10-19-2007, 07:11 PM #1
My crazy crank problems continue.
This happened a while back but I thought I would post just for informative purposes.
Started end of summer, all of a sudden at idle the engine was making a clanking noise. Anything but idle and no more clanking noise. Ski still ran fine, great power. Shut it down and up on the lift. I only ran it making this noise for about 5 minutes before I put it up. Came back 2 weeks later to see if the problem was still there, yep it was. Clanking at idle but fine otherwise. About 5 min into the ride the ski locked up and wouldnt start back. Felt and sounded like a seizure. Hoped off the ski and swam it back to the dock 200 yards away.
Got it on the lift, peaked in the hull and there I saw the entire contents of my oil tank under the motor and I could still hear the spewing sound of oil filling the hull. Shit, oil line came off and I seized the motor, and screwed the crank bearings (clanking noise I was hearing) right?
Let the ski sit for a good month as I was too pissed to mess with it as I had just rebuilt the motor with a brand new OEM crank because a month before the #1 crank journal snapped right off my crank.
Finally got to taking the ski apart. First order of business, turn the driveshaft. Terrible clank noise when doing this, bearings right? Next step take the head off. Got it off and everything look perfect, cylinders look great too. Hmm usually the cylinders go before the crank I was thinking. But I guess my in this case the bearings locked up or something. Remember the clanking noise I was hearing, crank bearings from no oil, right?
Got the U pipe off the motor so I could get to the oil pump. To my shock the oil line to pump was still on, no problem there. Started taking the oil pump off and I got one bolt out. The other bolt was giving me a hard time. Got off and the oil pump, in TWO parts, feel into my hands. The oil pump was split down the middle! The spring and fitting (for the crank bolt) had literally being knocked through the oil pump splitting it in half. So the snout broke off and sent the end through my pump, right?
Next step, pulled the motor. With the front cover on and looking into the hole where the pump went, while turning the coupler, the bolt was turing but off balance, hmm?
Pulled the front cover and SOB there sit the flywheel magnatized to the stator. The flywheel bolt backed out and the flywheel came off and slammed into the pump, cracking it and sending oil into my hull, not the motor. Great so motor is still screwed right?
Nope, with the front cover off and the flywheel out to stop beating around, I turned the couple and everything moved butter smooth. Not a single hitch, noise, clank, nothing. The freaking motor is fine, after going with with no oil, for obviously not a very long time thank god.
So sweet, lets just bolt that flywheel back on and put the motor back in. Wrong, the bolt had backed out but I guess there isn't enough room in the front housing for the bolt to come completely out of the crank snout. Thus while the motor was turning last 2 threads of the bolt were riding in and out, spinning in the snout threads. This resulted in stripping the first couple of threads in the snout and leaving other threads jammed with metal shavings. The bolt (a new one I bought since the old one was stripped out too) would not screw into the crank. This is not good because that snout is some extremely hard metal.
Called around and found a machine shop. Figured out it was a 10x1.25 tap and the guy started away. He couldnt even get it started because because the metal was so hard and it was stripping the tap out. After some thinking we decided to try and drill out the messed up threads. He tried a couple bits and nothing. He brought out one last bit and said if this doesnt cut it, nothing will.
Thank god it worked. He was able to open up those bad threads just enough and clean out the hardened shavings that the tap would get going. Problem was the crank metal is so hard that it was difficult turning the tap, he said it felt like too much force and that tap was going to break off inside. Thankfully only a couple threads were bad so he was able to go deep enough with the tap that everything worked out. The bolt now goes it perfect. The machinist said this was some of the hardest metal he has ever dealt with, he called it "NASA space shuttle metal" haha .
So anyway, that is the story. I thought it was interesting and I would share. Motor will be going back in this weekend. On a side note I decided to sell the ski. I'm going 4-Tec I've already parted out the major speed parts and now im just going to put it back to mostly stock (heads, modded carbs, jetworks, FF, and a few other things still remain) and sell it. So if anybody is looking for a good GPR, look no further. The hull is FAST, it has a brand new crank, and it is one of the cleanest boats you will find. hehe, enough selling that is for another day.
Thats the story, damn crank!
10-19-2007, 07:19 PM #2
Nice story with a happy ending for once.
10-19-2007, 08:51 PM #3
- Join Date
- Apr 2006
- panama city beach 'fl
10-19-2007, 09:02 PM #4
If you need a hand, give me a call..... look forward to going riding in a couple weeks when you get it back together
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