blackmax bogging

stratos275xl

Seaman Apprentice
Joined
Mar 24, 2013
Messages
41
I have a 95 blackmax 150 carburated and Im having problems with motor after having a shop change my powerhead over to another mid section and lower.ran great first time out.then the second trip i made a 10 min run at 5 to 5500 ran nice.stoped to fish fired it up and took back off ran great for about 30 seconds just lost power all at once and would just bog and miss .all i could do was idle back about 8 miles..came home checked compression was 120 on 4 of them 115 on other 2.changed plugs was getting fire and ran good outa the water on muffs.did have bottom cylinder not firing as good at idle as the others .took back out today and seemed fine idling but soon as it hit about 4000 on holeshot it choked out and fouled plugs again and it wouldnt get above 1800 rpm.now when this happens it still starts good but has miss tho obviously because of plugs.but i dunno where to start honestly. Some people say its gota.be stator others say maybe carbs. Any advice appreciated.thanks
 

Bosunsmate

Admiral
Joined
Apr 7, 2012
Messages
6,135
Re: blackmax bogging

check your wires on the spark advance arent shorting when you move the timing, heat can overtime melt them and short them.
Possible powerpack im thinking too.
Also change your bottom coil and see if that moves the poor spark at idle on bottom cylinder
 

stratos275xl

Seaman Apprentice
Joined
Mar 24, 2013
Messages
41
Re: blackmax bogging

I just done a quick look over at the lake when i got
It trailerd and did not see any broke wires or
Vaccum lines but i know obviously a quick check wont
Tell me anything unless was just real noticable.I had a mechanic
Check the firing with some thing he had that pluged
Into 3 wires at a time.he said all 6 were firing but the bottom
Left cylinder when u pulled wire while running didnt
Change much.can a carb problem cause just one
Cylinder to not fire?i thought each carb controlled 2 cylinders but i
May be wrong.
 

stratos275xl

Seaman Apprentice
Joined
Mar 24, 2013
Messages
41
Re: blackmax bogging

I will check everything you mentiond after work today tho
.i was just curious bout carb doing that. I did find
An 88 blackmax for 350$ thats blowed just for parts
But wasnt sure if the electronics would be same as my 95.
 

CharlieB

Vice Admiral
Joined
Apr 10, 2007
Messages
5,617
Re: blackmax bogging

Each carb is two separate carbs sharing a common body and throttle shaft. Separate floats, needle/seats, jets.

It may be possible that hte high speed windings of the stator are failing.

Since there is NO RETURN on electrical parts you never want to assume anything and start spending money. (Unless it is for a tool).

Get the free Igntion Guide from CDI Electronics.

CDI Electronics Practical Outboard Ignition Troubleshooting

With a DVA Meter or a DVA Adaptor for any Volt/Ohm Meter you can check the triggers and stator and KNOW what is good/bad.
 

stratos275xl

Seaman Apprentice
Joined
Mar 24, 2013
Messages
41
Re: blackmax bogging

I just thot mite be good to have parts motor laying
Around but your rite especially since im already alot
Into now.i appreciate info on the carbs thats good to know.i will
Break out the ohm meter after finding out what to check
And what resistence im supposed to have.im pretty decent at that
From exp of wiring gremlins on 4 wheelers n bikes all the time.thanks fot help guys ill report
Back soon as i figure it all out.
 
Top