87 Black max bogging on take off

[nat85501]

1987 150 Black Max XR-2 I just got the boat when I did a test drive it ran 54 MPH with good take off. Now it takes me a few hundred yards or a few miles just depending on how it feels to get on plain. Then on occasion while on plain it will bog down for a few minutes then pick back up. There is no miss-firing it runs smooth. Also the guy I got it from took the oil-injection off so I have to mix my oil in the fuel I mix Quicksilver premium plus at 50:1 straight into the fuel. Also I can?t keep the fuel bulb full I pump it up several time and once it get full it goes soft again while running or sitting. I replaced the fuel line from the tan to the male connector into the engine bulb and all. I took it to the shop the guy changed the stator and voltage reg I have changed the plugs. I have lost take off power and about 5 miles on the top end I have no idea this is my first boat thanks for any help really it would mean a lot. The serial # is 08210338. Could it be the fuel pumps.

 

[ClassyGlassy]

Re: 87 Black max bogging on take off

has it changed altitude since the test run? meaning, are you running it at a different lake at a different altitude then the test run? That would mean you have a carb air/fuel mixture issue or jet size issue.

it could also need a fuel filter change, the fuel pump rebuilt, vent on your gas tank cleaned/opened.

What kind of fuel tank does it have? I've also heard of different grades of fuel causing issues as well. Try and find out what grade of fuel the Previous Owner used.

 

[nat85501]

Re: 87 Black max bogging on take off

Test run done at same elevation. New fuel filter. Was thinking it could be the pump never thought it could be the vent. I have thought about it being the pickup tube or something in the screen. I have a fiberglass tank. I have run several types of fuel grade all leading to the same result.

 

[bowhunter58]

Re: 87 Black max bogging on take off

i had same problem with my 87 and believe it or not it was the primer bulb it wasnt holding pressure in check valves

 

[nat85501]

Re: 87 Black max bogging on take off

i had same problem with my 87 and believe it or not it was the primer bulb it wasnt holding pressure in check valves

I am very new to working on my boat what check valves are you talking the ones i am thinking of are were the male and female conectors were the fule line plugs into the motor that is the only part i can thinkof.

 

[Doug57]

Re: 87 Black max bogging on take off

The primer bubble has a check built in it that allows the fuel to flow in only one direction.

 

[santuitman01]

Re: 87 Black max bogging on take off

If you can borrow a portable 6 gallon tank with hose and plug that right into your outboard that might help eliminate the tank vent / fuel bulb question.

 

[Doug57]

Re: 87 Black max bogging on take off

I have an 84 150. Been down this road, my problem ended up be the stabilization module. This module controls timing and can be done away with. You can run a search on how to do this. It could also be you are getting ready to loose a switch box. Continue checking the fuel system for a problem and toss the stabilization module. Go to the auto parts and pick up a spark tester for a couple of bucks and check for strong constant fire on each plug.

Good Luck

 

[nat85501]

Re: 87 Black max bogging on take off

has it changed altitude since the test run? meaning, are you running it at a different lake at a different altitude then the test run? That would mean you have a carb air/fuel mixture issue or jet size issue.

it could also need a fuel filter change, the fuel pump rebuilt, vent on your gas tank cleaned/opened.

What kind of fuel tank does it have? I've also heard of different grades of fuel causing issues as well. Try and find out what grade of fuel the Previous Owner used.

Test run done at same elevation. New fuel filter. Was thinking it could be the pump never thought it could be the vent. I have thought about it being the pickup tube or something in the screen. I have a fiberglass tank. I have run several types of fuel grade all leading to the same result.

 

[nat85501]

Re: 87 Black max bogging on take off

If you can borrow a portable 6 gallon tank with hose and plug that right into your outboard that might help eliminate the tank vent / fuel bulb question.

I will try that this weekend thanks for the info.

 

[bowhunter58]

Re: 87 Black max bogging on take off

the check valve i was refering to is right in the primer bulb itself. mine would do same thing run and ball would get soft

 

[nat85501]

Re: 87 Black max bogging on take off

the check valve i was refering to is right in the primer bulb itself. mine would do same thing run and ball would get soft

I do have a brand new primer ball but maybe it is bad you never knwo i will change it anyways just to see if it has the same effect.