Surface gap spark plugs

[SearchMaster]

I have an old pontoon boat ('92 IIRC, 90HP Mariner 3-cyl) that is running a bit rough so I was going to try to do some tuneup work including changing the plugs. I have changed spark plugs on a few different engines successfully so it seemed like a simple place to start (and the originals are 15 years old now). I haven't pulled the plugs from the boat yet but I looked at what was there without pulling them and they were NGK BUHW-2's, so I ordered replacements.

When they came in, I admit I thought they were defective because the electrode was missing I hadn't ever seen a surface gap plug, so I started Googling. As I understand it from reading, surface gap plugs require a higher voltage so I was curious if I could use them (assuming what I pull out are the traditional plugs) or not? Obviously if I pull them and the existing plugs are surface gap, then the question is moot.

 

[Zenmervolt]

Originally posted by: SearchMaster
I have an old pontoon boat ('92 IIRC, 90HP Mariner 3-cyl) that is running a bit rough so I was going to try to do some tuneup work including changing the plugs. I have changed spark plugs on a few different engines successfully so it seemed like a simple place to start (and the originals are 15 years old now). I haven't pulled the plugs from the boat yet but I looked at what was there without pulling them and they were NGK BUHW-2's, so I ordered replacements.

When they came in, I admit I thought they were defective because the electrode was missing I hadn't ever seen a surface gap plug, so I started Googling. As I understand it from reading, surface gap plugs require a higher voltage so I was curious if I could use them (assuming what I pull out are the traditional plugs) or not? Obviously if I pull them and the existing plugs are surface gap, then the question is moot.

If both plugs are the same code, then they are the same entirely. If the plugs in the engine now are marked BUHW-2 and the surface gap plugs you just bought are also BUHW-2, then they are identical to the plugs in the engine.

A part number wouldn't mean much on spark plugs if it didn't also specify the tip type.

ZV

 

[todpod]

Most Outboard engines ran surface gap plugs, A few of the smaller engines such as Honda ran regular plugs, Not sure about now I haven't worked on these for a long time so it may have changed. I am pretty sure you will pull the old plugs out they will be surface gap.

 

[SearchMaster]

You're probably right, I guess I thought it was a fairly new concept and an old boat.