Hello,
I have a 1986 OMC Cobra 3.0L 4cyl Stern Drive.
I bought it last year, and rode around for about 2 months...maybe 20 hours of total drive time.
Then, I followed the Youtube video we've probably all seen in one form or another on how to winterize the boat and followed the instructions. I did, however, leave the gas (with marine fuel stabilizer) in the tank over the winter about 1/2 full.
A week ago, I pulled it out and had some troubleshooting to do with the oil and some cracked gaskets, so on the hose it went and during all this troubleshooting, the engine started fine and would idle for as long as I wished. No problem.
I then go to take it out for a ride today, put some 93 Octane fuel in it (11 gallons) and all of a sudden, after about 2 minutes of riding, it stalls...turn it over and no gas (just that awfully disappointing dry turning of the starter). I bring it home, hook it up to the hose and start with everything I can think of.
Two interesting things came out of my observations:
1) I had planned to suck the gas out and start fresh...So, I couldn't think of a good way to get to the tank other than the sending unit, so I took one of the screws out and it was like Old Faithful...A gas geyser! I thought...hmm, that's strange...better let that settle down, so I did.
2) I notice that if I loosen the top plate of the carburetor, the engine will start and run rough (obviously...the carburetor is half off!)....But, once the carburetor is screwed down tight, the engine fails and acts like it's getting no gas. Also, if you press it down so that the engine dies and then let it go, there's a noticeable swoooooosh sound (like a vacuum seal) that occurs when it's pulled up.
I've taken the fuel line off at the output of the fuel pump and turned the engine...I see plenty of gas pour out.
I've checked the fuel pump filter....Looks good to me.
I did put some of that Permatex Form-A-Gasket on the edge of the carburetor....
However, I guess my question is 'why would adding gas now make the carburetor so sensitive? do they really prefer running on old sour winter gas instead of fresh clean 93 octane?'
Follow up question is 'how do i fix this?'
Thanks!
I have a 1986 OMC Cobra 3.0L 4cyl Stern Drive.
I bought it last year, and rode around for about 2 months...maybe 20 hours of total drive time.
Then, I followed the Youtube video we've probably all seen in one form or another on how to winterize the boat and followed the instructions. I did, however, leave the gas (with marine fuel stabilizer) in the tank over the winter about 1/2 full.
A week ago, I pulled it out and had some troubleshooting to do with the oil and some cracked gaskets, so on the hose it went and during all this troubleshooting, the engine started fine and would idle for as long as I wished. No problem.
I then go to take it out for a ride today, put some 93 Octane fuel in it (11 gallons) and all of a sudden, after about 2 minutes of riding, it stalls...turn it over and no gas (just that awfully disappointing dry turning of the starter). I bring it home, hook it up to the hose and start with everything I can think of.
Two interesting things came out of my observations:
1) I had planned to suck the gas out and start fresh...So, I couldn't think of a good way to get to the tank other than the sending unit, so I took one of the screws out and it was like Old Faithful...A gas geyser! I thought...hmm, that's strange...better let that settle down, so I did.
2) I notice that if I loosen the top plate of the carburetor, the engine will start and run rough (obviously...the carburetor is half off!)....But, once the carburetor is screwed down tight, the engine fails and acts like it's getting no gas. Also, if you press it down so that the engine dies and then let it go, there's a noticeable swoooooosh sound (like a vacuum seal) that occurs when it's pulled up.
I've taken the fuel line off at the output of the fuel pump and turned the engine...I see plenty of gas pour out.
I've checked the fuel pump filter....Looks good to me.
I did put some of that Permatex Form-A-Gasket on the edge of the carburetor....
However, I guess my question is 'why would adding gas now make the carburetor so sensitive? do they really prefer running on old sour winter gas instead of fresh clean 93 octane?'
Follow up question is 'how do i fix this?'
Thanks!