150 merc.not running well

[jadatt]

I got it out forthe first time in 21/2 yrs. and cleaned the carbs. and oil tanks put in new opil and gas. <br />It won't rev.up with out stalling out, it sputters, coughs, and dies when you try to go full throtle. the alarm comes on in an itermitten signal. when it is running it won't rev up above 1100 rpm's ingear, it will rev up in neuteral, but seems to be missing. <br />This is an 84 or 85 150 xr2 with oil injection.

 

[Clams Canino]

Re: 150 merc.not running well

10 -1 the carbs gummed up from sitting. VERY common.<br /><br />-W

 

[jadatt]

Re: 150 merc.not running well

Have pulled the carbs and cleaned them all. All the needle seats seem to be in good condition and working and cleaned the reed valves. It will only run about 1100 rpms in gear and runs like it is missing. Go to throttle it and it dies.

 

[gss036]

Re: 150 merc.not running well

Mix a very strong mixture ( maybe 2 bottles) of Techron or SeaFoam with about 3 gl gas and run it. Slow running will clean low speed jets and above 3000 will do the high speed jets. The engine has fixed jets. Worth a try

 

[outboard tech]

Re: 150 merc.not running well

Some of the earlier v6's had carb floats that can loose ability to "float".(not sure about yours, but easy to check) They could saturate and sink in the bowl and flood you out, even when propperly set up. You'd see a lot of smoke, and fuel pouring out stan tubes in the carb venturies. A torn fuel pump diaphragm is also possible, reirc hoses off/broken,lot's of possibilities. The intermittant alarm should be addressed--overheat? And all your clear oil tubing should be replaced if it hasn't been in the last 5 years or so. It will be brittle and can easily break.

 

[jadatt]

Re: 150 merc.not running well

Thanks for the response and I'll try it all , the clear oil tubing has been replaced. There isn't a lot of smoke, but will check the fuel pump also. thank you

 

[Winger Ed.]

Re: 150 merc.not running well

The kit to rebuild the fuel pump is surprisingly cheap. I'd re-do it just because it probably hasn't been done in several years, and the diaphrams do stretch with age. When stretched out like they get, they work, but can't deliver enough flow at higher speeds or load requirements.<br /><br />If you're not getting a 'normal' amount of smoke, I'd have a look at the oil injection system. Lots of folks a whole lot smarter then I am swear by them,,, but personally, I just don't trust them after they're a few years old and out of warranty. <br /><br />If Mercury isn't liable for it not working,,, I sure hate to gamble my engine on the darn thing functioning properly, knowing the price and trouble of a overhaul will be on me.