1989 Evinrude 30 2-stroke losing power at high RPMs

[bigb56]

Have had issues with this motor off and on for that past 10 years, latest is losing power at high or full throttle. I rebuilt the carb today but there was nothing wrong with it, looked as good as when I rebuilt it 4-5 years ago. I also replaced the fuel pump although taking the old one apart everything looked fine, I had put a kit in it when I did the carb. When I got to the plugs I found them to be wet. I also found them to be L77JC4 plugs which are for the 35 HP, I had L82C plugs in it which are called for on the 30 HP (which ours is) and are one heat range hotter. My son had someone give it a "tune up" last year and he is the one that put those plugs in. I am hoping that is all that is wrong, I have attached a pic to see if you guys think they are wet enough to affect firing, or if being colder that could be an issue. I can only get the L82C in a resistor plug right now (RL82C) but should not matter right?

 

[racerone]

Have installed a new impeller recently ?----Test run with another tank and hose ?

 

[bigb56]

Have installed a new impeller recently ?----Test run with another tank and hose ?

The guy who did the tune up did impeller, new oil in lower unit and plugs (last year) and the motor has only been run for a few trips since then. Been trying different tanks and hoses, new fittings on motor etc. Bought all new best we could find about 6 years ago. Thinking about splicing in a clear filter to see if fuel is starving though.

 

[racerone]

The issue is not the plugs !----Does spark jump a gap of 7/16" on both leads on a test device ?----Run with a timing light one cylinder at a time.----See how spark behaves at full throttle.-----I am thinking there may be an issue with bottom crankshaft seal.----But I can not see or hear your motor.

 

[bigb56]

The issue is not the plugs !----Does spark jump a gap of 7/16" on both leads on a test device ?----Run with a timing light one cylinder at a time.----See how spark behaves at full throttle.-----I am thinking there may be an issue with bottom crankshaft seal.----But I can not see or hear your motor.

Had not considered the crank seals. Will check spark again today, unfortunately I can only test in driveway with muffs so no load or full throttle.
There is an accumulation of oily residue inside the lower engine housing but no signs of soot, would that be indicative of a leaking lower crank seal? Or would it go directly into the lower unit?

 

[bigb56]

I have found the closest thing to a smoking gun yet....I removed the fuel pickup to epoxy over the gauge window which was leaking, I found the pickup tube to be a very loose fit on the upper nipple and in fact it fell off as I lifted it out of the tank. So I fixed it with a fuel injection clamp. Secondly when I emptied the tank I found water, lots of it. I had just filled that tank yesterday and we had emptied it into a gas can so there wasn't much left in the bottom, the water I found was nearly 4 quarts but I am thinking some of that must be ethanol that attached itself to the water that was in the tank?
Second question, I now have a leak on top at the small round part I am pointing at with the stick, it pushes fuel out when the tank is closed and expands. Is there supposed to be a breather there or can I epoxy it shut?

 

[racerone]

Looks like sparkplugs were not at fault.----I do not like plastic tanks.-----I prefer the metal tanks from the 1960's and 70's.

 

[tphoyt]

That supposed to be the tank vent and it’s broken. You need to vent the tank or it will leak when it expands and it will keep your motor from running as well if its closed.
I only close mine durning transport in my truck. You should get a new tank or at least replace the sending unit.

 

[bigb56]

That supposed to be the tank vent and it’s broken. You need to vent the tank or it will leak when it expands and it will keep your motor from running as well if its closed.
I only close mine durning transport in my truck. You should get a new tank or at least replace the sending unit.

I know about the vent on the cap, this is different, it's on the fuel pickup and gauge assembly, nothing is broken off, that's how it looked when I bought it new 5 years ago. It just didn't leak then.

 

[tphoyt]

I could be wrong but I have seen a few that look like that. I believe there made by Atwood.

 

[bigb56]

I could be wrong but I have seen a few that look like that. I believe there made by Atwood.

This one is an Evinrude. Was not cheap even for plastic. Probably Chinesium.

 

[bigb56]

Sealed the cracked plastic with JB Weld and this year the boat ran better than it ever has. Blamed the motor all this time when it was contaminated fuel and a broken pickup tube.