Motor Woes

[jrou111]

Originally Posted by macojoe

I just turned my laptop side ways!! But were was the sound?

http://www.youtube.com/watch?v=YJbPNt4kaHs

[phatdaddy]

i would be leaning toward going through the carbs. if it starts cold without using the choke, that is different. most mercs i have had are a little cold natured, but when warmed up are easier to start.
there are a lot of sharper mechanical minds on this site than mine, maybe they will come along today and offer some more specific directions.

[jrou111]

Originally Posted by phatdaddy

i would be leaning toward going through the carbs. if it starts cold without using the choke, that is different. most mercs i have had are a little cold natured, but when warmed up are easier to start.
there are a lot of sharper mechanical minds on this site than mine, maybe they will come along today and offer some more specific directions.

I'm thinking it's carbs, specifically the floats allowing the bowls to overflow and flood the motor.

BTW, the engine only fires up with no choke AFTER it's shutdown on me (which is why I think it's flooding)

Does anyone know how much $$$ I'm going to have to pay a mechanic to rebuild the carbs? I see the kits are around $25 x 3 carbs. I don't mind paying ~$200, but if it's more then I'll have to do it myself and pay someone to sync them. It'd take alot longer that way cause I'm lazy.

[bradford]

Think you're right on the carbs brotha.

[bigshrimpin]

Carbs are cake to rebuild especially on the older wh- carbs. If you're pumping the bulb and fuel is pour out the front of the carbs . . . the needles aren't seating (either from the needles being old or the floats not being adjusted properly). Get the kits and rebuild the carbs!! Also you might want to look into the low compression in that cylinder. You probably have a stuck ring . . . you might try decarbing (using power tune) the motor . . . spend a little extra time on that cylinder. If compression doesn't come back . . . I would pull that head and check the cylinder wall for scoring.

[Steplift 72']

Originally Posted by bigshrimpin

Carbs are cake to rebuild especially on the older wh- carbs. If you're pumping the bulb and fuel is pour out the front of the carbs . . . the needles aren't seating (either from the needles being old or the floats not being adjusted properly). Get the kits and rebuild the carbs!! Also you might want to look into the low compression in that cylinder. You probably have a stuck ring . . . you might try decarbing (using power tune) the motor . . . spend a little extra time on that cylinder. If compression doesn't come back . . . I would pull that head and check the cylinder wall for scoring.

I agree that 20 psi lower on one cylinder is bad. I had a few psi differential on a V4 looper that caused the motor to run really weak. The old Mercury "Boathouse Bulletin" says a Merc 150 should push a V20 to 46 mph with a light load and about 42+ with 4 passengers and full fuel. If you're running 42 mph, have you lost any RPM? I had less compression loss than that on one cylinder of a 6 cylinder Merc and it wouldn't crank cold without starting fluid! If you can find someone with a borescope you may be able to get a look at the cylinder walls without pulling the head.