seems to miss under load

[FAZA]

75 Hp 1976 Evinrude on 16ft f/glass boat. Idles beautiful. Compression, Top 130lb, Mid 140, bottom 140. throttle up seems to miss, no power. Good spark, carbies cleaned. Friend has suggested that top carb on these motors tends to starve for fuel. Suggested changing the fuel bowl with main fuel intake from middle carb to top to ensure fuel in top and make use of gravity to feed the other two. What do you think? Has that been done before or should I be looking for something else?<br />Thanks.

 

[Dhadley]

Re: seems to miss under load

Lets hope your fuel pump is strong enough to overcome a bit of gravity!<br /><br />What spark plugs are you using? Fresh fuel? Coils and wires good?

 

[Cricket Too]

Re: seems to miss under load

Never heard of the top carb running lean due to fuel pump pressure, but have heard that the middle carbs tend to run lean on those motors. Even though you say those carbs are clean you should make sure that top one is adjusted properly before that 10 psi. turns into alot more. Good Luck.

 

[FAZA]

Re: seems to miss under load

Thanks, I have discovered hairline cracks on to of the coils, cylinder head side. I'll get hold of some more and get back to you.<br /><br />Thanks again, FAZA

 

[red10]

Re: seems to miss under load

i had the same problem with evinrude 70 ended up being a coil with a hairline crack, idled great but no power on throttle up, hope this helps