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#1
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Outboard revs up then dies
Wierd thing happened this weekend.
We had been running for quite a long time on the lake. We had probably been cruising along for about 3 hours, with a couple of stops. I had started out with a full tank of gas. At about 3/4 of a tank, the motor did a weird thing. We were running at WOT at about 4200 rpm when it suddenly had more power, went to about 4400rpm for a second or two, then the engine slowly died. It tried to start a couple of times. It'd idle, but when the throttle was pushed forward it'd die. The motor wasn't hot. We ate lunch for about 20 minutes. Started the engine back up and cruised towards the marina. It died again in the same manner. Replaced the fuel filter at the Marina, but the problem came back later in the day. The fuel filter we replaced looked fine, but it was the only thing I could think of trying out there. Water is pumping through the engine. I installed a new impeller last year. I rebuilt the fuel pump at the beginning of last season. When I rebuilt the fuel pump, I checked compression and it was good to great on all cylinders. Over the winter I drained the fuel tank. I didn't figure on a condensation problem as this is Arizona. Filled it with a fresh full tank of gas this year. We had pumped the bulb when it died. The bulb still had gas in it and would pump up hard easily. Still wouldn't start. When I would accelerate, the bulb would go soft but soon harden back up again. It's a 1998 Force 75hp 2-stroke. It happened five times over the course of the weekend. Not at any serious times luckily. Any ideas what might be causing this? TIA, Buster |
#2
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Check all you fuel lines for cracks, especially near the clamps. Its normal
for the bulb to go soft when accelerating. "Buster" wrote in message ... Wierd thing happened this weekend. We had been running for quite a long time on the lake. We had probably been cruising along for about 3 hours, with a couple of stops. I had started out with a full tank of gas. At about 3/4 of a tank, the motor did a weird thing. We were running at WOT at about 4200 rpm when it suddenly had more power, went to about 4400rpm for a second or two, then the engine slowly died. It tried to start a couple of times. It'd idle, but when the throttle was pushed forward it'd die. The motor wasn't hot. We ate lunch for about 20 minutes. Started the engine back up and cruised towards the marina. It died again in the same manner. Replaced the fuel filter at the Marina, but the problem came back later in the day. The fuel filter we replaced looked fine, but it was the only thing I could think of trying out there. Water is pumping through the engine. I installed a new impeller last year. I rebuilt the fuel pump at the beginning of last season. When I rebuilt the fuel pump, I checked compression and it was good to great on all cylinders. Over the winter I drained the fuel tank. I didn't figure on a condensation problem as this is Arizona. Filled it with a fresh full tank of gas this year. We had pumped the bulb when it died. The bulb still had gas in it and would pump up hard easily. Still wouldn't start. When I would accelerate, the bulb would go soft but soon harden back up again. It's a 1998 Force 75hp 2-stroke. It happened five times over the course of the weekend. Not at any serious times luckily. Any ideas what might be causing this? TIA, Buster |
#3
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For whatever reason you are running out of gas. It revs just as it starts
to run out of fuel in the carbs and the engine runs lean for a second or so and then dies. Change the pump bulb assembly as a starting point. These can go bad and cause this problem. If that does not solve it - Check your fuel filter again. You may have picked up more trash from the tank. Last clean the carbs good. -- Tony my boats and cars at http://t.thomas.home.mchsi.com - "Buster" wrote in message ... Wierd thing happened this weekend. We had been running for quite a long time on the lake. We had probably been cruising along for about 3 hours, with a couple of stops. I had started out with a full tank of gas. At about 3/4 of a tank, the motor did a weird thing. We were running at WOT at about 4200 rpm when it suddenly had more power, went to about 4400rpm for a second or two, then the engine slowly died. It tried to start a couple of times. It'd idle, but when the throttle was pushed forward it'd die. The motor wasn't hot. We ate lunch for about 20 minutes. Started the engine back up and cruised towards the marina. It died again in the same manner. Replaced the fuel filter at the Marina, but the problem came back later in the day. The fuel filter we replaced looked fine, but it was the only thing I could think of trying out there. Water is pumping through the engine. I installed a new impeller last year. I rebuilt the fuel pump at the beginning of last season. When I rebuilt the fuel pump, I checked compression and it was good to great on all cylinders. Over the winter I drained the fuel tank. I didn't figure on a condensation problem as this is Arizona. Filled it with a fresh full tank of gas this year. We had pumped the bulb when it died. The bulb still had gas in it and would pump up hard easily. Still wouldn't start. When I would accelerate, the bulb would go soft but soon harden back up again. It's a 1998 Force 75hp 2-stroke. It happened five times over the course of the weekend. Not at any serious times luckily. Any ideas what might be causing this? TIA, Buster |
