Evinrude 9.9 problems

Im new to outboards and am having a problems with my 1996 evinrude 9.9. I just picked up a new boat with it on and at WOT it bogs down and barely builds rpm. when you back off the throttle it starts to pick up a little speed but still maxes out my 15ft sea nymph at 8mph, I knew something was wrong because my friends mercury 9.9 with the 15hp conversion will push his 17ft at 14.5mph. So far I have cleaned the carb (15hp carb), checked and cleaned the fuel pump, replaced fuel fittings, done a link and sync, changed spark plugs, and a few other small things like fresh gas/ sea foam etc... the motor also seems to have a hard time idling even after setting the adjustment to its best running setting. once in the water it likes to stall out when put into gear from the added resistance of the water. The motor also seems to surge, it is most noticeable when im only at about 1/4 throttle.

Ive done some tests while at WOT like pumping the primer bulb and pushing the choke on with no change at all. i have also pulled off each spark plug wire while it was idling at home to make sure I didn't have a dead cylinder, everything checked out ok so far. Im pretty stumped now so any help is greatly appreciated. i just want to get out and enjoy this thing without worrying about getting stranded on the lake.

Here is a video, you can here the rpms drop when I go WOT then rise again as I back it off to about 3/4.

My advise is always the same.----Check compression and report your results.----Test for strong spark on both leads , must jump a gap of 7/16" or better.-Did the dealer install the correct prop for the boat / load ???

Haven't been able to check compression because I have the carb removed, ill check spark once I get everything back together since I am waiting on some new parts for the carb. the prop on it is a 9-1/2x10. Also, I took this picture of what I think is called the emulsion tube? it looks a little dinged up and I wasn't sure if it was supposed to be angled like that.

One other thing that has me confused is the model number, mine is E10RELEDE, I cant seem to find it listed anywhere.

Carburetor is not needed to do a compression test.

Ok, ill do one tonight, anytime i ever did one on a quad i was told to do it at WOT.

With a 2 stroke WOT is not needed.----When the carburetor is off it is in fact at WOT !!

You are right about the WOT word. A closed main throttle valve in the carburator will create a very high vacuum condition which can slow down the cranking speed on tired batteries and or weak starters. A stick or another person works fine. Most people have no idea when a starter is spinning fast / correctly

A 15 hp carb can be too much carburator for a 9.9 hp old virgin. Go to http://www.leeroysramblings.com about losing power if all the factory parts are not used when trying to go from 9.9 to 15 hp.

My 1995 electric is a E10RELEOE

could your D be a O ?

On a 2 stroke the exhaust ports are wide open and compression does not start till they are closed by the piston.---Carburetor absolutely does not need to be at WOT !!!

The correct web address is www.leeroysramblings.com

Just checked compression and after about 3 very quick cranks of the starter I got 90 and 92, so that seems fine.

Just did a spark gap test and it jumped the 7/16 no problem. Anyone have any other ideas?

A 15 hp carb can be too much carburator for a 9.9 hp old virgin. Go to http://www.leeroysramblings.com about losing power if all the factory parts are not used when trying to go from 9.9 to 15 hp.

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I agree that the 15 hp carb is very likely the problem. I read galamb's recent explanation in another post about mixing/matching engine parts to increase HP and it fits your problem. The exhaust system is too small for the increased intake air/fuel volume.

Ok, I might just pick up a used 9.9 carb to see if that fixes the problem. Is there any difference besides the carb on a 1996 9.9 and 15? Ive tried searching, but most sites have conflicting answers.

I would guess not. As people found out that the engines are a detuned 15 hp motor using a reduced carburator set up. They jumped on the obvious.

Lee Roy had a specific section on his site detailing all the parts need to convert to a 15 hp with a 9.9 case on the covers for 10 hp limited places.

In NJ ALL park rangers could easily tell just by sound / speeding & then looking at the prop & the load of the boat.

These newer 9.9 / 15 HP motors share many of the same parts .--Difference is in the carburetion / jetting.----Same displacement so the same amount of air is processed as well.-----They do run much nicer than the older versions due to different intake ports and a heavier flywheel !

I never can get rid of that noticable kick when in neutral or minimum trolling speed.

Thanks for explaning the reason.

Thanks for all the help, but ive got one more question before I break down and buy a new carb, then possible a new motor if it still isn't fixed instead of throwing more money at it. I noticed exhaust coming up in front of the cowling while on muffs and also while on the lake cruising around. could an exhaust leak cause these symptoms or is this normal?

Figured id give an update on the situation. Did some fine tuning and am relatively happy with it now. I still get a bog at wot after the butterfly is open completely and the timing continues to advance. Ive gone through everything i possibly could and couldn't find the problem so I'm just going to live with it. I took my girlfriend (usually have a heavier person on board, extra 100lbs) out on the boat last weekend and was able to get 14mph which is great, but as soon as I filled the live well up, we couldn't get up on plane and got a max of 8-9 mpg. I bought a hydrofoil and am going to take some weight out of the boat so hopefully it will run like this at all times. below is a video from last weekend compared to my first one.