9.9 4 stoke crankshaft

billdy

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Hi I recently pulled my yamaha 9.9 4 stroke extra long leg high thrust completely down. Mainly just to check it. I did put in a stainless pivot shaft to eliminate lock down lever sticking. Now it keeps going to run on one. It might run on two for a while.

There are two things that are confusing me.

1) The crankshaft has about 10 degree play. In other words I can rotate it back and forth that much with no resistance. The fly wheel is tight. How can that be?

2) I have check all the species for the electrical, side new pugs etc. All ok except my multi meter shows .9 ohms across the input (orange and black) on the coil. The manual says it should be between .26 and .35 ohms.

PS Stripped carby and that seems fine.
 
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99yam40

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So it should be a T9.9
bad rod bearings or piston pin maybe.
have you check to see what your meter leads resistance is?
 

99yam40

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so if it reads1.0 when touched together ,how can you measure .26 or .9 ohms
 

billdy

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so if it reads1.0 when touched together ,how can you measure .26 or .9 ohms
Well I am only remembering that from yesterday when at the boat so not that sure. I might head down there. Don't multometers always register no resistance when you touch the leads together?
 

billdy

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Well I am only remembering that from yesterday when at the boat so not that sure. I might head down there. Don't multometers always register no resistance when you touch the leads together?
Actually your right. One mmeter says
0.6 and other one says 1.7
 

billdy

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billdy

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so if it reads1.0 when touched together ,how can you measure .26 or .9 ohms
On checking again it's 0.6 on one and 1.8 on other.
 

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99yam40

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yep when trying to measure small resistances always measure lead resistance and subtract it from the actual reading.
they use small flexible wire in the leads of different lengths, so no way they will be 0
 
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