#4
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"Buster" wrote in message ... Wierd thing happened this weekend. [snip] Its running out of fuel. The increased power is from leaning out, and then it simply dies from fuel starvation. Since it just came up on you, I suspect some dirt in the carb(s) or some other fuel blockage. Good luck. -- -Netsock "It's just about going fast...that's all..." http://home.columbus.rr.com/ckg/ |
#5
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Thanks, I'll try all those things. I'll be replacing the fuel hose/bulb
assembly next trip. Actually, I just remembered something. I was on two lakes this weekend. Roosevelt and Apache in Arizona. The first day was on Roosevelt, where these problems occured. The last time it happened, we took some carb cleaner and sprayed it into the carb while the engine was running. After that I trailered over to Apache lake and the problem never cropped up again there. Apache is a much smaller lake though, so I didn't get the running time like I did on Roosevelt. I figured it was something in the fuel system, but wanted a second opinion. I guess my checks/fixes from here a 1. Replace fuel line/bulb. 2. Check vent on fuel tank. 3. Check fuel hoses under the cowl. 4. Check pickup in fuel tank 5. Clean/rebuild carb? Is it ok to run something like Berrymans 44k fuel system cleaner through the tank on a 2-stroke? Thanks, Buster "Netsock" wrote in message ... "Buster" wrote in message ... Wierd thing happened this weekend. [snip] Its running out of fuel. The increased power is from leaning out, and then it simply dies from fuel starvation. Since it just came up on you, I suspect some dirt in the carb(s) or some other fuel blockage. Good luck. -- -Netsock "It's just about going fast...that's all..." http://home.columbus.rr.com/ckg/ |
#6
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Buster wrote:
Wierd thing happened this weekend. We had been running for quite a long time on the lake. We had probably been cruising along for about 3 hours, with a couple of stops. I had started out with a full tank of gas. At about 3/4 of a tank, the motor did a weird thing. We were running at WOT at about 4200 rpm when it suddenly had more power, went to about 4400rpm for a second or two, then the engine slowly died. It tried to start a couple of times. It'd idle, but when the throttle was pushed forward it'd die. The motor wasn't hot. We ate lunch for about 20 minutes. Started the engine back up and cruised towards the marina. It died again in the same manner. Replaced the fuel filter at the Marina, but the problem came back later in the day. The fuel filter we replaced looked fine, but it was the only thing I could think of trying out there. Water is pumping through the engine. I installed a new impeller last year. I rebuilt the fuel pump at the beginning of last season. When I rebuilt the fuel pump, I checked compression and it was good to great on all cylinders. Over the winter I drained the fuel tank. I didn't figure on a condensation problem as this is Arizona. Filled it with a fresh full tank of gas this year. We had pumped the bulb when it died. The bulb still had gas in it and would pump up hard easily. Still wouldn't start. When I would accelerate, the bulb would go soft but soon harden back up again. It's a 1998 Force 75hp 2-stroke. It happened five times over the course of the weekend. Not at any serious times luckily. Any ideas what might be causing this? TIA, Buster I am no expert - I run my little 7.5 out of fuel after each use. I unplug the fuel line till it dies. Right before it dies it will increase rpm's like you mention. So to me it sounds like it is starving for fuel. Capt Jack R.. |
#7
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I would not use anything not desiged for a 2 stroke.
You stand a chance of the oil not mixing properly and blowing the engine. -- Tony my boats and cars at http://t.thomas.home.mchsi.com - "Buster" wrote in message ... Thanks, I'll try all those things. I'll be replacing the fuel hose/bulb assembly next trip. Actually, I just remembered something. I was on two lakes this weekend. Roosevelt and Apache in Arizona. The first day was on Roosevelt, where these problems occured. The last time it happened, we took some carb cleaner and sprayed it into the carb while the engine was running. After that I trailered over to Apache lake and the problem never cropped up again there. Apache is a much smaller lake though, so I didn't get the running time like I did on Roosevelt. I figured it was something in the fuel system, but wanted a second opinion. I guess my checks/fixes from here a 1. Replace fuel line/bulb. 2. Check vent on fuel tank. 3. Check fuel hoses under the cowl. 4. Check pickup in fuel tank 5. Clean/rebuild carb? Is it ok to run something like Berrymans 44k fuel system cleaner through the tank on a 2-stroke? Thanks, Buster "Netsock" wrote in message ... "Buster" wrote in message ... Wierd thing happened this weekend. [snip] Its running out of fuel. The increased power is from leaning out, and then it simply dies from fuel starvation. Since it just came up on you, I suspect some dirt in the carb(s) or some other fuel blockage. Good luck. -- -Netsock "It's just about going fast...that's all..." http://home.columbus.rr.com/ckg/ |
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