1988 200hp merc runnimg rich need some help please

[bassangler1027]

I have a 1988 200hp merc and it is running rich . and it is loading up when takeing off but then cleaning out and running great WOT ( 5400 rpms) here is what i have done to try and correct the problem

first replaced plugs and wires , cleaned carbs and new gaskits , when cleaning there were little pick up tubes goes to bowl to mixing chamber that were pluged up, rebult fuel pump and it got alot better but still loading up ( wet plugs) but not as bad

so today I checked timing ( by the manuel) and it is in time , LINKED and SYNC it is all good
checked stator, trigger and coils they all check good

checked compression ( 130-128 lbs on all six)

replaced fuel lines but not primer cause it gets hard when primeing but it is pointing down so check valve is staying foward not sure if i need to reposition it .

and also i did not check the floats adjustment and I was wondering if the are letting to much fuel in bowls if this would cause it to load up , I am thinking it would but just need some pointers thanks alot

also it has a 13 7\8 23 pitch prop but according to the prop guys thats right for this boat and weight 21 foot stratos 1990

 

[Maxz695]

Re: 1988 200hp merc runnimg rich need some help please

your flost level is very important it shuts the gas off when it reaches the point it needs to be at. If the level is over level then gas will pour into the carb and cause a flooding effect. Also if the needle and seats are not sealing properly then gas will continue to folw even if the float level is correct

 

[Faztbullet]

Re: 1988 200hp merc runnimg rich need some help please

Max has a point and check the recirculation valves as if plugged they will cause engine to do this...

 

[bassangler1027]

Re: 1988 200hp merc runnimg rich need some help please

Ok i removed all carbs and check floats and the repair Manual says to turn bowl upside down and bottom of floats need to be1/16 from edge of bowl. And so i readjusted them cause it seem to me that they were past the edge and after i adjust i made sure that seat sealed by blowing into them and it shuts the air off and before i did this i blow into them and air would move through with no restriction and know there is a little more restriction and the air is a little slower moving threw so i would assume this would apply with fuel moving through so maybe this will help. I am going to take to lake in morning and lake test. And is the recurculation valve that you have mention. Is that that little round thing with two vaccum lines coming out of the bottom going to carbs. And is so how do i check it.

 

[bassangler1027]

Re: 1988 200hp merc runnimg rich need some help please

Oh yeah i adjusted the floats to be dead even with edge of bowl. And if it gets better and don't load up as much well then i will know if i am on to something. Cause i don't want it to get to lean.

 

[Faztbullet]

Re: 1988 200hp merc runnimg rich need some help please

The recirculation valves have the bleed lines attached,they are the small little lines off intake to sides of block

 

[aussieflash]

Re: 1988 200hp merc runnimg rich need some help please

Oh yeah i adjusted the floats to be dead even with edge of bowl. And if it gets better and don't load up as much well then i will know if i am on to something. Cause i don't want it to get to lean.

Ok, you said 1/16(1.6mm)float overhang when bowl upside down which is spot on.......so why are you going level.It will probably run like a scalded cat...till she blows a cylinder due to running LEAN.
I would re adjust to spec if you want to keep motor

 

[CharlieB]

Re: 1988 200hp merc runnimg rich need some help please

................ the repair Manual says to turn bowl upside down and bottom of floats need to be1/16 from edge of bowl........................

So you adjusted the floats to be EVEN with the edge instead of 1/16 up from the edge.

Remember that the carb is upside down, adjusting the floats lower than prescribed in the manual results in the fuel level HIGHER than required and causes the fuel mixture to be RICH.

You will need to adjust the floats correctly, exactly as the manual prescribes.

 

[bassangler1027]

Re: 1988 200hp merc runnimg rich need some help please

I started boat this morning and noticed that it was blowing fuel out the bottom left carb so I inspected reeds and found a broke reed so I would think that this is the root of the problem so I bought a new set aswell as a new gaskit and installed and it does seem to run better at least in the driveway . and after running engine I pulled plugs and they are still wet but not as bad . and the book really don't say if it the bottom of float should hang 1/16 past the edge or bottom of float to the edge of bowl so i figured even would be a happy medium. but i am positive for sure that this reed being broken was the problem. but if anyone positively knows the correct adjustment on these floats please advise me. and i will correct tomorrow afternoon cause going to take to lake sunday. but it has these surface gap plugs in it and it is hard for me to judge . are they supposed to be wet are dry , cause the book says dry and powdery but then is shows a pic of a standard plug that need to be gaped. so please inform me of these so they can be corrected. thanks.

 

[Dukedog]

Re: 1988 200hp merc runnimg rich need some help please

go here..........

http://www.screamandfly.com/showthr...ght-on-WH-20-Carbs&highlight=float+adjustment

 

[bassangler1027]

Re: 1988 200hp merc runnimg rich need some help please

problem fixed reeds were the problem also readjusted floats to spec , thanks for the replys