9.8 merc fuel bulb gets soft motor runs hot

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Colorado1135
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9.8 merc fuel bulb gets soft motor runs hot

Post by Colorado1135 » 05 Jul 2016, 13:11

any ideas as to what it could be?
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KMixson
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9.8 merc fuel bulb gets soft motor runs hot

Post by KMixson » 05 Jul 2016, 14:01

Does the fuel primer bulb get hard when you pump it with the engine not running? The fuel bulb not getting hard would indicate the float bowl needle valve not sealing completely. If it gets hard the needle valve would appear to be working correctly in my opinion. With the engine running the bulb may not get as hard as with the engine off because there is fuel flowing through the needle valve to keep it running.

The motor running hot would indicate a worn or bad impeller or a lean condition on the carburetor. Remember rich is cool and lean is hot. It is much better to be a little rich than to be too lean on the carburetor adjustment. Too lean can destroy your engine. Does it run at the rated RPM's OK? There are others on here that may be able to help you more than me and are familiar with your specific engine. Good Luck.

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Colorado1135
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9.8 merc fuel bulb gets soft motor runs hot

Post by Colorado1135 » 05 Jul 2016, 14:15

Thank you for your reply. the bulb gets hard when I prime it to start, when I run it at higher speed it gets soft and the motor dies after just a little ways. when I prime it again it's as though it had no fuel at all in the line. I switched tanks and hoses but it still does it. it will idle ok, but it does get hot. it seems to be peeing out enough water, it's just hot to the touch, almost too hot to touch for more than a second.
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KMixson
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9.8 merc fuel bulb gets soft motor runs hot

Post by KMixson » 05 Jul 2016, 14:44

There could be trash and/or debris in your carb. It may need a cleaning. It may idle well because the fuel needed to keep it running is not that great. Then when you rev it up up to a higher RPM it can't get enough fuel to keep it running. That would be my first order of business if it were mine.

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Colorado1135
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9.8 merc fuel bulb gets soft motor runs hot

Post by Colorado1135 » 05 Jul 2016, 15:14

could that also be causing it to run hotter than normal? I would think so if it's not getting the oil from the mixed fuel.

I'll try that first, thank you!
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KMixson
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9.8 merc fuel bulb gets soft motor runs hot

Post by KMixson » 05 Jul 2016, 15:34

Yes, it could be running hotter because it is leaning out as it runs out of fuel.

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