1995 p150 pulser coil testing. Motor no power under load.

[mrgraphix]

Can you check the pulser coil with it still on the motor? the motor has no power carbs cleaned and adjusted new feul pumps. with the high idle lever the motor will rev to 5900 but put it in the water and 2400 and sounds boggy. it wants to die at idle. if you catch it before it dies and tap the electric choke it will run for a few more seconds then try to die again. I checked the oms on the pulser coil as per the manual all three omes readings came back as follows 140 138 140 this was with the coil still installed. getting fire to all plugs. I am lost I just bought the boat last week and have yet to get it to runn right. new fuel. compression 96-100 on all cylinders. timing adjusted per the manual. one plug wire was out of spec and I trimmed it back and is now testing good. new NGK plugs gapped at 38 thou. I was told that someone had rebuilt the carbs 2 years ago. to me it acts like fuel starved runs when the choke is tapped fuel line prime bulb gets firm. filter seperator emptied and was clean no water. the jets inthe float bowls are 2 different number jets oen is a 130 th other looks like a 126 or 136 with one goes on the port side. I put the 130 on the staboard side just like it came out but I was not hte first one to have them apart so i was just wondering??
I know there are a lot of questions here but i just tried to be as clear as possable on the thing that i have done. any help sugestions would be great.

 

[mrgraphix]

Re: 1995 p150 pulser coil testing. Motor no power under load.

I found the jet information in the manual. I is in the spec section not the fuel section where I was looking. cleaned and checked th carbs again. took it out to the lake left the breather off I can watch the feul come up out of the meter into the carbs feul flow looks good. even on all cylinders. still no power will not rev past 2000-2400 while in gear. revs with the high idle. still dies at about 1000 rpm and wont idle. I am still wondering about the pulser coil testing. all i checked was the ohms is there any other test that i can do. sparks do seem weak while cranking. I pulled all of the plug wires one at a time while it was running at the lake the spark jumed 1/2 inch while it was running this fast. I checked the timing by the book 18 degrees advance and 7 degrees retard. I just don't know what else to do. please some one give me your thoughts about where to go from here. I wish I could afford to just take it to the shop and let someone else fix it but I just bought it and don't have enough left to pay fo a big shop bill. thanks for reading this and all help is appreciated

thanks Steve

 

[Ray Neudecker]

Re: 1995 p150 pulser coil testing. Motor no power under load.

When compression is good and a Yamaha fires, you go to fuel as you have done.
It has all of the symptoms of fuel starvation. First replace the filter on the fuel water seperator. They are not always stopped up by water and the stoppage is often not visisble. Run the motor on a small seperate tank to eliminate the fuel tank itself and the anti siphon valve.
The timing should be 22-23 degrees at WOT. Good luck. You are on the right path.

 

[mrgraphix]

Re: 1995 p150 pulser coil testing. Motor no power under load.

its alive! its alive! I tried the small fuel supply no change. increased the WOT timing no change. I thought check for a dead cylinder while it was running I started pulling plug wires to check for spark. all had spark then I noticed that when I pulled one of the wires the engine lost even more power. when I pulled a different wire no change so i moved the plugs I put the one that caused a decrease in power in the cylinder with no change and the other plug back in the good cylinder. the dead cyinder followed the plug. these were new plugs as it turned out 3 of the six were bad. Back to the dealer with three bad plugs in hand. told him what i had done he looked at me confused he said on rare occasion they get a bad plug but three at one time was very unusual. he said it has to be a fuel problem An I would have to go thru the carbs again. I spent six hours soaking cleaning checking and resetting to spec these carbs I told him that it could not be fuel. he took the plugs over to an engine that they had in the shop hooked them up and guess what no fire. so he gave me three to replace them I went a head and bought three more so I wolud have some spares. came home changed all 6 plugs to the new ones. started it up WOW it runs I had to back the idle down. No more miss no more stalling. So off to the lake. I unloaded the boat it sat and idled great. let her warm up a bit turned out and let her go. up on plane without a problem 56mph before a backed her down came to a stop and she continued to idle. thanks for the help and I hope this may help someone else in the future. now it is time to go and play.