dutch oldie seahorse looses power after 20 minutes

ckwantes

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Jun 15, 2004
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got an old johnson seahorse 2hp (70-ies) from a friend. It starts (too?) easy. First no problems. After 20 minutes, opening the gashandle results in loosing power (like running on a hill with car). When putting the engine "in free" (no rotating prop) the problem fades away for a few secs, after putting egine in forward (rotating prop) the problem returns. The 2 bougies (ignation) look quite dark. Does anyone have an idea?<br />Thanks
 

JB

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Mar 25, 2001
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Re: dutch oldie seahorse looses power after 20 minutes

Hi, Chris.<br /><br />Welcome to iboats. :) <br /><br />Some of what you say is confusing because it doesn't sound like any 2hp Johnson I am familiar with.<br /><br />Please give us the model number off of the mounting bracket plate.
 

rwise

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Re: dutch oldie seahorse looses power after 20 minutes

sounds like it may not be keeping enuf (enough) fuel in the carb. just a thought.
 

ckwantes

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Re: dutch oldie seahorse looses power after 20 minutes

excuse me.<br />i was a bit confusing:<br />it is a 2 stroke, 2 cilindre, SIX HP engine (or 5, i dont know exactly). This wil clear a lot. I can check the serial number, but perhaps this explenation already explains a lot.<br /><br />Yesterday did some testing.<br />Turning the central lean-rich-screw till it was totaly closed (perhaps the fuelinput was too rich). Didn't change anything at he motor. When a turned and pulled it out, I saw there was no rubber thing on the end of the "needle"/conus (as was told to me as it should be). Could this be the answer?
 

ckwantes

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Re: dutch oldie seahorse looses power after 20 minutes

serial nr: <br /><br />6 RL 720<br />B 20868
 

rwise

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Re: dutch oldie seahorse looses power after 20 minutes

if you can turn the adjustment for fuel air mix completly closed, and it makes no differance in the way the engine runs, I would clean and rebiuld the carb! Dont know about there, but here a kit runs about $20. When I done the carb on my 1958 35hp I found a rubber washer inside the carb that was crumbling away and stopping up the main jet! <br />I could br wrong but I think the rubber for the needle will stay in the carb when the adjustment needle is removed.
 

ckwantes

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Re: dutch oldie seahorse looses power after 20 minutes

today I showed the engine to a mechanic: turns out to be water in the cilindres too. The lean-rich screw happens to be the adjustment for the stationary-fuelsupply. So i indeed closed this one, but kept giving fuel by keeping the gashandle above stationary rpm. So at least I didn't had a miracle in my hands. I'm afraid this oldie is going to be terminal... Or don't you agree on this one?<br />thanks anyway for the response..
 
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