1988 Mercury 150 hp xr4 blackmax

[jackofalltrades]

Re: 1988 Mercury 150 hp xr4 blackmax

Hey guys got the pdf. file great work by all responsible, their is so many of you helping me with this problem I'm overwhelmed with your interest and knowledge. What a great place for wealth of knowledge and willingness to share with others. My hats off to you guys. thank you very much.

 

[CharlieB]

Re: 1988 Mercury 150 hp xr4 blackmax

150's and larger motors, many owners prefer to use ONLY the Merc primer bulbs. One reason is part of the problem you are having, only one check valve, poorly seating the fuel drains back before starting, and two, total amount of fuel flow thru the bulb. Better valves in the Merc primer less restriction to the fuel pump while running, more fuel flow to the motor.

Poor sealing valves in the fuel pump when combined with that cheaper primer bulb will also allow fuel to siphon back to the tank.

Double check the fuel pump valves. While the pump is apart, lay the pump body on a piece of sandpaper on a very flat surface, like glass. Rub the body back and forth a couple of times then look to see if the whole surface is evenly cleaned, especially the valve contact areas. If not even, rub in figure 8's and recheck, stop as soon as the valve areas are cleaned.

 

[jackofalltrades]

Re: 1988 Mercury 150 hp xr4 blackmax

Thanks CharlieB just installed new bulb from mercury dealer, can see the difference now. My fuel pump kit will be in this week can't wait to change out and do what u said. I have worked on and rebuilt automobile engines since I was old enough to hold a wrench, but this outboard engine is a whole different program. Worked on a few but not to this degree. Might should have took it to a outboard mechanic, but I would not have learn a whole lot about my engine. Comes in handy when on the water and something goes wrong. This may be crazy but bringing this engine back to life is part of the fun to me. Thanks again

 

[jackofalltrades]

Re: 1988 Mercury 150 hp xr4 blackmax

Good morning, I rebuilt fuel pump last night and pumped up the bulb and you can see the fuel bleeding off in the clear filter. Are the check valves in the fuel pump the only valve that retains the fuel from bleeding off. Also the kit I received only had 2 plastic round flat valves with plastic retainers that snap in. The kit I got about a months ago had 2 of these valves and 2 rubber valves that I put under the plastic ones the first time. Are these fuel pumps suppose to have 2 pieces on each valve or just one. Need to know I might be ordering the wrong kit. please help

 

[Faztbullet]

Re: 1988 Mercury 150 hp xr4 blackmax

The filter will not stay full due to seepage thru bulb. Check valves in bulb only completely closed under pressure. You should be good to go, also filter will not stay full when running either

 

[jackofalltrades]

Re: 1988 Mercury 150 hp xr4 blackmax

Wanted to let you guys know I took the boat out today and something strange happened. After getting bleed lines in correct position and rebuilding the fuel pump the boat ran a little better so I hit the enricher and it took off like a shot run beautifully until I slowed down and nailed the throttle again same thing happen again, so I hit the enricher again and it took off like a shot again, Runs beautifully. Its got to be something in carbs when you first nail the throttle. Only picks up when the enricher is used and when I said it picks up I mean it picks up and takes off like a shot. Any ideas are welcome thanks to all.

 

[CharlieB]

Re: 1988 Mercury 150 hp xr4 blackmax

Bogging on load/acceleration is most often caused by a LACK of fuel thru the idle circuit. The small idle passages and air bleeds can sometimes literally be crusted with mineral accumulation, restricting fuel/air flow necessary for crisp acceleration. The main is a very large passage and easily cleaned, once you manage to get the motor sped up it runs fine at 1/2 throttle or more. But just off idle and trying to accelerate it bogs, it is most often dirty idle passages.

WalMart Super Tech Carb cleaner is once of the best (and cheapest) carb cleaners available. Use the little tube and blow it well thru every passage while looking to see where it comes out, you want to see a full stream coming out. WEAR SAFETY GOGGLES or something, this stuff will fell like you are going blind if it gets into your eyes. Sometimes the mineral is so well attached I pull a wire from a wire brush and use it to 'probe' a passage to dislodge stuck gunk.

Ensure all floats exactly the height prescribed for your motor and carbs.

Link and synch the carb linkage, throttle cam, and timing , it does make a big difference.

Do you have a factory service manual? Not one of the aftermarkets, they leave out too much important details.

 

[wired247]

Re: 1988 Mercury 150 hp xr4 blackmax

Try opening up the idle mixture screws a bit.

 

[Dukedog]

Re: 1988 Mercury 150 hp xr4 blackmax

Try opening up the idle mixture screws a bit.

:facepalm:

WH's......Not any.

 

[wired247]

Re: 1988 Mercury 150 hp xr4 blackmax

:facepalm:

WH's......Not any.

Having a bad day dukedog?

 

[Dukedog]

Re: 1988 Mercury 150 hp xr4 blackmax

so-so. Actually got ta watch tha Blue Angels practice taday.

Did ya forget ta put that in ya book last time it came up? Your gettin' older so ya might wanna "practice" writin' stuff down. I go through 5 ta 6 pads of sticky notes a day now.......

 

[wired247]

Re: 1988 Mercury 150 hp xr4 blackmax

All I ever play with are WMH's and WMV's. Keep forgetting about those damn WH's and their goofy idle circuits. Old ladies off in Europe spending my annual bonus so its beer, Top Ramen and dirty underwear for me for the next two weeks. I also get the joy of being able to receive UPS packages with no oversight. Life is good. She doesnt know it but the bonus Gods were particularly friendly this year and she's only off spending half of it.:laugh: Heres a nifty cowl set I got in the mail today...

 

[Faztbullet]

Re: 1988 Mercury 150 hp xr4 blackmax

WH's......Not any.

Beat me to it DDog............

 

[Dukedog]

Re: 1988 Mercury 150 hp xr4 blackmax

He knows that. Jus hada fart!!!

Cowl looks good...........

 

[jackofalltrades]

Re: 1988 Mercury 150 hp xr4 blackmax

thank you dukedog, I got the carbs cleaned and rebuilt. Took It to the lake and the same thing is happening. Just bogs around until u hit the enricher. Going to anti foul plugs and try that. Will try ur suggestions before trying again. Haven't touched link synch, throttle cam, and timing yet so will try that to thanks again. You guys have been great keep it coming ha ha.

 

[Dukedog]

Re: 1988 Mercury 150 hp xr4 blackmax

If it comes ta life when ya hit tha enrichner ya still gotta fuel problem. Most likely carbs or pump but definitely a delivery problem somewhere...........Keep tha bu8h's in it. Anti-fowl is snake oil...........

 

[jackofalltrades]

Re: 1988 Mercury 150 hp xr4 blackmax

Ok got 6 bu8h's ordered should be in today. I did a pressure check on the fuel pump and got 5-7 psi which should be sufficient. Also I am confused about anti-foul snake oil. I thought the anti foul was the slick bottom plugs with no tips. Which is what I ordered in the bu8h nkg plugs. Please correct me if I'm wrong.

 

[Dukedog]

Re: 1988 Mercury 150 hp xr4 blackmax

Just plug design. Not anti fowl. But it is a little harder ta fowl 'em.....

 

[wired247]

Re: 1988 Mercury 150 hp xr4 blackmax

Theyre also just about impossible to read.

 

[jackofalltrades]

Re: 1988 Mercury 150 hp xr4 blackmax

Yea your right about the reading, ok I got it thanks.