crank no start after head gasket. 2008 3.O Mercruiser.

havoc_squad

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Ayuh,...... Welcome Aboard,....... It's a simple pass-through switch,......

The switch either makes, or breaks the circuit,.......
Ignition power comes from the key switch, through the safety(mob) switch, to the motor,......

Curve ball conversation about the key switch, didn't expect that when the conversation was mostly about the ignition at the motor and that there was 12 volts at the coil.
 

Bondo

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Ayuh,..... Didn't mean to throw a curve ball,.....

Just answerin' the question in post # 18,......
 

achris

More fish than mountain goat
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When you said 'kill switch', what are you asking about? The interrupt switch that 'kills' the ignition momentarily as you shift out of gear, or the switch that shuts the engine down if you get thrown overboard?
 

alldodge

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In previous post you had 12.39V on the purple wire so I don't see an issue with a kill switch.

Is the rotor turning when the motor is cranked?
 

jeepxjmike

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Thats what was thinking the purple wire is feed 12.39 volts from kill switch.
hit on off on off a bunch times it works like it should.
coil has good ground.
rotor turns
new coil same no spark from coil to dist.
using inline spark tester.
tach disconnected.
i ran down the manual 26 page 59 60.
very helpfull in trouble shooting, still no spark form coil.
 

havoc_squad

Senior Chief Petty Officer
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Thats what was thinking the purple wire is feed 12.39 volts from kill switch.
hit on off on off a bunch times it works like it should.
coil has good ground.
rotor turns
new coil same no spark from coil to dist.
using inline spark tester.
tach disconnected.
i ran down the manual 26 page 59 60.
very helpfull in trouble shooting, still no spark form coil.

Where in the diagnostic flow chart of the service manual did you end up on? You didn't mention the exact steps taken based on the results of chart.

All I see in new information is rotor turns, tach disconnected, and new coil.

We need those details put in order to see what might have been missed.

Example:

Steps

1, no spark
1A, no spark
2A, no spark
3, both terminals more than 10 volts
4, over 10 volts, steady light
5, etc
6, etc.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Thats what was thinking the purple wire is feed 12.39 volts from kill switch.
hit on off on off a bunch times it works like it should.
coil has good ground.
rotor turns
new coil same no spark from coil to dist.
using inline spark tester.
tach disconnected.
i ran down the manual 26 page 59 60.
very helpfull in trouble shooting, still no spark form coil.

Define what you mean by the coil has good ground

The negative side of the coil is triggered by the ICM in the dizzy. which is just an on/of switch which is what fires the coil
 

jeepxjmike

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At this point I really don't know after the flow chart.
i had a spare as well as spare distributor.
At this point I think the boat is better suited as a bon fire.
 

jeepxjmike

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Distributor module replaced.
 

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Scott Danforth

Grumpy Vintage Moderator still playing with boats
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My guess is you have something wired wrong. Such as the coil negative wired directly to ground
 

alldodge

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Where in the diagnostic flow chart of the service manual did you end up on? You didn't mention the exact steps taken based on the results of chart.

All I see in new information is rotor turns, tach disconnected, and new coil.

We need those details put in order to see what might have been missed.

Example:

Steps

1, no spark
1A, no spark
2A, no spark
3, both terminals more than 10 volts
4, over 10 volts, steady light
5, etc
6, etc.

At this point I really don't know after the flow chart.
i had a spare as well as spare distributor.

Have 2 distributors and they both have no spark
Have went thru the test flow diagram and found no faults

Think you need to reassess your testing procedures
 

jeepxjmike

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I now have spark. It turns out it was a bad distributor module.
I have spark, i guess i should be happy, now the most I get is back fire.
I while valve cover was off i did adjust lash on the rockers after rotation.
The rod would spin freely. I set to 0 lash then 3/4 turn.

To much on lifters ? Where they will not open and close?
The distributor module is from a 2002 merc not my 2008.
 
Last edited:

achris

More fish than mountain goat
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Has the distributor been out? If so, a backfire though the carb is USUALLY an indicator that you're 180 degrees out.

...I while valve cover was off i did adjust lash on the rockers after rotation.
The rod would spin freely. I set to 0 lash then 3/4 turn....

Not the best way to do it. You can often spin the pushrod, even when there's load on it (as much as half a turn of the rocker nut). The best way is to be lifting the rod up and down to find the zero lash point.

Chris.....
 
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jeepxjmike

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I have not moved distributor, only cap.
i guess im over concerned of a loose rods.
I will loosen rods and try.


I Reviewed timing by putting #1 cylinder at tdc.
compression felt by cylinder top of block.
aligned dizzy to #1 cylinder.
 

achris

More fish than mountain goat
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Messages
27,468
Also check that you have the plug wires going to the right place, and assuming the correct direction of rotation of the distributor. (If you assume the wrong direction, 1 and 4 will be correct, 2 and 3 will be 'crossed')

Chris......
 

alldodge

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The rod would spin freely. I set to 0 lash then 3/4 turn.

The spinning is not what your feeling for to set zero lash. While rotating the rod back n forth, move it up and down. Once all the up/down is gone, this is zero lash
 

jeepxjmike

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The spinning is not what your feeling for to set zero lash. While rotating the rod back n forth, move it up and down. Once all the up/down is gone, this is zero lash

To set 0 lash would I move the rod up and down till no movement? Then turn 3/4 turn?
I guess it's ok for the rocker arm to have wiggle room left to right?
 

Bondo

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To set 0 lash would I move the rod up and down till no movement? Then turn 3/4 turn?
I guess it's ok for the rocker arm to have wiggle room left to right?

Yes,...... 'n Yes,......
 
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