What spark plugs for a 50hp Mercury?

[freddofrog]

Hi all<br /><br />Can some tell me what the correct spark plugs are for a 50hp 4 cylinder 2 stroke outboard mercury?<br /><br />I think the serial number is 89434680 or 39434680. Not quite sure as half of the first digit is missing. I am in Australia so possibly an Aussie model?<br /><br />Year of manufacture would be useful also if you have it.<br /><br />btw, where can I get this type of info myself?<br /><br />Cheers<br />ff

 

[TwoWatt]

Re: What spark plugs for a 50hp Mercury?

Welcome to Iboats.<br /><br /><br />I just changed my plugs so I can add my 2 cents.<br /><br />Are there plugs in it? Write the brand name & the part # down & search sparkplugs . com. It will show the exact plug & cross reference to others.

 

[Dunaruna]

Re: What spark plugs for a 50hp Mercury?

Hi ff,<br /><br />The latest Australian NGK catalogue (2005) only lists 2 plugs for the 4 cyl 50hp 2 stroke, pre '77 - BUHW, POST '77 - BUHW-2.<br /><br />I think you have one too many digits in the serial number.<br /><br />Aldo

 

[andrewkafp]

Re: What spark plugs for a 50hp Mercury?

If it's an 8,it will be a Brownband or even a red stripe mid 80's Aussie motor.<br />Aussie motors started with an 8.<br />If it's a 3 it will be a Blueband USA from early 70's with 1 coil rather than 4.<br />Aldo is correct with the plug type.They are surface gap plugs.And there are only 7 digits in Merc no's<br /><br />www.marinshopen.se

 

[Dunaruna]

Re: What spark plugs for a 50hp Mercury?

Andrew, I couldn't help but notice Caloundra in your sig. What gives? You gone and done the big move?<br /><br />Aldo

 

[freddofrog]

Re: What spark plugs for a 50hp Mercury?

Hi all<br /><br />I'll check out the serial number when I get back home in a weeks time though I am pretty certain there was 8 digits, only the 1st digit was questionable.<br /><br />I did check out www.sparkplugs.com which recommend NGK BUHW-2. The good news is that is what is already in there and only a few months old too! The bad news is that I was hoping that incorrect spark plugs were the cause of my other motor problem (running rough after about 15min of full throttle) but that doesn't look like the case. I'll post a separate topic on it.<br /><br />cya soon<br />ff

 

[andrewkafp]

Re: What spark plugs for a 50hp Mercury?

Err yeah Aldo We did.. We came to live here.<br />1st job... Get a boat that fits the garage.<br />It's late May and it is been 23, 24 , 24, 25..<br />For my American friends.. That's Celsius.. <br />Terrible... so boring..<br />

 

[Dunaruna]

Re: What spark plugs for a 50hp Mercury?

I can understand why. My wife and I spent 4 days in Cal a few weeks ago, beautiful place, and the fishing!!!<br /><br />Aldo