volvo penta 7.4 GL , engine wont start after line in prop

flyhigh123

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1996 Volvo Penta DP 7.4GL Gasser

got troll lines tangled in prop, heavy gauge lines.

boat was put in reverse by mistake by friend which tangled the lines. when still in reverse, we shut the engine off to avoid losing our gear.

After clearing the lines, we start the engine. It putters for a few seconds and right when i put into gear it died.

from then on it wouldn't start. the engine turns over, no battery issues.

got towed back.

When i turn on the power to the engine, i dont hear the fuel pump on. I unplugged the fuel pump power and put a multi meter to the power line, didnt get a volt reading. thought maybe the relay, swapped a new relay( Hella 4RA), still the same.

What am I suppose to read off of the power line to the fuel pump? Is it suppose to read 12v?


I'm going to try to power the fuel pump direct from a 12v source and see if it makes any sound. anyone know which side is positive/negative?

I'm going to drop it off to the mechanic as I'm not exp in motor work.

thought i'd ask here to see your thoughts.
 

bruceb58

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Mar 5, 2006
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30,454
You won't read voltage to the fuel pump unless the engine is cranking or running. Put a couple ounces a fuel down your carb throat. If it still doesn't start, its not your fuel pump.

Turning the engine off in reverse likely did not cause your issue unless you some water came up your exhaust and got some of your spark plugs wet.
 
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flyhigh123

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Nov 17, 2012
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You won't read voltage to the fuel pump unless the engine is cranking or running. Put a couple ounces a fuel down your carb throat. If it still doesn't start, its not your fuel pump.

Turning the engine off in reverse likely did not cause your issue unless you some water came up your exhaust and got some of your spark plugs wet.



ok. so remove the top filter, put a few ounces directly into the carb. do i need to spray it in? Will try that and see if it fires up.
 

bruceb58

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Nope just pour a little in the throat. Make sure you blower is running and your face is not near the carb.
 

flyhigh123

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Nov 17, 2012
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I put fuel in carb, it fired up. So we know engine is ok. Fuel pump, i removed it and put a 12V 3.5A power direct to the pump, it made no sound. It seems like the fuel pump died or could be an electrical issue. Have the fuel pump on order and will work through this.
 

bruceb58

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For future reference, you can pull out the fuel pump relay and jump between pins 30 and 87 to apply power to the pump. Pin 30 gets power from a 12.5A circuit breaker. Pin 87 goes to the pump.
 

flyhigh123

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Nov 17, 2012
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there is a red breaker, 12.5 that is below the normal 3 red ones. this one is slightly hidden at the bottom.

How do i know when these red breakers trip? Reason I ask is the hidden one, i pushed it, it barely moved but made a click. Normally when my other breakers pop, its very loose and when i reset it, i know its reset. This one, barely moved but clicked so I wasnt sure if its just loose or that breaker did pop?

Thanks!
 

flyhigh123

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Nov 17, 2012
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SUCCESS!!!! Thank you for all the tips! It was the fuel pump that went bad. I guess the bottom breaker triped and the fuel pump was the culprit. Swapped it out and it fired up!

Thanks again!
 
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