• Mobile App For Android Now Online!

    Download it here. The app is searchable in the Google Play Store under Sailboat Owners.

    Sorry iPhone/iPad users, we are still waiting on Apple. :(

    Click the X in the upper right corner to make this go away

YANMAR 4JH3TE Slow throttle response when hot

Jul 23, 2009
366
Beneteau 31 Oceanis Grand Lake, Oklahoma
I once had a riding mower that would intermittently suffer from fuel starvation. It seemed to do it on the hottest days, seemed heat related. After much rebuilding, cleaning, replacing & cursing I finally found a fuel line that had failed internally. It looked fine and would flow fuel most of the time but not always. Never had any more trouble after I replaced that line.
 
Jun 15, 2012
536
Hunter 50 AC Greenport, NY
Normal temperature on my Hunter 50 is 165 degrees. I think 180 degrees is too hot. Over the last weekend towing a large dingy swamped with water and the outboard in the down position (outboard off) I was running 170-173 degrees.
 
Aug 9, 2019
12
Hunter 460 Maryland
Fuel tank vent is wide open. It's right next to the fuel fill and I can hear the fuel gurgling while I fill the tank...I've also shot some of the fuel foam out the vent before, so I know it's open.
 
Jul 23, 2009
366
Beneteau 31 Oceanis Grand Lake, Oklahoma
After reading through the links above it really sounds like you have a problem with the governor inside the injector pump.
 
Aug 9, 2019
12
Hunter 460 Maryland
Normal temperature on my Hunter 50 is 165 degrees. I think 180 degrees is too hot. Over the last weekend towing a large dingy swamped with water and the outboard in the down position (outboard off) I was running 170-173 degrees.
What engine does your Hunter 50 have in it? I haven't ruled out a hot engine. I still need to do a flush of the engine coolant and punch all of the cooling bundles - check for flow etc.
 
Jun 15, 2012
536
Hunter 50 AC Greenport, NY
If you are 110 percent sure that fuel is not the problem, I think it boils down to engine temperature (too hot) or air leak when hot or the turbo. I think easiest thing to do is check engine temp with an infrared non contact sensor to check accuracy of gauge. If sensor concurs with gauge I would remove thermostat and see if temp decreases.