Have Question 1975 25 horse evinrude

[yeagermeister]

I own a 1975 25 horse evinrude.I've replaced the 2 ignition coils , spark plugs and wires.The motor will start but it wants to run on one piston.If I move the plug wire on more or off it starts running on two piston.I started it in the dark and saw the spark arcing to the outside of the plug so I cleaned and checked the grounds.Ran good for a while but now its doing the same thing.Can anyone help me figure this out.

 

[Vic.S]

Re: Have Question 1975 25 horse evinrude

sounds as though you have dodgy plug or lead. Swap the plugs over and see if the problem moves with the plug. Swap the leads over and see if the problem moves with the lead.

Been known for plug leads to short against the casing. Dont know if that can happen to yours. look.

Oh heck the plug leads are integral with the coils. Check the terminal inside the plug cap. Could still swap the whole coil assemblies over.

 

[F_R]

Re: Have Question 1975 25 horse evinrude

So, is it still arcing down the side of the plug? If so, replace the boot. You can get them separately without the whole wire. Once they arc, they carbon track and it is hard to keep it from doing it again.

 

[yeagermeister]

Re: Have Question 1975 25 horse evinrude

I appreciate the response.I swapped the plug wires and it looks like it is still arcing on the same one.I even swapped the coils and same thing.Do you think it is the boots and plug wires still?Can the points or timing cause the spark to be to strong , which would cause the arc out?The gap in one plug also gets smaller when I run it.I have ordered a manual but still waiting.Must get on water before this drives me batty