#2 500 rpm drop

by Wendell Hamilton in General Tech Discussion 8 years ago

Recently puchased Coyote ii, (500 rpm mag drop on #2 mag @ 4000rpm) they were replaced a year ago with 966729 modules. My question is: what is the other # stensiled on module? Ie, 14.7156 and 14.2653. The a/p told me to switch the lower connectors , no simple task, and see if #2 mag switch off still dropped and if new plugs did not solve issue and give him a call. Plugs did not help. There is a noticable miss but not a violent roughness during mag #2 mag switch closed. Any information will be greatly appreciated that might save me $100.00 an hour And a $1000.00 smd module.
Wendell

Re: #2 500 rpm drop

by Glen Marshman » 8 years ago

Glen Marshman

1 2 0

Great Question,
Had the same issue. We switched the connectors on the modules from circuit A to B. No change. Checked the caps for resistance all in spec. No change. Replaced all of the plug wires. No change. All of the grounds are in place. Worked with 2 different certified Rotax mechanics. They had no clue. The certified mechanic sent the modules to Lockwood to check them out. No word yet.

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Re: #2 500 rpm drop

by Wendell Hamilton » 8 years ago

Wendell Hamilton

3 2 0

Glen
that is discouraging. The A/P is waiting for new modules to come in so we can see if the new one makes it go away. At $100.00 hour this could add up pretty fast. Let me know what your solution ends up being.
Wendell

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Re: #2 500 rpm drop

by Wendell Hamilton » 8 years ago

Wendell Hamilton

3 2 0

Finally 500 RPM drop problem solved thanks to Rex Johnson A/P of RJ MechanicAl at KRVS tulsa Ok. He told me all the things I could check which was basically what we discussed on line. Having ruled out the ignition modules, plugs and spark plug wires, carb balance I took it to Rex. He felt the timing was off and went straight to work on the trigger coll adjustment. Even though mine will not align perfectly he was able to balance the two and fixed my huge mag drop on #2 mag. As I watched him tackle the problem he gave me several pointers of things I should change to improve my assembly when I'm doing my general maintanance.

Thank you said by: RotaxOwner Admin

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