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Both engines idle rough and then die

Are you running both at the same time on the same hose?
 
Back to your fuel issue..... We now know that you have approximately 20 gallons of bad fuel. Hopefully, with the additives you've added, you will be able to burn off everything and won't see any more issues. I think that the fuel senders will show full or fuller than normal if water or ethanol is present.
 
Murf'n'surf said:
Are you running both at the same time on the same hose?
Click to expand...
Heavens no, one at a time. I may be mechanically inept, but I spend all my spare time on the forum and so I am at least well read!
 
The water flow difference might be that the thermostat hasn't opened yet and thus more more is passed through the exhaust.
 
Murf'n'surf said:
Back to your fuel issue..... We now know that you have approximately 20 gallons of bad fuel. Hopefully, with the additives you've added, you will be able to burn off everything and won't see any more issues. I think that the fuel senders will show full or fuller than normal if water or ethanol is present.
Click to expand...

@Murf'n'surf would you recommend that I go ahead with the plan to change the spark plugs once I get a chance to burn through this tank of fuel? That is only 2 hours at WOT!!
 
Murf'n'surf said:
The water flow difference might be that the thermostat hasn't opened yet and thus more more is passed through the exhaust.
Click to expand...

So not necessarily abnormal?
 
See how it runs after another 1/2 tank of fuel. If you need them you'll notice surging in rpm's at idle and speed. You could also lose top end rpm's.
 
Stefan Fromm said:
So not necessarily abnormal?
Click to expand...
Not sure but if you are not overheating I wouldn't worry.

You could look for pinched hoses in behind the motor.
 
I am sorry I missed out on this conversation! It was a doozie! Glad you got them running @Stefan Fromm , these guys used to amaze me, but not anymore...we have the most willing to help of anywhere I have ever seen.

I can help on one topic being discussed. The water flow from the pee holes when running an engine on the hose is irregular and unpredictable boat to boat. And the hose from the port side engine is considerably longer, making it harder for it to even show any flow at all. My '08 rarely showed any flow on the hose. Even when I would nudge the throttle to around 5K rpm to warm my oil for an oil change, I didn't get any flow from my pee holes. So I wouldn't worry about that at all. But I would damn sure want to see good flow from all of them when running at cruise on the water!

Glad you found the issue on the rough running. Now to the plug change. My fingers are crossed and I have said a prayer to the Boat Gods that the plugs come out in one piece. I guess we don't need to say how important annual spark plug changes are and the need to use anti-seize on the threads. Apparently the previous owner didn't. Also, don't use a torque wrench on them. Hand tighten with the extension but no ratchet, and then turn 1/4 to 1/2 turn more with the ratchet...and your done. They will come out easy next year. Fingers crossed!
 
txav8r said:
I am sorry I missed out on this conversation! It was a doozie! Glad you got them running @Stefan Fromm , these guys used to amaze me, but not anymore...we have the most willing to help of anywhere I have ever seen.

I can help on one topic being discussed. The water flow from the pee holes when running an engine on the hose is irregular and unpredictable boat to boat. And the hose from the port side engine is considerably longer, making it harder for it to even show any flow at all. My '08 rarely showed any flow on the hose. Even when I would nudge the throttle to around 5K rpm to warm my oil for an oil change, I didn't get any flow from my pee holes. So I wouldn't worry about that at all. But I would damn sure want to see good flow from all of them when running at cruise on the water!

Glad you found the issue on the rough running. Now to the plug change. My fingers are crossed and I have said a prayer to the Boat Gods that the plugs come out in one piece. I guess we don't need to say how important annual spark plug changes are and the need to use anti-seize on the threads. Apparently the previous owner didn't. Also, don't use a torque wrench on them. Hand tighten with the extension but no ratchet, and then turn 1/4 to 1/2 turn more with the ratchet...and your done. They will come out easy next year. Fingers crossed!
Click to expand...

Hey @txav8r welcome to the party. My water flow question wasn't in relation to the pee holes but rather the exhaust port next to the jet nozzle.
 
That's right @txav8r .... The stuck spark plug.
Try removing that stuck spark when the motor is cold. Don't over torque it! I did and had to get the head removed and repaired.
 
That will teach me not to speed read!
 
Murf'n'surf said:
That's right @txav8r .... The stuck spark plug.
Try removing that stuck spark when the motor is cold. Don't over torque it! I did and had to get the head removed and repaired.
Click to expand...

I don't like the sounds of that.
 
Run your fuel out and get that problem solved before moving on to the sparks!
 
Im glad it worked out. Bad gas is a PITA, specially when it comes from a fresh fill up. I have learned when to buy and when not, first when not is do not buy from Marinas that sit idle all winter, wait till the first big weekend (for me it is Mothers Day) to pass before tempting what is in their tanks. Same with gas stations, if the big truck is there refueling them, wait a good 30 min after they are done or find another station. They stir up sediment and water and if you pump while they are filling you will likely be pumping that crud into your tank.
 
I'm not boat savy like you guys and am still learning a lot about my boat but I am an old car gear head... where and how are the fuel pumps arranged in these boats? Is it one submerged fuel pump in the tank or does each engine have there own pump? It sounds like a fuel problem. If he has a long clear plastic tube he could run in through the gas cap all the way into the bottom of the tank .. hold your thumb over the other end and pull it out... let it all drain out in a 5 gallon bucket and look closely at it.. you may be able to see water in the depending on how the boat and fuel are setting..
 
Stefan, I would also urge you to pull the air cleaners and look for oil on the filters. I think someone mentioned that but not sure if you have had a chance. Over filling the oil will cause some to come back up and soak the filters. It would be odd for that to happen to both engines, however.
 
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