Evinrude V4 140hp fuelpressure ?

**Toffy** · 09-08-2010, 06:12 AM

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What is the required fuelpressure on a stock early 90’s Evinrude V4 looper 140hp ?

What happens if fuelpressure is too low ?<O

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What happens if fuelpressure is too high ?
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Thanks,<O

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T.

**Toffy** · 09-10-2010, 11:11 AM

anyone ?
This should be easy questions but my service manual doesn't mention a exact value for pressure nor flow.
Basic element in my fuelsupply setup is the external Holley fuelpump. I see this is a rotative volumetric vane pump. As these Marine Holley's come in a few varyties I'd like to check if the previous owner did a good job selecting the correct one.

Therefore my questions, what happens if fuelpressure is too low/too high ? And what is the safe way to go ?
My guess is that low fuelpressure could cause powerhead damage as there is not enough lubrification ??

Any reply is welcome. Thx, T.

**flabum1017** · 09-10-2010, 11:18 AM

from what I remember, 6 - 7 psi, low pressure will starve the motor/ lean it out. too much pressure will not let the needles seat and flood the motor.