Volvo Penta 5.7 GSi dies when jumping b+b/w wires for timing?

CLi87

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Hi there, I have a new to me 1997 Volvo Penta 5.7 GSi i've been working on, finally got everything put together and the engine runs smooth, I'm trying to check the timing and for this TBI engine I believe you just jump the black + black/white wires at the 10-pin diagnostic port at the front, but the issue is every time I jump the wires, the engine just dies. I take the jumper off and the engine will crank back up on the first key turn. Any ideas?
 

alldodge

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Unable to say for sure but that would be correct for a Merc with a MEFI3

Try increasing RPM to 1000 before connecting
 

CLi87

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Unable to say for sure but that would be correct for a Merc with a MEFI3

Try increasing RPM to 1000 before connecting
So that was the other odd thing about this boat, it's a 1997 Chris Craft 25 Concept w/ DPS drive and as far as I can tell, there's no way to rev the boat in neutral?

And I also read conflicting information about the RPMs, it seems with Mercs you're supposed to rev to 1800 RPMs before putting it in base timing mode? but Volvo Penta is supposed to be 1000 RPMs?
 

alldodge

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There is a way to rev in neutral, all motors can do it. Just need to figure out how

Thinking to usual method is not there (push button in at bottom center of handle)
Grab the bottom of the throttle handle (the hole handle) and pull out, The handle might pull out and if it does, then move forward for throttle only

If that doesn't work post pic of handle
 

CLi87

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There is a way to rev in neutral, all motors can do it. Just need to figure out how

Thinking to usual method is not there (push button in at bottom center of handle)
Grab the bottom of the throttle handle (the hole handle) and pull out, The handle might pull out and if it does, then move forward for throttle only

If that doesn't work post pic of handle
I tried every which way and can't find the neutral switch, I attached some pics, there are also 2 buttons under the handle that I can't figure out what they do either
 

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alldodge

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The neutral button has been snapped off. Many try to remove the button without breaking but don't know how so it gets snapped off.

Take a small Phillips screw driver and put it in the hole. Push it in a bit and see if it goes into throttle only mode. If it works you can then take it apart. Only problem is finding parts, their probably made I just don't know where to look
 

CLi87

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The neutral button has been snapped off. Many try to remove the button without breaking but don't know how so it gets snapped off.

Take a small Phillips screw driver and put it in the hole. Push it in a bit and see if it goes into throttle only mode. If it works you can then take it apart. Only problem is finding parts, their probably made I just don't know where to look
Yup you were right, I pushed a screwdriver in there and was able to go to neutral, I tried revving it up to 1200 rpms and it still died when I put the jumper pin in, do you think it's ok to go up to 1800 rpms on muffs and then try it?
 

alldodge

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If your on a hose then 1800 is pushing it. Do think there is a problem but right now don't know what it is, but thinking the ECM

Might ring out the wires with an ohm meter to verify
 
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