Mercury 90hp Elpto Possible Timing Issue?

[dpatterson]

Hi there,

I have a 99 2 stroke 90hp Mercury that seems to be having issues.

When I took it out I couldn't get the engine past about 3000 rpm's under load. (I can put in nutural and it will rev fine).

When I come back to idle it would die out on me. Sometimes I would have to give it gas to get it to crank back up.

Here is what I have done so far:

New Plugs and Wires
Spark Test - All 3 have strong visual spark
Carb rebuild - Soaked and Cleaned Jets
Fresh fuel and Stabil added.


Is it possible this could be a timing issue / link and sync?

When I played with the trigger arm yesterday it started running much better. I have yet to try it under load, but wanted to see if anyone had any other suggestions.

 

[CharlieB]

Re: Mercury 90hp Elpto Possible Timing Issue?

Reving in Neutral doesn't prove much, and can possibly be hazardous if the motor/carbs stick, a very expensive repair.

A good spark test cranking does NOT prove that the high speed windings in the stator are good. This must be tested using a DVA Meter.

A failing high speed winding will limit spark intensity at speed and in effect 'govern' engine speed at WOT, hanging between 2500 to 3000.

Download the FREE Troubleshooting Guide from CDIElectronics.com

Follow their detailed instructions on how to test your stator correctly.

Repost any questions or problems.

Remember, there is NO RETURN on electrical parts, test, test, and re-test again to be certain of your diagnosis before ordering electrical parts.

 

[dpatterson]

Re: Mercury 90hp Elpto Possible Timing Issue?

Thanks for the reply. I took a closer look at it over the weekend. The timing control arm was not sprning back. I loosened the center bolt and now that the linkage is springing the trigger appears to be moving correctly.

I haven't yet to run it but hopefully that fixes it.