Mercury 60HP Outboard, Which sparkplugs?

alphaechcharlie · 27 March 2009, 12:58

Hi All

I have a 1989 60hp Mercury outboard fitted to my boat, recently fitted a fixed VHF and antenna, i am getting really bad interference from the outboard when its running, speaking to a bloke the other night he thinks i can get replacement spark plugs that will sort the problem?

Any ideas ehat plugs will do the job?

regards

Marinautic · 27 March 2009, 13:33

The NGK plug will be the same number, but with a Z in it.

doggypaddle · 27 March 2009, 14:07

Thats right, but not the full picture.
R designates a restive supressor and Z an inductive resistor. You Need the Z in the right place though, If the Z is the first letter then its an extended gap plug, and if its the last letter it designates a 2.9mm electrode.
you need it in the middle! as in BP6ES,BPR6ES, and BPZ6ES being no supressor, resistive and inductive respectively.
If you get the Z in the wrong place the plug could potentially cause engine damage.
here the NGK chart so you can double check.

http://www.spark-plugs.co.uk/pages/technical/ngkjpg.htm

Marinautic · 27 March 2009, 15:40

very true.

If you have the serial # of the motor, I can tell you which plug you need.

eg, if you currently use BU8H, then you'd need BUZ8H

alphaechcharlie · 27 March 2009, 16:25

the serial number is 954927, not sure what plugs i currently have in, will pop down this weekend and have a look.

Many thanks for all you help

Marinautic · 27 March 2009, 17:34

You need NGK BUZHW