(UPDATE) 150 Merc top end Miss

[Hasbeen]

Posted a few weeks back with a problem with my Merc 150! Ran fine, then on way home it shuddered a little and the horn went off (double beep) Shut it down and after that it ran rough at WOT! Did compression check and found 120 all the way accross! After posts I did the following!<br /><br />1 New switch (The one the beeper attaches to) All new fuel lines, new bulb, new filters, new fuel pump, removed and cleaned carbs, new gaskets!<br /><br />Went out on the lake this after noon and ran perfect,Thought I had it whipped, (For about 30 Seconds) Then the beeper beeped twice so I shut it down! Started back up fine, beeper came on and off like it was suppose to but now running worse than It did before! Missing, bucking, no coughing, very uneven! <br /><br />What Now?? <br /><br />Hasbeen

 

[The Marine Doctor]

Re: (UPDATE) 150 Merc top end Miss

Is this an oil injected engine?<br /><br />TMD

 

[LubeDude]

Re: (UPDATE) 150 Merc top end Miss

Yes it is, but the system seems to be working properly!<br /><br />LubeDude

 

[Hasbeen]

Re: (UPDATE) 150 Merc top end Miss

I cant help but think someone must have an Idea about this!<br /><br />Other things done!<br /><br />New plugs, new fuel, (87 octane),de-carb,<br /><br />I did notice that it seemed to not be charging like it should this time! Could it be a voltage issue to the ignition? Why did it run great for 30 seconds, then went to crap??<br /><br />Hasbeen

 

[LubeDude]

Re: (UPDATE) 150 Merc top end Miss

Im going to keep bringing this to the top, as I really need help here!! I do not have the kind of money it will take to take this boat to the dealer! I have lots of knoledge and mechanical ability and plenty of time not to mention living on a lake to test it out!<br />Please see if you can help with this problem, any help will be greatly appriciated!<br /><br />LubeDude

 

[shelbydriver]

Re: (UPDATE) 150 Merc top end Miss

Just some ideas, do you have a manual? check the connections, check the coils with ohm meter? When it is running bad take off the spark plug wires one at a time and see if you are getting spark. I just got mine running after a long battle.

 

[bluebyyou]

Re: (UPDATE) 150 Merc top end Miss

Is motor running off of a metal gas tank? Have you always had a filter on it? Except for the horn going off it sounds like it could be junk in the carbs. How does it idle?

 

[gss036]

Re: (UPDATE) 150 Merc top end Miss

Have you tried running from a different fuel tank? Like a 3-6 gallon remote tank, eliminate the idea of a blocked fuel pick-up inside the tank.<br />Figure out how to test the power packs. Check all of your grounds, look for corrision. The last problem I had was with the wiring harness pulg inside the cowling,it had corroded and shorted out between the pin and burnt them,(like an ignition swich will do)causing then engine to die. Pull the connection apart and take a look, only takes 5 minutes.

 

[LubeDude]

Re: (UPDATE) 150 Merc top end Miss

Thanks guys, You have no idea how much your replies are apriciated! The fact that the engine ran so good for a breif moment, then just went to crap leads me to think that it could be a connection problem!! I did have my wife hold the steering for a minute and pumped the bulb but it made no difference at all! I do have access to a remote tank I could use for a test! <br /><br />The tank is plastic and there is a new filter on it!! I tried to look at the pickup tube but it would not come out of the tank! I (dumb) didnt think to try to blow through it though when I had it disconnected! Like I mentioned, I took the carbs off and cleaned them, but they were very clean to start with, No broken floats! The level also looked good! I have a receipt that shows the carbs to have been rebuilt last year at this time! Alone with a new fuel pump!<br /><br />Ill check the connections again and run it on the remote tank next test!<br /><br />I also think I am going to run premix as I just do not trust the plastic gear on this old motor!<br /><br />Before all this started I had just mentioned to my wife how good the motor was running!! I guess the boat Gods heard me!!<br />Im convinced that it is just something like electrical or fuel as the compression is even at 120 all the way accross!! <br /><br />LubrDude