150 mercury black max fuel problem

[bassfisher21]

Hi. I have a 1990's vintage 150 mercury black max on my bass boat. My problem is when i take off or am on plane the motor starts to die the fuel ball goes soft ive checked all my fuel lines on the boat and rebuilt the fuel pump but still cant seam to get it to stay out on plane. The motor starts easy runs great at dock and idle and never has a problem on the muffs but when i go to pick the boat out on plane she dies. ive had my dad sit back and pump the fuel ball and it runs fine and picks out fast like it shopuld but without someone back there it just wont stay running. I did buy this motor with no fuel lines and tried to look at other motors to see how to put them back on but on my engine someone bypassed the oil injection so cant be sure i did it rite. Ive had this motor out cents though and it ran great till recent. The motor has geat compression from 125 to 120 on all 6. Any ideas whats wrong?

 

[CharlieB]

Re: 150 mercury black max fuel problem

Fuel restriction or air leak BEFORE the primer bulb or anywhere before the fuel pump.

Either will only allow the fuel pump to flow a limited amount of fuel, no where near enough to make much power.

Check everything from physically pulling the fuel tank dip tube to check for crud or cracks to a poor hose seal at any fitting.

 

[bassfisher21]

Re: 150 mercury black max fuel problem

I am now thinking a whole new motor i want a 4 stroke that is dependible speed is not a huge concern but would be nice just need a motor that can hold up for years of long rides with good economy. i have three dealers close to me honda,yamaha and mercury not sure witch i should choose any input? also im going with a 225 20'' shaft motor in any of these brands

 

[CharlieB]

Re: 150 mercury black max fuel problem

Economy and outboard are two words that do not even belong in the same sentence.

HP equals fuel flow, roughly 10% of the rated HP in gallons of fuel per hour. It doesn't make hardly any difference if it is a two stroke or 4 stoke, inboard or outboard, it takes fuel to make power.

If you have a fueling problem and simply swap to a newer, more expensive motor without solving and curing the fueling problem, you could burn down a new expensive motor.

That Merc has been around a long time, with a reasonable amount of care it will last a goodly long while yet, there are a great many would LOVE to have that motor.

 

[1nebel0]

Re: 150 mercury black max fuel problem

Put me on the list for the motor.. I have more motors in storage then I wish to admit to and yours is my favorite in the 200h.p platform...I have a 4 stroke also and if you think you got problems now wait till you pay for the cost of the 4 stroke.....the loss of the wonderful power a two stroke produces and lastly the fact that many people have problems with their 4 strokes making oil i.e. with fuel getting by the rings or the oil running so cold that you end of with a ton of water in the oil acting as if you have head gasket problem...Google 4 stroke outboards making oil and be prepared to read many posts....I do all my own work and I am not a merchanic...That is on the two strokes...need a computer program to do the 4 stroke on my pontoon boat...Yes they are quiet.....Bottom line fix your simple problem and enjoy that great motor.

 

[Maxz695]

Re: 150 mercury black max fuel problem

yep yep

 

[carholme]

Re: 150 mercury black max fuel problem

If someone is pumping the bulb and everything is working fine, then you still have a problem in your fuel pump system. Pumping the bulb makes you the fuel pump, so it is air, check valves or your pump rebuild was not done correctly.

Gerry

 

[bassfisher21]

Re: 150 mercury black max fuel problem

went with a new honda bf200 so if anyone is interested leave a reasonable offer