Loss of power at full throttle-revisited

[MOTAS]

I just replaced the VRO for a new one and added oil to the gas tank as recommended.<br />Problem of loss of power of this 200 Johnson/89 has been partially solved. Now power has increasd but reaches only 3800 RPM and for moments accelerates to 4500 RPM. Also after a 30 minutes shut off of the engine ( Stop for lunch) it starts easy but COUGHING AND SNEEZING, it stops as soon as I engage forward and it takes time to return to normal operation. Are these symtoms related to the rich mixture of oil/gas? <br />(Remember it has new ignition, new coils, rebuilt carbs,new plugs....) <br />Thank you for your reply.

 

[petryshyn]

Re: Loss of power at full throttle-revisited

>compression OK?<br />>water in fuel? drain a carb into a glass and look...<br />>have you tried with kill wire disconnected? if partially grounded can cause misfire<br />>is the tach accurate?<br />>have you kept squeezing the primer bulb and kept it good and hard at wide open throttle operation? (I mean actually held it tight, not just pumped up once) this will eliminate fuel pump<br />>what did you replace in the ignition system as far as components?<br />>did you closely inspect each and every water tight connector for pins pushed back in their boot? (had one last summer)<br />>does it smoke? <br />>have you tried other plugs? I've seen defective new ones<br />>a leaking plug wire to ground often gives misfire at WOT. While idling, soak down each coil and plug wire with the wife's spray water bottle. Do one at a time. If it starts missing when you hit a component, you know which one is at fault.<br />>intermitent problems are tough to find. do all the charge coil and trigger tests to verify high enough voltage levels.<br />>next time you're out, locate a flammable WD-40 and spray in the carbs while cruising.(or try engaging the primer) If speed picks up drastically, you'll know its fuel starvation.<br /><br />Good luck!

 

[clanton]

Re: Loss of power at full throttle-revisited

When you start on the ignition system, check the flywheel magnets, they may be loose, broken, and if recently reglued may be in backwards.

 

[wakatoa]

Re: Loss of power at full throttle-revisited

My 70 hp Johnson was acting like that and it turned out to be a faulty float valve.

 

[MOTAS]

Re: Loss of power at full throttle-revisited

Dear Schematic:<br />-No water in fuel, I have a filter with transparent bowl.<br />-Kill switch is disconnected.<br />-Tach is OK.<br />-Primer pump is new but becomes soft very easy. I blew backward and is leaking, so I will replace it again. The small plastic filter that is installed just before the VRO shows air inside, is that normal? I know that new engines have a gas separator, what's for?<br />-I replaced the timer base & 2 of 6 coils. Power pack was replaced 50 hours ago.<br />-I will check the connectors as recommended.<br />-It was smoking, but I put more gas in the tank to reduce the richness of the mixture and it improved. Of course I checked first that the VRO was delivering oil.<br />-I will replace the plugs again.<br />-Will go with my wife and her spray to make the test.<br />Thank you.

 

[petryshyn]

Re: Loss of power at full throttle-revisited

>compression OK?<br />>next time you're out, locate a flammable WD-40 and spray in the carbs while cruising.(or try engaging the primer) If speed picks up drastically, you'll know its fuel starvation.<br />>now you got me nervous....bypass the VRO and draw from a fresh tank of 50:1 premix (with good grade TCW-3) This will eliminate the change of bad mixtures.<br />>check clanton's post as well! he's usually right on!<br /> <br />Good luck! <br />

 

[MOTAS]

Re: Loss of power at full throttle-revisited

Thank you guys. Will reply this weekend.

 

[MOTAS]

Re: Loss of power at full throttle-revisited

Today Engine ran perfect for one hour until I turned it off. After 30 minutes of engine stopped, it was very hard to run again, it started and died, started and died..... as soon as I engaged forward. I checked the plugs and 5 were wet and one dry and black. I was in the middle of the sea, ate one battery trying to start, and finally it worked but hesitating and with less power. I pumped the gas bulb with no positive result.<br />Could this be a coil problem or a powerpack failure? In neutral it accelerates ok.<br />I sprayed water to the coils and cables, but nothing happened. Only problem that I noticed when I disconnected the plugs one by one is that spark is stronger in a couple of cylinders, and engine seems not to be affected when I disconnect any plug.<br />All the magnets behind the flywheel are ok.<br />Thank you for your advise. <br />What is the normal time that a technician can charge to make a diagnostic? Last time I paid 12 hours and here I am.