mercury black max 200?????????

[IUSEN20]

i have a 23 ft proline walkaround cuddy 1984 with a 84 black max 200 on it with a 17 pitch prop.....boat i think weights about 4000lbs .....i had my wife and and 5 kids on board and cooler maybe a total of 1000 extra pounds .....boat would only do about 18 to 20 mph.....when u go WOT it goes to about 3400 rpm for about 45 sec. and then jumps up to 5100 rpm and stays there .....but the speed is way off i think....just does not feel like it has any power....new fuel filter, seperator and primer bowl. new plugs, and good compression all across the board 130psi.....any help would be great ......i am little mechanic smart so just looking for a place to start.....

 

[Faztbullet]

Re: mercury black max 200?????????

Your about 500 rpm low on rpm, how does it run with the weight out of it? What is max rpm with 1 person? What is speed with 1 person? You need to check ignition system as it may only be running on 5 cylinders and you need to turn that motor 5500 rpm.

 

[199675hpforce]

Re: mercury black max 200?????????

again lol fuel pump diaphram lately?

 

[IUSEN20]

Re: mercury black max 200?????????

it does about 25 to 27 mph but the rpms never go over 5100...it seems like it runs great but no power ....i thought this combo should run in the high 30s low 40s ....i will check the fuel pump and check cyl. with laser temp gun to see if they are all firing

 

[Maxz695]

Re: mercury black max 200?????????

Just a suggestion but the bushing in the prop might be getting worn out

 

[IUSEN20]

Re: mercury black max 200?????????

WILL THIS MAKE IT FEEL LIKE ITS SLIPPING ......BUT IF IT WERE SLIPPING WOULDN'T IT REV OUT AND NOT STAY AT 5100 ....WHEN YOU GO WOT IT GOES TO TO 3100 OR SO ....FOR LIKE 30 TO 45 SEC....THEN JUMPS TO 5100 AND STAY THERE BUT REALLY DOES NOT FEEL LIKE IT GAINS A LOT OF SPEED....I THINK AT BEST WITH JUST ME IN THE BOAT IT TOPS OUT AT LIKE 30MPH....JUST SEEMS LIKE IT SHOULD RUN IN THE 40s WITH A 200 MERC.......THANKS FOR ANY HELP ON THIS...

 

[j_martin]

Re: mercury black max 200?????????

Yes, usually it'll wind right out when the hub goes, and it'll get worse real fast till you are rowing.

How's your prop. It sounds like it's over propped to start with, and then cavitating to boot. It doesn't have to be bent up too much to do that. Too steep a ventilated prop might act like that even if in good shape. 5100 rpm is pretty low for normal WOT operation.