1960 JOHNSON 40HP

NASCARKP44

Recruit
Joined
Jul 25, 2000
Messages
5
HEY I NEED HELP MY 40HP MOTOR RUNS FINE AT IDLE BUT WHEN I GIVE IT THE GAS AT HIGH SPEED IT JUST HAS NO POWER AT HALF OR FULL THROTTLE. I PUT NEW PLUGS-POINTS-COND.SET COMP AT 0.22 PLAYED WITH HIGH SPEED. NOTHING IT DID RUN FINE BEFORE I PUT THE POINTS IN MAYBE SOMETHING I DID IN THERE ? PLEASE HELP IF YOU CAN THANKS BRUCE
 

Capt DHD

Seaman
Joined
Jun 17, 2000
Messages
62
Re: 1960 JOHNSON 40HP

Hello Bruce;<br />I am not sure if I can help but I'll give it a try.<br />First, did you change both points & condensers? And what brand did you use?<br />I ask this because there are 2 tune-up kits available that will fit but they are differant.(OMC pt#'s 172522 & 172523) the differance in the kits is the condensers. I do not have a chart in front of me right now, put your model # on this board and I can advise you of the correct #. If you have the wrong condensers, this could cause a problem.<br />Make sure you use a OEM (OMC) tune up kit. My expierence with aftermarket is not real good.<br />Set your points at .020 <br />If you have made an adjustment to your high speed needle, set it back to 3/4 turn out, and fine tune it on the water/tank.<br />Good Luck Rob
 

NASCARKP44

Recruit
Joined
Jul 25, 2000
Messages
5
Re: 1960 JOHNSON 40HP

HEY ROB THANKS YA ITS A AFTER MARKET [systematch F1281-1] BUT PLAYING AROUND THEY BOTH ARE GETTING SPARK..BUT I CAN TAKE THE TOP PLUG WIRE OFF AND IT RUNS THE SAME..SO COULD IT BE GAS..COMPRESS..I WILL CHECK COMP. ON MONDAY BUT HOW DO I CHECK FOR GAS ..WHEN I TAKE THE BOTTOM WIRE OFF IT WONT EVEN START SO ITS GOT TO BE SOMETHING ON THE TOP CYLINDER ?? THANKS AGAIN FOR THE HELP BRUCE
 

Capt DHD

Seaman
Joined
Jun 17, 2000
Messages
62
Re: 1960 JOHNSON 40HP

Hi Bruce;<br />If you can pull your top plug wire off and nothing changes I would still look for an ignition problem. Make sure all your wires are tight and nothing is grounding out that shouldn't. Sometimes a cylinder will fire well on a spark checker but will not fire well while under compression. When you remove the wire while running you should have some reaction.<br />This engine has only one carb feeding 2 cylinders, generally if it is a carb/fuel problem it will be with both cylinders. the only things isolating the 2 are; <br />1) Seals, when you replaced the points was there a lot of oil in the area? if so your top seal could be leaking causing the #1 cyl to misfire. <br />2) Reeds, if the reeds are not opening or closing properly can cause your problem. To inspect these properly you will have to remove the intake plate, not really to difficult, but you will need a couple of gaskets. Look to see if they are moving freely and closing all the way. don't put to muck pressure on them. <br />3) Ignition, points, coils & wires, which we have covered.<br />Keep fighting the battle.<br />Good Luck, Rob
 
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