Mercury Ignition Coil Replacement for P/N 336-4528

[WarthogMan]

I just bought a 1973 Mercury 110/9.8 HP which has no spark. After testing the ignition coils, both primary windings are open so I need to replace them. The coils on the motor are P/N 336-4528 (the lime green type) but finding a replacement is tough because they are so old. There are a few on ebay but they look in pretty rough used condition and they are fairly expensive. Does anyone know of a newer replacement coil that will work and have about the same specs? It looks like there are plenty of 339 series coils out there at a reasonable price. If any of these could work, the part number would be helpful. Also, would I need to change the spark plugs? The motor currently has Champion L77JC4 plugs. I greatly appreciate any help and would like to get this motor running since it is pristine except for the ignition problem. Thanks

 

[Chris1956]

Amazon has a new one for $120.

https://www.amazon.com/dp/B00N6D93VU?tag=picclick0f-20&linkCode=osi&th=1&psc=1

Newer Merc 9.8 motors have a coil that is more avail, but just as pricey.

Coils are pretty tough. A used one probably works. A local salvage yard might allow you to exchange it if they sell you a bad one.

You could get your switchbox part number go on Sierra's web site and find motors with that switchbox and see what coil they use. I know the coil from a '73 Merc 850 and '77 Merc 1500 interchange, although they are different part numbers and size and color. They share switchboxes, stators and other ign parts.

 

[WarthogMan]

Thanks, Chris 1956. I found that coil on ebay also but I'm not sure I want to put that much into the motor, especially since I need two of them. There are plenty of new Mercury coils on ebay and amazon in the $15 to $25 range that have a similar shape and look like they will fit into the existing coil covers. I was just hoping someone out there might know which part numbers might be compatible.

 

[Faztbullet]

You have to use the lime green, red or orange coils as they are grounded internally different due to ignition system design. Newer coils will not work

 

[WarthogMan]

Thanks, Fazbullet. That helps. Does anyone know a good place to get the lime green, red, or orange coils at a reasonable cost?