Crank cracking

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Oyster 49
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Joined: Tue Oct 26, 2010 6:55 pm
Location: Derbyshire, UK

Crank cracking

Post by Oyster 49 »

I'm decided to strip and clean up the 1969 ish wipac 102 I'm taking to the Hayling bash as back up to H-A's engine. Upon stripping found it to be in good order apart from the crank. Their is a crack running around the web from one weld to the weld at the other end. The 2 sides will move together and thus close the crack :o

Has anybody seen this before? I'm loathe to reuse it without perhaps a blob of weld across the crack and redressing.

The good news is that I have a crank from a 1974 WSPCL that has a terminally cracked block, so is a good source of spares. The crank from the century looks identical both in looks and dimension.

Can anybody advise if the cranks are the same? Also are the con rods the same? I'm not that well up on centuries as 102s are my engine of choice :D Proper seagulls!

thanks.
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102 crank on the left, century plus on the right
102 crank on the left, century plus on the right
Cracked crank webs on the 1969 102
Cracked crank webs on the 1969 102
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John@sos
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Re: Crank cracking

Post by John@sos »

Yes I have seen this on many 102cc motors.

The welded on counterbalance weights have the weld ground off to smooth the eges off and sometimes it leaves little meat. Have found one crank with just one counter ballance totally missing, the owner said it vibrated a bit! I bet!

Most 102cc motors have interchangeable cranks, just watch out for the length of the upper part with the taper, some early ones were a tad shorter.... still fit, just have to be careful to get the flywheel nut on OK!

Am trying to find time to make up a model 90 as second motor for Hayling, see you on the water!

John
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The Tinker
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Location: Whangamata, New Zealand

Re: Crank cracking

Post by The Tinker »

A little TIG weld will sort it. I have welded them no problems at all.
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Rex NZ
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Re: Crank cracking

Post by Rex NZ »

Maybe a little gouging prior to welding would be a good idea
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Oyster 49
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Location: Derbyshire, UK

Re: Crank cracking

Post by Oyster 49 »

Thanks gents. I have rebuilt the power head using the century crank, it all fits nicely. I will get the cracked one welded and I can then dress it back and hold it as a spare. This 102 will go to the ball!
Horsley-Anarak
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Re: Crank cracking

Post by Horsley-Anarak »

I could always drag this one out of the shed :wink:
102.jpg
102.jpg (45.39 KiB) Viewed 665 times
This has been round Hayling already, and done Lerryn 3 times. :)

H-A

P.S. And it went for a swim after I was in the pub in Lerryn with Timberman, got the water out of it then it got me back to Fowey with a new plug. :D
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