Still losing power

[VikingRSA]

Hi Guys. My 200HP mercury is still losing power after I cleaned the carbs, the fuel tank, replaced all the fuel lines and primer bulb. Had it dino tuned and repeatedly serviced. it loses power at WOT but only after running for about 15 - 30 min. as soon as I take it back to idle it's fine. I am starting to go mad:% please help!!

 

[JB]

Re: Still losing power

Hi Viking.

To save helpers the trouble of searching out more details on your problem from previous posts, please tell us the year and model of your engine, and any more information you may have.

Thanks.

 

[VikingRSA]

Re: Still losing power

that would help... Mercury 200hp serial number B199460 - don't know the year, sorry.

 

[JasonJ]

Re: Still losing power

So I can assume your fuel tank vent is clear, and your fuel pumps are up to snuff?

Maybe one or more of the coils are starting to break down, that can have similar effects like you describe. I don't know the year of your motor, but I assume it is distributorless with multiple coils?

 

[VikingRSA]

Re: Still losing power

Fuel tank vent is clear and fuel pump and diaphragm is replaced. Is there anyway to check whether the coils or trigger is on its way out?

 

[JUSTINTIME]

Re: Still losing power

yep u can test those items
u need a manual

 

[Laddies]

Re: Still losing power

It sounds like you are losing spark on one cyl, could be a coil, diode switch in one of the switch boxes or the bias wire between the boxes. The system will need to be checked in the water with a induction meter or a DVA meter as it acts up, I belive the heat generated by the sysem or even the engine it's self is why it only acts up at speed, that makes it one of the hardest problems to find. I had 1 engine that with the cowl off would not act up, so we had to use a induction meter with the cowl on and when we found wich cyl was the problem, repaced the coil, that did not fix it so we changed the switch box and that did. Good luck---Bob

 

[VikingRSA]

Re: Still losing power

Hope all you guys had a fun and merry Xmas! all the best for the new yearo

where would i be able to find a proper workshop manual with all the wiring diagrams and proper instructions and giving more info about the stator, trigger, CDI ect. the one i have by Clymer is not really a proper workshop manual. it's good but it does not cover the trigger and stator really in detail. any help??

 

[Laddies]

Re: Still losing power

You could get information you need out of a merc manual or I think you can download a electronics manual from CDI they are the best in the business, or if you just want the CD specs, we can help

 

[steplift20]

Re: Still losing power

did you change the fuel line and did you put the right size diameter on to small and you will have the problem your describing