Full throttle issue

Starboardlean

Seaman
Joined
Feb 15, 2016
Messages
73
1978 85 HP Evinrude. Cleaned and Rebuilt carbs. New fuel pump, fuel lines with filter, 4 spark plugs,4 coils,1 power pack, water pump, About 105psi each cylinder. Strong spark. 50:1 pure gas/oil. Last time out( last weekend) it had a "hiccup"(bog down) at close to WOT. Ran fine when backed of a little. Kinda played around to repeat "hiccup". Sure enough more than a few seconds near WOT and it happened again. Tried to "jump" it on plane versus the usual easing into it. Hiccup and it couldn't plane. Repeat and this time ease it on plane no trouble. Momma then took control and I worked the bulb, hiccup still! Cruise at 3/4throttle all day fine....New Ql77jc4 installed Friday..Today we go to the lake. Starts easy enough....whatever happened near WOT has now happened to any attempt to exceed the no wake speed. Push the throttle forward, just a bog, and a occasional blip of power that quickly dissipates. Stalls. Restarts fine. Occasional bog now just one constant bog. But she idled back to dock fine. Get home removed air intake cover and have small puddle,maybe a thimble full of fuel in the cover,fuel obviously oozing out of top carb. Normal? Ideas or pointers??
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
I'd take a look at the carbs again, plus check for spark when it's acting up.
 

interalian

Commander
Joined
Jul 23, 2009
Messages
2,105
Odd that it got worse with new plugs. What spark plug gap did you use for the ones that went in Friday? Should be 0.030"
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Agree. May not be running on all 4 cyls. Check the spark when under load.
 

interalian

Commander
Joined
Jul 23, 2009
Messages
2,105
Having gone through dropping just one cylinder, I was surprised how badly it runs on just 3.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,638
When you were 'working the bulb' was the bulb refilling with fuel or was it staying collapsed? To me it sounds like a fuel supply issue. The fuel requirements between 3/4 and full throttle is quite surprising.
 

Starboardlean

Seaman
Joined
Feb 15, 2016
Messages
73
The bulb felt firm,not collapsed. I read the recent post about carb leaking...I guess the small amount i saw is normal,I had been wondering what the small hose on the bottomof intake was for. How do I (safely) check a cylinder losing spark under load? It is does unpredictably jump hard....this one I might have to leave to a mechanic. I am sure they are all backed up for weeks. It is frustrating to tinker cause the lake is 30 miles away. Got a nice river close, but any less than healthy motor will be down stream....
 
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