15hp Yamaha Starting Problems

[FreeBayliner4Us]

When I pulled my jon boat out of storage this spring I was pleased that the motor started on the second pull. It ran great on the first three outings. Then I rerouted the fuelline. I disconnected the fuel bulb so I could route the fuel line behind some support braces and reassembled it.

Now when I go to start it is usualy takes 10-15 pulls to get it to sputter to life. I figure I screwed something up when I disassembled the fuel line but I can't find anything wrong. To make things worse I feel I have lost a bit of power at full throttle.

Any help would be great!

Mike M.
Richmond, VA

 

[woody66912]

Re: 15hp Yamaha Starting Problems

MIKE if you rerouted the fuel line behind some braces with an opendend line you might have got crap in the line. when you reassbeled the line you you probly pushed that crap into the carb. pull carb down and clean don't forget to clean low speed .turn low speed screw in first count # of turns do this LIGHTLY good luck.

 

[FreeBayliner4Us]

Re: 15hp Yamaha Starting Problems

I made a point to cap the lines before routeing them for that reason. Try again!

Mike M.
Richmond, VA

 

[scottcmb]

Re: 15hp Yamaha Starting Problems

has the hose got a kink in it now since you re-routed it?...if not, sounds definatly like a fuel blockage and you will need to start at the tank and work all the way to the carbs to check for debrie somewhere.....also possibly murphies law could have donned you and the fuel pump gave up the ghost at the same time.....also check fuel tank breather

 

[FreeBayliner4Us]

Re: 15hp Yamaha Starting Problems

Checked, no kinks, tank and lines appear trash free. I have a feeling that I may have cracked the bellow some how. It just seems like it could be sucking air into the lines. Wouldn't this cause a lean condition? I had a hell of a time getting it started after the routing job. Now, it seems like each time it gets easier. I still feel like I am short on power thought.

Thanks!

 

[scottcmb]

Re: 15hp Yamaha Starting Problems

if there is a place along the fuel line from tank to pump that air can get into, the fuel pump finds it easier to draw air rather than fuel, and this will most curtainly cause a lean running condition and will result in engine damage in the end.
To determine an air leak, disconnect the fuel line at the carby and plug it up, unbolt the fuel pump from its mount but leave the fuel lines connected, then start squeezing the primer bulb to pressurize the the line with fuel, if the bulb ends up going hard after squeezing a few times and there are no fuel leaks from bulb to plugged end, no air is getting in from bulb to end of the line at the carby end. if the bulb stays squishy and hear a sifting noise and there is no fuel leaks i would then be paying close attension at the bulb and the line from bulb to tank for an air leak or a faulty priming bulb.

when you were encountering your problems with your engine whilst running was the primer bulb flattening? if it was there is an obstruction from bulb to tank! tank vent blocked maybe? etc etc.
the best advise i can really give you is start at the beginning of the fuel system, the tank and check everything that makes that do its job (vent and outlet) then check all hosing make sure they do there job, dissconnect the primer bulb and make sure it works the way it is suppose to ( a one way valve ) etc etc all the way to the carby.....when you are totally sure that the fuel supply is in top order...and you still have a problem then look at the carby for dirt.
Another thought.......how much extra fuel line did you install when you re-routed your line?....the more line you install the harder your fuel pump has to work!!
Hope all this helps you

 

[Yamajoe]

Re: 15hp Yamaha Starting Problems

I agree and if you fail to find the air leak problem from tank to pump, tear down the carb and clean. closely examine your connector to ensure these are sealing properly when connected at tank and motor ends.

 

[FreeBayliner4Us]

Re: 15hp Yamaha Starting Problems

Thanks Scott,

I have haven't had a chance tear into it yet. I think you are on the right path though. To answer your question, I didn't add any line just rerouted it.

I ran the boat last weekend and it started on the 2nd pull. After the first start it started the 1st pull everytime. I still think it has lost a little power though.

Thanks again!