crankshaft inlet port are not blended to a smooth radius. Without the corners blended, you have a stress concentration point that say's "break here".
Old 11-28-2005, 07:45 PM
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Default RE: hammer crankshaft broke...

need help pls..anybody can tell me step by step???

how to remove the piston from the crankcase??

look at my cylinder head water cool,,is this normal to have an adhesive(red thing) or it's a deposit? thanks in advance..
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Old 11-29-2005, 12:01 PM
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Default RE: hammer crankshaft broke...

That's red RTV. Did you buy the set up new or used? The only reason there would be any kind of sealant in that area is a leakage problem. If you bought it new, it tells me the manufacturer has a problem with machining the parts flat enough. I have never seen RTV used in a cooling head from the factory, but then again, I've only owned OS, K&B and HB. Come to think about it, I've never seen it used in Pico or OPS either.
Old 11-29-2005, 08:27 PM
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Default RE: hammer crankshaft broke...

do yourself a huage head ache preventer and make shure all of the bit and fragment and shvings of that drive shaft are out of the engine casing or you could cuase more problems like breaking more stuff or just wearing your engine out faster
Old 11-29-2005, 09:43 PM
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Default RE: hammer crankshaft broke...

WOW!!! I have never seen that happen Wakka!
You must really give your boats some curry.
Is that common place these days with the newer engines?

Seems to me the manufacturers are skimping on quality to increase their profit margins.
An engine should be capable of handling everyday use. If you drove the boat up onto dry land with the engine at max revs, I could understand it, but that does not seem to be the case.
As said before is that engine second hand or new.

As for removal of the piston, if you remove the sleeve, push the crank rotor against the front engine bearing and pull the conrod toward you the piston will come out.
Sorry to see that happen to you mate.

Regards Brettos.

ORIGINAL: wave waker

this is what happen when ur running in an iced pond,,just kidding......i can't believe i broke it, by the way, i play it really hard, too much rev. and cavitation, the hammer literally get airborne during acceleration, jumped 4-5 times, lots of fun before it went bad...got a video clip but in some way i can't upload it...

question, do i need to open the engine during replacement or i can just reinsert it after taking off the pull starter?...anybody there?,,,thanks.
Old 11-30-2005, 12:12 AM
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Default RE: hammer crankshaft broke...

If the piston is a tight fit at the top, sometimes all you have to do is push the piston upwards. The other trick is to inset a popsicle stick into the exhaust port then push up on the piston. Most of the time it's easier to remove both the piston and sleeve when tearing the engine down.
Old 11-30-2005, 06:21 PM
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Default RE: hammer crankshaft broke...

yeah! it's a brand new engine 4 months old, just 1 month after warranty happened,,not good...

thanks guys for all the info... i was able to pull out the piston and crankshaft, waiting for the order to come..
Old 12-01-2005, 09:03 AM
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Default RE: hammer crankshaft broke...

Make sure there are no sharp corners on the replacement crankshaft. I shouldn't even say that because there will be sharp corners in the inlet port. Use a round jewelers file and blend out the corners. It does'nt have to be a large radius. Just get the sharp edge out. Then polish those areas so you end up with a surface finish that has no machining or file marks. If you aren't capable, or confident you can do that, then find someone that can do it for you. It will add life to the shaft with the benefit of a smoother flow through the port..
Old 12-01-2005, 06:05 PM
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Default RE: hammer crankshaft broke...

Good news guys got my new crankshaft, install tonight but i do no when is the test run gonna happen..snow, freezing rain is goin on.[]

Hey John P., i want to try smoothing edges, thus dremel will work??.. is it the outer edge of the port needs to smooth?..thanks
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Old 12-02-2005, 08:59 AM
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Default RE: hammer crankshaft broke...

Based on what I see in the photos I'd concentrated on the rear side of the port at the ID corners. The port now looks like it was cut out with an axe but the rear ID looks like it is pretty sharp. You can see that the old shaft failed at those corners. If you look at the fracture surface with a high power glass you'll probably see origins in the ID corners (looks like small waves - striations - originating in those corners and progressing outward).
Old 12-02-2005, 10:34 PM
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Default RE: hammer crankshaft broke...

thanks John P. and all, got my engine built and firing, just waiting for a good weather timing for test run.

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