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Mercruiser 4.3 Vordem V6 Engine Firing order

H

Haulinzilla

New member
I bought a boat with a V6 Vortex. I wanted to do a tune up so I went to a Marine shop and obtained the firing order diagram. Turns out my engine has the #3 wire from the distributor going to the #4 cylinder, and the #4 wire from distributor going to the #3 cylinder. The boat runs, and the timing is right on the mark. However, boats stalls out sometimes like its not getting gas. This is why I started to do a tune up. How can this run right and be timed if those plug wires swapped on #3 & #4?
 
checking the timing typically calls for making the measurement on cylinder #1...

If the ignition wires are connected in the wrong order, the engine won't run correctly....especially under a load...

You didn't say how you made the determination of 'running right' so there are still lots of unknowns...
 
As far as having two cylinders (#3 on one side and #4 on ofher side of engine) spark plug wires reversed,

It is well known that the V8 gm spark plug firing order can have this mistake occur and show mininal effect on idle and in some cases operation.
(There is in fact two cyclinders for V8 that the spark plug wires can be swapped and it actually may increase perfromance- not by a significant amount but by a little)

In your case l, The reason is the actual spark timing vs cam timing and piston position is so close the engine can run "smoothly" but may not perform as well as it should.
 
kghost said:
As far as having two cylinders (#3 on one side and #4 on ofher side of engine) spark plug wires reversed,

It is well known that the V8 gm spark plug firing order can have this mistake occur and show mininal effect on idle and in some cases operation.
(There is in fact two cyclinders for V8 that the spark plug wires can be swapped and it actually may increase perfromance- not by a significant amount but by a little)

In your case l, The reason is the actual spark timing vs cam timing and piston position is so close the engine can run "smoothly" but may not perform as well as it should.
Click to expand...
Makes sense. It runs good when its running. I think I found the problem with it stalling...vac line on back of carb was pinched. Thank you!
 
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