84 Merc 115 tower of power - BOG on hole shot

Titan99

Seaman Apprentice
Joined
Nov 13, 2009
Messages
30
Greetings all.
Acquired this boat/motor over the winter and restored the boat.

Took the motor out for a couple of test runs and the first couple of trips it ran great and popped right out of the hole and ran great at WOT (5200 RMP)

However, now it seems to have developed a hickup.

It starts and idel's no problem, nice and smooth with no issue.
When you hammer it down for the start it bogs and dies like it's either flooding or not getting enough fuel. It seems to do this about 60% of the time, (IE it's intermittant issue)
if you bring the speed up super slow is will eventually kick in and pop out of the hole.

I've run 2 tanks of gas with one 1liter of sea foam in each tank.
I'm running premium marine gas mixed 50-1

compression is good on all cylinders (all within 5-10lbs and all around 110lbs) and the plugs look fine (may replace them as a matter of course)

It doesn't appear that it's misfiring at all.

thoughts on what I should do now?
I do have carb kits on order.
Should I rebuild the fuel pump?

Thanks in advance.
 

arsenalpsu

Petty Officer 1st Class
Joined
Dec 1, 2008
Messages
290
Re: 84 Merc 115 tower of power - BOG on hole shot

This is a classic symptom of lean running, I'd do a "link and sync" or just back each idle jet out 1/8 turn and try a hole shot. If it doesn't work keep backing them out 1/8 turn until you can.
 
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