2001 Johnson outboard, sudden surge of power at full throttle

[Sicrx69]

After locating an older post with the similar issue i wanted to post about my new issue. A new boat to me, the maiden voyage was running great then lost power at full throttle. When i throttle down and open it up again, it surges for half a second then loses power again. If I hit choke, it also surges after a few seconds then loses power again. I haven't checked yet but almost positive it's trash in fuel system, probably in carb. I am going check filter in the next few days and if I see evidence of trash. I am then gonna remove and clean carbs. The only thing that makes me think It could be something else is when i disengage prop and throttle up, it doesn't lose power or sputter but of course it's not under load. Hopefully it's a quick fix though.. Btw it's a 2000 Palm beach 161 with a 70 HP Johnson.
I located some numbers on the main body of engine if that helps as well. ACN 008 414 917.

While I have your attention, on a side note, after I replaced bilge pump and aerator, i noticed a similar hole on the starboard side near the Bilge pump drain hole. This hole i am referring to has a small screen on it and a use on other side near oil tank. I haven't had a chance to trace it to see what it is but thought someone might know of the top of their head. Its a 2000 Palm Beach 161 as well. Below is a picture of it with the Bilge pump drain hole on left and the mystery hole on the right. I know its not for my front live well because that aerator plumping in located on port side of the boat. I also have separate live well but is also located on port side of boat and don't think it has any sort of plumbing to it.

Thanks again everyone,
John

Ps will post as i make progress.

 

[Bosunsmate]

Might of being for another pump outlet if you have a double floor on that boat
The fuel lines past the filters can breakdown so you might not see any offending debris in the filter
You might want to check compression too

 

[Sicrx69]

Update,....I was able to fix the power issue, as I suspected it was trash in carb. I removed the air box and used sea foam spray throughout each carb while running it. I also removed and cleaned the fuel filter to which i located very small peices of trash. I then removed the carb bowls and also found trash in them. I cleaned it all and reinstalled. Luckily for me, the trash blew through and haven't had an issue since.

As for the mystery holes, well it's still a mystery. I do have several compartments but only one, front live well, has a drain and inlet hole. I think maybe it's a vent hole for fuel tank? Any guesses?
John

 

[Bosunsmate]

probably not a vent hole as itd get water in there.
If it was me, id blow my beekeeping smoker smoke down there and see where it came out (after all fuels removed) or put down a wire and scratch around and listen to where it is

 

[tblshur]

my freind has boat with similar port that is the pick up for rear livewell fresh water. hope this helps:joyous: