91 Johnson Seahorse 140 Stalling (Tampa)

[Allen McGhn]

This is my first boat, and the engine ran great at first, on the third trip out the motor just choked and died while running at 75% throttle. The engine will start for a few seconds to a minute and then it dies. It's more like a sudden halt instead of a wind down. If I let it sit to a minute it will start right back up and do the same thing? Looking at the post I may need to check the compression but where would I get the tools to do that? I know engine's but I don't know outboards. Please help.

 

[CJ ROOSTER]

Re: 91 Johnson Seahorse 140 Stalling (Tampa)

allen, if you go to a local auto parts store you can pick up a compresion tester for about $20.00. just follow the instruction on tester.<br /><br /><br />cj rooster

 

[Navigator]

Re: 91 Johnson Seahorse 140 Stalling (Tampa)

Allen,<br />When it dies, it the fuel primer bulb hard? You may have a weak diaphram in the fuel pump and when it gets hot, it stops pumping. Also check for venting of the fuel lines. You may have a restriction thats keeping the fuel pump from getting fuel.<br /><br />This would be my starting point.<br />Nav

<br /><br />------------------<br />Sold the Force and bought my Honda...Oh how I miss those days of Screaming at my Outboard.

 

[Allen McGhn]

Re: 91 Johnson Seahorse 140 Stalling (Tampa)

Thanks for the info, I'm on my way to NAPA to buy a compression testor. As far as fuel pump, I thought of that too, the fuel filter doesn't show any air bubbles. And while the bulb isn't totally hard it isn't that soft either, I tried to keep the engine running by continuing to pump the bulb with the engine running to no avail. I'm going to try disconnecting the line from the fuel pump to see if the fuel is pumping out. Thanks again.

 

[crazyray2]

Re: 91 Johnson Seahorse 140 Stalling (Tampa)

will motor turn over at same speed after it cranks or is it tight?.....does it still have spark?.......more details = better answers.......

 

[Allen McGhn]

Re: 91 Johnson Seahorse 140 Stalling (Tampa)

OK, I tested compression and I had 124, 121, 120, 121. I tested the fuel pump and it spits plenty of fuel. The engine doesn't seem to lock up tight but it might be, maybe overheating? I talked to the person that sold me the boat and they never replaced the water pump impeller. They owned the boat for 6 years and only took it out about 8 times. They may have put 40 total hours on the engine but they don't know if the impeller was ever replaced. How do I know if the impeller is pumping enough water? And as a failsafe, would it be a good idea to just replace it anyways? If that is the case where the heck is it on the motor? Thanks for everyones advise.<br /><br />Allen

 

[Mark-C]

Re: 91 Johnson Seahorse 140 Stalling (Tampa)

That's fine compression. You should replace the impeller. It's at the top of the lower unit. Get a manual for instructions about doing it right. But I doubt that's your problem---not long enough to overheat. It doesn't sound like fuel starvation either, since you say it's sudden. Sudden stops are often electrical; with a fuel problem you often get spontaneous acceleration, then a sputtering death. <br /><br />It could be some kinda overheat sensor gone bad---if it's shutting down just as it gets a little warm, maybe the sensor is doing that. I don't know this engine, so I don't know where to tell you to look.<br /><br />If it doesn't start right after shutting down, that's actually useful: you can check to see if there's spark at the plug wires then, to see if that's really the problem.

 

[Allen McGhn]

Re: 91 Johnson Seahorse 140 Stalling (Tampa)

Well I'm going to try to replace the water pump, even if that's not the problem I'm sure it needs it. I took off the lower bolts but I cant figure out how to disconnect the shifting linkage. I can see a bolt on the fulcrum of the shifting arm but I can't see how to remove it. How can I possibly disconnect the linkage or is it as impossible as it looks without pulling the motor?