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fracture split connecting rods.. re-use?

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 PostPosted: June 16th, 2019, 3:10 pm   
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Are most people re-using fracture split rods?

Are you finding the the fractures re-align properly if the rods are lived a long life?

I'm finding that the caps are a bit expanded, or very slightly deformed, in such a way that they are maybe bowed out in shape. I can feel the fracture edge on the inside of the big end of the rod: both edges of the fracture on a tiny bit wider on the cap, so the big end of the rod is a hair narrower than the cap.. The ridge I can feel is on the rod side on both fractures. Tried to measure the ridge height by sweeping a test indicator, and it may be just 0.001" off, but feeling with my finger nail it is not dead smooth.

I was expecting to not feel a ridge at the fracture. Should be perfectly smooth for re-use, correct? Or have people gotten by with re-using rods with slight ridge at the fracture?

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1989 Voodoo Yamaha 70
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 PostPosted: June 16th, 2019, 7:30 pm   
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Location: Lake simcoe
You are correct that they should be flush with the big half of the rod. Not sure if it would mar the crank at all with the small amount of side to side the rod has on the journal once assembled.

Would this be for your t750 yamaha?


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 PostPosted: June 16th, 2019, 7:39 pm   
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Yes, I want to assemble a second block. New factory rods are WAY too expensive. Looking at WSM, maybe..
Same rods as a Yamaha 3cyl 90hp.

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1989 Voodoo Yamaha 70
1980 Thundercraft v142 Restored


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 PostPosted: June 26th, 2019, 9:55 pm   
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You may be interested to know that OMC has had a special tool for over 30 years to align rod caps with the rod to eliminate this issue.

Matt

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 PostPosted: June 27th, 2019, 8:06 am   
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Interesting, I will look in to it. At one point I thought of putting a clamp on the cap to see if they would squeeze in to alignment.

I have acquired some new rods. They look perfect.

Thanks for this info!

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Delta T750 Yamaha 55
1989 Voodoo Yamaha 70
1980 Thundercraft v142 Restored


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