'81 Rude 15 hp stalling

[Bergy37]

Hiya. Took my boat out for the first time and had some problems with my outboard. It's a 1981 Evinrude E15RCIS 15hp. When I bought it, the PO showed me that he had replaced the female fuel line connector that attaches to the tank. He included 2 old OMC 6 gallon gas cans that looked pretty rough. He also gave me receipts for the service he had done in the last month, water pump replacement, carb service, and de-winterization.
So I get it started and it idles okay, just needed an occasional tap on the throttle. After letting it idle for a minute, I closed the choke and it continued to idle just fine. As soon as I opened the throttle 1/4, it sputtered and died. To keep the story short, I'll summarize from here. Every restart happened on first pull and idle was good, but every 10-15 seconds I had to tap the gas to keep from stalling. A few times when I got to 1/4 throttle, it reved up nice, then sputtered, then reved, then died. First check on the bulb indicated that it took another 2 pumps to get it hard again. This happened quite a few more times. There was a 1/4" gap in the connection at the tank. I tightened it up, but it would soon go back to that same gap from the vibration.
When I got home, I pulled out the extra tank which still had good pressure in it and connected the fuel line. I could hear a hissing where air was escaping the connection. So either the connection that was replaced is bad, both connections on the gas tanks are bad, or all three. I'm heading to the local marina shop to get a new plastic tank, fuel line hose, and an extra connector. I've also just picked up a large can of SeaFoam to run through.
Now my questions: Is the air in the fuel line the reason why it stalled? Is it normal for the connections to go bad on these old gas cans? Lastly...despite the recent carb cleaning the PO had done, would it be a good idea to run the SeaFoam to eliminate that as a possibility
Thanks in advance for any help. I'll be in frequently, so I can answer any questions you may have.

 

[omcnut]

Re: '81 Rude 15 hp stalling

gday mate as far as i know a 81 15 hp jhonnyrude should not have a pressure tank it sounds like fuel starvation are your tank vents open if not vacum could be preventing fuel flow also try pumping the fuel bulb while its running and your trying to rev it the fuel pump may be faulty or the filter screen in the pump blocked by debris from the old metal tanks(rust ect.)a plastic tank is a good idea..

 

[OptsyEagle]

Re: '81 Rude 15 hp stalling

Now my questions: Is the air in the fuel line the reason why it stalled? Is it normal for the connections to go bad on these old gas cans? Lastly...despite the recent carb cleaning the PO had done, would it be a good idea to run the SeaFoam to eliminate that as a possibility

You certainly sound like you have a fuel starvation problem. That usually is a result of either, a faulty fuel pump, a faulty fuel hose, no venting of fuel tank or an air leak. So to answer your question about the air leak being the problem ... maybe. Since you have most likely already bought a new tank, hose and connector, snap them on and give it a try. There is about a 75% chance one of them was the culprit and your problem has now been resolved.

If your carb is already dirty, seafoam is unlikely to clean it by simply putting it in the gas or spraying it through the carb throat. You would need to dissassemble, clean and rebuild with a carb kit. It does not sound like you have a carb problem at this time, but it is a remote possibility.

As I said, report back after trying the new items you acquired.

 

[Bergy37]

Re: '81 Rude 15 hp stalling

I won't be able to get the new can and connectors until Wednesday. However, when I went out to empty the boat before today's rain, I found the gas can spitting gas out like a water fountain. The cap was tight and the temps were getting warmer, so I assume pressure built up and the gasket couldn't hold the gas back. In the pic below, the green circle is where the gas was spewing from. As for the 2 pins circled in yellow...do those open the inner seal to let gas flow when depressed? When I connected the fuel line to the 2nd tank, air hissed out between the line and tank connections when they were depressed. Looks like a new tank is my best bet. A new fuel line assembly also looks like a good idea since I can't get a tight connection.

 

[OptsyEagle]

Re: '81 Rude 15 hp stalling

I don't recall seeing those little posts before. I have a newer plastic gas can and I am pretty sure they only have the fuel connector and guide/lock beside it, but I am going by memory.

It sounds like your tank may not be venting and if the tank heats up the weakest link for the pressure must have been through those posts. A non-venting tank would create the problems you are having.

 

[Bergy37]

Re: '81 Rude 15 hp stalling

New plastic tank, new fuel line with new connectors.....same problem. Decided to try the seafoam treatment I read about in here, and got to the point where I shut the motor down and let the cleaner work for 5 minutes. While waiting, I removed the cover and followed the fuel line to the filter housing. Here is where I saw that the plastic hose clamp looked loose. As soon as I touched it, it fell into 2 pieces. Got a new one and installed it.
I was going to continue with the seafoam treatment, but when I went to fish out the old clamp pieces, I saw what is in the pic below. A spring and some yellow plastic piece chillin. I'm pretty confident the plastic piece was on the shifter assembly as a screw cap. The spring.....I have no clue. With my luck, it will have nothing to do with the bogging and be the start of a whole new problem. A positive though...found an old outboard mechanic on craigslist selling original OMC service manuals for $20, so I ordered the one for my motor.
If anyone has any ideas, it would be greatly appreciated. Thanks.