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Old 14 June 2014, 12:30   #41
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Looks great!!!
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Old 14 June 2014, 14:51   #42
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Looking good.

I'm up last two weeks of July... If I see you I'll race you. No doubt you'll win... but only because I'm going half throttle!
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Old 15 June 2014, 12:49   #43
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Cheers,

Sounds good to me, you never know - if I end up upside down you could win!

Had a look at the carbs this morning, lots of measuring and testing later this is the end result -

Maybe not a "bolt on" modification after all...

Got everything back on the engine, a lot of pulling over (not easy with this compression!), and IT RUNS!

A wee bit lumpy just now, needs tweeking to get it running right. Tried to find the size of the main jet by seeing which drill bits would go through the hole. 1.3mm will go through but 1.4 won't. I assume this means it has 135 mains?

IMG_2552.mp4 Video by Roflhat | Photobucket

Lots of smoke due to the 2-stroke oil we used during assembly.
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Old 15 June 2014, 13:09   #44
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On that engine all main jets are not same size, upper and middle should be same, lower bit less. Don't fiddle with jets on a standard engine.

Happy Boating
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Old 15 June 2014, 17:26   #45
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Quote:
Originally Posted by Locozodiac View Post
On that engine all main jets are not same size, upper and middle should be same, lower bit less. Don't fiddle with jets on a standard engine.

Happy Boating
Alright thanks for that. I had to switch the top and bottom carbs over because the throttle cam on the tohatsu is on the top carb, yamaha was on the bottom.
It's not a standard engine.

Cheers
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Old 17 June 2014, 08:42   #46
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The barb I was waiting for finally arrived so I got my fuel pump setup.

Made up a plate so I could mount the pump using two bolts instead of relying on one.

Got the boat launched to try it out and immediately had problems. The ground wire for one of the coils had snapped. So 15 minutes later that was fixed, took it out for a blast, was very slow getting on the plane, the all of a sudden the power is just there and it takes off. Couldn't really open it out, bit too windy. Managed 48 knots, not a personal best but not bad for the conditions. Highest RPM I saw on the tach was around 6100, so hopefully there's plenty more in it.

Idling very low just now, need to sort that out first then see how it goes. I'm hoping the acceleration bogging problem can be fixed by changing the carb jets?
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Old 17 June 2014, 11:34   #47
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Did you set up the timing?
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Old 17 June 2014, 11:59   #48
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Did you set up the timing?
I've not done that yet, do you think that could be the problem?
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Old 17 June 2014, 12:13   #49
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My thundercat

Possible.

I'm just wondering how you will do it, didn't you cut the ring gear off the flywheel? Timing marks are usually on it.
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Old 17 June 2014, 13:59   #50
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Originally Posted by A1an View Post
Possible.

I'm just wondering how you will do it, didn't you cut the ring gear off the flywheel? Timing marks are usually on it.
Yeh I cut it off. I'll look into this, it's not something I've done before. Is it a matter of adjusting it, testing it, adjusting it? Whats the best way to go about doing it?
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