Question about Spark Plug wire order

[rtpassini]

this is a total noob question....

my spark plug wires are labeled 1-4. There is also a number stamped near each spark plug hole.

The wires go from 1 at the top to 4 at the bottom, but they dont match up with whats stamped on the block. Is this normal? I never changed them and will be firing it up for the first time since i bought it.
its a 71 merc 800....

 

[lowkee]

Re: Question about Spark Plug wire order

The number on the wires doesn't matter, although someone may have used the wrong wire for the wrong plug when installing new wires. The important part is the order in which they come off the distributor and hook to the plug.

For example, I have a 3.0L IO with a firing order of 1342 (if I recall..). This means the wires should be connected from my distributor plug 1, then (in a clockwise direction on the distributor, though your engine may be counterclockwise) plug 3, plug 4, plug 2. The wires are just wires in this case. Sort of like any extension cord works to power any light. It is the socket it comes from that is important.

Check you manual for the firing order of your engine and which direction (clockwise or counter) your distributor rotates.

As for the number on the wires, they may be labeled per cylinder because they are different lengths and the numbers are to help you with which length best fits each span.

 

[cr2k]

Re: Question about Spark Plug wire order

If the wires are marked and seem to fit top to bottom then they are probably right. Any numbers on the block would not signify cylinder location.

Firing order is 1-3-4-2 top cyl is #1 and so on, even on a v4

 

[Chris1956]

Re: Question about Spark Plug wire order

I beleive the distributor cap has cylinder number molded onto it. Use these markings to set the wires correctly.

 

[rtpassini]

Re: Question about Spark Plug wire order

no markings on the cap...the firing order is 1324. but that doesnt help me since i dont know which they are on the distributor. i couldnt find anything in the manual either. so im hoping they are right. haha.

 

[Chris1956]

Re: Question about Spark Plug wire order

OK, Set them the old fashioned way. Set the motor to a bit before TDC and see which wire teh rotor is pointing to. Mark that as #1. Then check the others, in the direction the rotor turns.