Fuel pressure loss at high rpm
05-05-2018 | 02:20 PM
#21
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05-05-2018 | 03:39 PM
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05-05-2018 | 03:42 PM
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I guess at this point it has to be either the pick up or carb. I just can’t wrap my head around how it could be the pick up since I’ve tried it directly out of a gas can with same issue. I don’t know much about carbs either so not really sure if that logical but easy enough to be worth a try.
05-05-2018 | 05:54 PM
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I have replaced the upper with a stock one. I’m not aware of any upgrades for that. Same thing on the other engine. Doesn’t seem to be any bearing play. Pulley rotates easy and no wobble. Belt tension is good but really don’t know how to tell if it’s slipping at rpm. I will put a new one on and try it. Thanks.
05-05-2018 | 07:05 PM
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I guess at this point it has to be either the pick up or carb. I just can’t wrap my head around how it could be the pick up since I’ve tried it directly out of a gas can with same issue. I don’t know much about carbs either so not really sure if that logical but easy enough to be worth a try.
I would replace the fuel lines. Marine fuel lines are different than auto. Marine lines have to be vapor impermeable. Marine lines have a liner that can come lose and cause a restriction or worse come apart and plug filters, injectors etc.
05-05-2018 | 10:50 PM
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Whenever I lost pressure, it was a dirty/plugged filter. I run Fuel/Water sep > 100 micron > pump > 10 micron > dist block w/ return regulator > carb. Is a filter getting dirty? (This is on an electric pump setup).
ALSO, I just noticed one of my lines might be getting restricted coming out of the bulkhead, turning 90deg. I saw it dropping on the gauge last time out, but put the boat away before I could determine root cause. (Filters looked good when I changed them).
Check to make sure you have smooth transitions, and no kinks or collapsing. For it to happen on only one, something is being restricted, or the pump is whooped? (Some of this sounds elementary, which you have probably already checked).
ALSO, I just noticed one of my lines might be getting restricted coming out of the bulkhead, turning 90deg. I saw it dropping on the gauge last time out, but put the boat away before I could determine root cause. (Filters looked good when I changed them).
Check to make sure you have smooth transitions, and no kinks or collapsing. For it to happen on only one, something is being restricted, or the pump is whooped? (Some of this sounds elementary, which you have probably already checked).
05-05-2018 | 10:54 PM
#29
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I doubt it would be the carb. With such a drastic drop in pressure would indicate a stuck float and dumping a lot of gas in the engine. It would bog down and you would have black smoke and stall.
I would replace the fuel lines. Marine fuel lines are different than auto. Marine lines have to be vapor impermeable. Marine lines have a liner that can come lose and cause a restriction or worse come apart and plug filters, injectors etc.
I would replace the fuel lines. Marine fuel lines are different than auto. Marine lines have to be vapor impermeable. Marine lines have a liner that can come lose and cause a restriction or worse come apart and plug filters, injectors etc.
