mercury 1500 150hp serial 3915265

[inrover1]

ive got this mercury 1500 150 hp inline six that starts great and idles great but when i shift into forward gear and go wide open throttle engine wont get over 1800 rpm or so like the throttle isnt working or adjusted correctly i can unhook throttle cable and advance timing by hand while also opening butterflies on carburaters engine opens up and runs like i think it should <br />when i shift into reverse and go WOT engine tachs up and runs fine also. something i did notice while making the short distance back to dock in forward there seemed to be a pretty heavy blue smoke, however my premix was 4 oz heavy oil isnt this possible reason for heavy smoke Any information that can be given to me on these problems is greatly appreciated

 

[Bear]

Re: mercury 1500 150hp serial 3915265

ive got this '74 mercury 1500 150 hp inline six...<br /><br />If you need to know <br /><br />Edit:<br />I think you need a manual.<br /><br />Heavy oil? Are you using TCW-III oil and a 50:1 mix?<br />Are you using the right spark plugs? Are they new?

 

[Gold Bear]

Re: mercury 1500 150hp serial 3915265

inrover1 <br /><br />With your engine not running, move the control lever to wide open throttle, then look and see if the carb butterflys are inline with the bore of each carb. The butterflys should be straight in-line with the carb bore so there is maximum air flow.<br /><br />There are several adjustments that should be made, that are best done with the aid of a service manual.<br /><br />Mix the fuel and oil at 50:1 ratio. Actually, I use a mix of about 40:1 in my 1972, 115 Merc and learn to live with the smoke. "I love the smell of pre-mix in the morning...it smells like victory".<br /><br />Good luck,<br /><br />Gold Bear