mbroughton02
Petty Officer 2nd Class
- Joined
- Jan 17, 2015
- Messages
- 198
Hello everyone. Please watch my video. Here's the story with my boat motor:
This boat sat in my girlfriend's father's shed for 15 years. He gave her / us the boat last fall. It's a 1988 Smoker Craft aluminum fishing boat with this 28hp Evinrude (also a 1988). He and I got the motor running last fall with little more than fresh gas, a new battery, new spark plugs, temporarily bypassing a faulty neutral start switch, and some cranking. We took it out exactly once before it got too cold. It ran smoothly, but was a bear to keep running when cold and it seemed like it wasn't getting to the top of the RPM range when wide open.
So I rebuilt the carb. It is easier to start now, and I don't know about the wide open RPM because the lake here is still iced over. But now I have this "stumbling" condition. This happens intermittently at idle all the way up to perhaps 1,500-2,000 RPM (boat does not have a tach, so I'm guessing), and I haven't run the motor faster than that in the barrel. The engine does whether it is warmed up or not, but again, it is intermittent. It was fine for 5 minutes, then it will do this, then it won't.
I don't remember this from the one time I ran the boat in the fall, but it is possible that it was happening. I'm a total newbie to boats, but not small engines. I think I was overstimulated / excited when I took the boat out in the fall and may have not noticed everything that wasn't quite right.
Here's a full list of what I did to the motor over the winter:
1) Carb rebuild. Followed instructions in factory service manual to a T. And I have rebuilt plenty of smaller carbs before. I did manage to break the head off of idle adjustment screw while trying to get the starter off, which you have to do to get the carb off on this motor. This was NOT the low speed needle on the carb. This is a plastic screw under the flywheel on the port side. I replaced it with OEM and turned it to exactly (or damn close) where the old one was (I counted the threads).
2) New Impeller
3) New lower unit oil
4) New shift rod coupler that I stripped out trying to put the linkage back together. I swear I am not usually so clumsy / careless.
5) New hose for tell-tale, and new fitting for the exit end. When we took the boat out in the fall there was water leaking all over the place and gathering in the "pan" the powerhead sits in.
6) Did the "link & sync" described in the factory service manual, up until the spark advance part where I need a test wheel and timing light. I have neither, but I have considered doing the "Joe Reeves method" of checking the timing while cranking the engine with the starter. Still need a timing light, though.
Things I have not done:
1) Pulled flywheel & inspected points / whatever is under there. I don't have much experience with ignition systems, but I do have the factory service manual...
2) Tested spark with a spark tester.
3) Aforementioned timing check
4) Checked compression. I have a compression tester, I just haven't gotten to it yet.
5) ???
So, what gives? Is this a misfire, a skip, or a lean condition? Or something I haven't considered. Help please!
This boat sat in my girlfriend's father's shed for 15 years. He gave her / us the boat last fall. It's a 1988 Smoker Craft aluminum fishing boat with this 28hp Evinrude (also a 1988). He and I got the motor running last fall with little more than fresh gas, a new battery, new spark plugs, temporarily bypassing a faulty neutral start switch, and some cranking. We took it out exactly once before it got too cold. It ran smoothly, but was a bear to keep running when cold and it seemed like it wasn't getting to the top of the RPM range when wide open.
So I rebuilt the carb. It is easier to start now, and I don't know about the wide open RPM because the lake here is still iced over. But now I have this "stumbling" condition. This happens intermittently at idle all the way up to perhaps 1,500-2,000 RPM (boat does not have a tach, so I'm guessing), and I haven't run the motor faster than that in the barrel. The engine does whether it is warmed up or not, but again, it is intermittent. It was fine for 5 minutes, then it will do this, then it won't.
I don't remember this from the one time I ran the boat in the fall, but it is possible that it was happening. I'm a total newbie to boats, but not small engines. I think I was overstimulated / excited when I took the boat out in the fall and may have not noticed everything that wasn't quite right.
Here's a full list of what I did to the motor over the winter:
1) Carb rebuild. Followed instructions in factory service manual to a T. And I have rebuilt plenty of smaller carbs before. I did manage to break the head off of idle adjustment screw while trying to get the starter off, which you have to do to get the carb off on this motor. This was NOT the low speed needle on the carb. This is a plastic screw under the flywheel on the port side. I replaced it with OEM and turned it to exactly (or damn close) where the old one was (I counted the threads).
2) New Impeller
3) New lower unit oil
4) New shift rod coupler that I stripped out trying to put the linkage back together. I swear I am not usually so clumsy / careless.
5) New hose for tell-tale, and new fitting for the exit end. When we took the boat out in the fall there was water leaking all over the place and gathering in the "pan" the powerhead sits in.
6) Did the "link & sync" described in the factory service manual, up until the spark advance part where I need a test wheel and timing light. I have neither, but I have considered doing the "Joe Reeves method" of checking the timing while cranking the engine with the starter. Still need a timing light, though.
Things I have not done:
1) Pulled flywheel & inspected points / whatever is under there. I don't have much experience with ignition systems, but I do have the factory service manual...
2) Tested spark with a spark tester.
3) Aforementioned timing check
4) Checked compression. I have a compression tester, I just haven't gotten to it yet.
5) ???
So, what gives? Is this a misfire, a skip, or a lean condition? Or something I haven't considered. Help please!
