Can't Get Motor Started

[jr45]

I bought a boat at the end of March.  It has a 78 Mercury BlackMax 175 HP motor on it with hot foot.  I took the boat out a few times this spring, then baseball and softball season happened and its been sitting.  I am have a really hard time getting this thing to start.  I also had a hard time getting it to start when I took it out in the spring.  It was taking 15-20 minutes to get it to start then.  Once it starts it runs awesome and I never have problems starting it again.  Is there a trick to getting these things started.  I have pumped the ball up, I have choked it, I've tried getting on the throttle.  I don't know what I did back in the spring to get it started, it was never the same.  The guy I bought from didn't have it but a few weeks, so he isn't much help.  I really want to go fishing, but I want to be able to get this thing started.  Thanks for the help!  Carbs, and everything was replaced on motor this winter before I got it.

[lmoore]

I'd recommend getting a compression test run. Poor compression will make it almost impossible to start, and a test can be done for little to nothing.

Other than that, are you getting spark?

[Ski213]

+1 on compression check. Not as desirable as a leak down test but a good starting point to get an idea of the outboard's general mechanical condition. Beyond that you get into fuel, fire, and air. Which can be real simple or real complicated problem.

Way2slow would be the one to attack this. He can break these things down like a shotgun.

[Maxximus Redneckus]

Fresh gas and oil and what others have said

[Karma]

Same situation you are in, just bought a used boat earlier this spring and was having starting issues.

 

My neighbor runs a small engine repair shop and he came over to help me get it going this past weekend. I had great compression but 1 cylinder was not firing due to a loose cable running to the coil pack from the power pack. Fixed that.

 

Then we took the fuel lines and carbs off and noticed some build up. The previous owner had been using fuel with ethanol in it. A green/yellow wax had build up inside the fuel lines and in the fuel intakes on the carbs. We had to clean that out on the carbs and I just went ahead and replaced the fuel pump and fuel hoses leading from the pump to the carbs.

 

Fires up great now.

[Way2slow]

Check the compression

Check the battery, make sure the voltage is not dropping below about 11 volts when cranking.

Mix up some premixed gas and put it in a spray bottle, Pull the cover off the carbs, open the butterflies in carbs, give each carb a good spray of gas and then try starting it. If it starts easy then check your choke/priming system. DO NOT SPRAY STARTING FLUID IN IT! If that makes it harder to start, it may be flooding.

[jr45]

Compression test was done right before I bought it 4 months ago it was all good, but I guess that could have changed.  It has only had premium non ethanol gas in it.  I think maybe I am getting it flooded before starting it??  Maybe choking it too much??  It doesn't have the push in key, they guy who owned it make the choke a toggle switch thing on the dash.  I can here it click on the motor when I choke it.  I've been pumping the bulb until its really hard, turning key on, choking for around 20 seconds then trying to start.  I jacked with it for 30 minutes last night and only got it to kick one time.

[Way2slow]

Glad you have it figured out.

[Ski213]

Have you tried to prime it for a shorter period or not at all? If so did it make any difference?

[WIGuide]

Are you choking it while cranking it? If not, it's not doing anything to help the engine start. If you're wise though, you'll take the time to take way2slow's advice. The guy is like a master mechanic so don't be an idiot and disregard his info.