eavega
Lieutenant
- Joined
- Apr 29, 2008
- Messages
- 1,377
I put my 15' Yarcraft Yankee powered with my '72 50 HP Evinrude (90273C) on the lake on Sunday, and had a qualified success. I did have a couple of issues i was hoping for some help on:
1. When you do the carburetor adjustments, the motor should be in neutral, right? The motor would not idle in neutral at lower than 1800 or so RPMs, but would purr like a kitten when in gear between 2000 and 4400 RPMs (max I could get at WOT, that is a separate subject I have posted on the propeller board). I wanted to do the carb adjustments, but didn't know if I was supposed to be in gear, or in neutral. Having to rev the motor so high made changing gears challenging to say the least, and I avoided doing that to not cause any undue stress to the LU until I get the idle issue resolved.
2. With engine speed at 4400 RPMs, the motor sounded very smooth; no skipping, sneezing, bouncing, etc. I was getting about 20 MPH by GPS. That is going to be enough for my needs (note, the hull is rated for 70 HP max), but I was concerned about lugging the motor, since its WOT should be 5500-6500. Is a step down to a 15p prop the right correction for that, or is there something else I need to do to verify that I am, in fact, getting maximum power at WOT? Motor has good spark verified using a spark tester, and compression at 140 per cylinder, dead even.
3. After about a couple of hours of running on the lake, starting, stopping, futzing with the carbs trying to adjust the idle (too many waves/wakes from other boats to make those adjustments!) we were heading back to the ramp when I lost power and the motor conked out. A quick check showed me the priming bulb had gone flat and sucked in hard. I disconnected the fuel line from the motor and tank, and the bulb sprang back. I was able to prime the motor again, and got it running for a little bit (enough to get back to the ramp) and again, motor conked out with the priming bulb hard and flat. Where is the most likely place to look for a problem? I figure since the bulb was flat, the fuel pump was working, but with no fuel getting through, its either the one-way valve through the bulb, the connector to the tank, or the fuel pick up tube. Tank and fuel line are relatively new (its one of those 6 gallon attwood tanks they sell at wal-mart and its prepackaged fuel line, purchased about 3 years ago), fuel was fresh and has been as long as I have used that tank, but it did have stabilized premixed fuel that sat in it for about 10 months until I emptied it just prior to working on this motor.
I am so close here! Other than the idle setting, it really is "good enough" for my needs, but if I can get this rig tuned just right so I can concentrate on bustin' bass and a little pleasure cruising with the family I would be a happy man. Any help or advice is greatly appreciated.
Rgds
Eric
1. When you do the carburetor adjustments, the motor should be in neutral, right? The motor would not idle in neutral at lower than 1800 or so RPMs, but would purr like a kitten when in gear between 2000 and 4400 RPMs (max I could get at WOT, that is a separate subject I have posted on the propeller board). I wanted to do the carb adjustments, but didn't know if I was supposed to be in gear, or in neutral. Having to rev the motor so high made changing gears challenging to say the least, and I avoided doing that to not cause any undue stress to the LU until I get the idle issue resolved.
2. With engine speed at 4400 RPMs, the motor sounded very smooth; no skipping, sneezing, bouncing, etc. I was getting about 20 MPH by GPS. That is going to be enough for my needs (note, the hull is rated for 70 HP max), but I was concerned about lugging the motor, since its WOT should be 5500-6500. Is a step down to a 15p prop the right correction for that, or is there something else I need to do to verify that I am, in fact, getting maximum power at WOT? Motor has good spark verified using a spark tester, and compression at 140 per cylinder, dead even.
3. After about a couple of hours of running on the lake, starting, stopping, futzing with the carbs trying to adjust the idle (too many waves/wakes from other boats to make those adjustments!) we were heading back to the ramp when I lost power and the motor conked out. A quick check showed me the priming bulb had gone flat and sucked in hard. I disconnected the fuel line from the motor and tank, and the bulb sprang back. I was able to prime the motor again, and got it running for a little bit (enough to get back to the ramp) and again, motor conked out with the priming bulb hard and flat. Where is the most likely place to look for a problem? I figure since the bulb was flat, the fuel pump was working, but with no fuel getting through, its either the one-way valve through the bulb, the connector to the tank, or the fuel pick up tube. Tank and fuel line are relatively new (its one of those 6 gallon attwood tanks they sell at wal-mart and its prepackaged fuel line, purchased about 3 years ago), fuel was fresh and has been as long as I have used that tank, but it did have stabilized premixed fuel that sat in it for about 10 months until I emptied it just prior to working on this motor.
I am so close here! Other than the idle setting, it really is "good enough" for my needs, but if I can get this rig tuned just right so I can concentrate on bustin' bass and a little pleasure cruising with the family I would be a happy man. Any help or advice is greatly appreciated.
Rgds
Eric