No manual, help with spark plug purchase

[MKEPontoon]

Hello,
I bought a pontoon that is equipped with a 1996 Mercury 40ELPTO 2-stroke 4 cylinder motor. lately, I've been having issue with starting after warm up. I can start at the launch but once I get to my spot and turn off the motor, it takes like 30 mins of trying to get it started again. I've been researching and it could be a lot of thing. So I decided to start with the simple things first. I installed the plugs (NGK BP8H-N-10) according to a manual I found online but after reading it, it's for a 40hp 3 cylinder ELPTO motor. The motor did start really quick, better than before. Now I'm second guessing if it's the right spark plug. Do anyone have a manual or could tell me which plugs do my motor take?

 

[Chris1956]

Gee, Spark plug application data is avail at many spark plug web sites.

A lot of Mercs take a surface gap plug like BU8H. You might check with NGK.

 

[MKEPontoon]

Thanks for you help but I did look at multiple sites. I get NGK BUZHW-2 and NGK BP8H-N-10. Just wanted to make sure I bought the correct one.

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[racerone]

Hurry----Read your manual.---Even call Mercury.-----Talk to a shop.----Find out why you are having difficulty starting this motor.

 

[MKEPontoon]

Hurry----Read your manual.---Even call Mercury.-----Talk to a shop.----Find out why you are having difficulty starting this motor.

Thanks for being so helpful! I really appreciate you help.

 

[racerone]

Ok----Start with the correct sparkplugs then.------In my opinion there should be no reason for a motor to be hard to start when warm still.-----I see more and more folks who know how to work a smart phone and are challenged by the operation / starting of an outboard motor.-----Last summer I had to coach one individual word for word on how to start his motor.----He had no trouble with his phone and all the options on it !!

 

[MKEPontoon]

If I have a manual, I wouldn't be asking what kind of spark plugs to use. Also you are correct, the motor shouldn't be hard to start after warm up, it should be the other way around but in this case, this is the issue. I've own multiple boats before this so starting a the boat is not the issue here.

 

[Alumarine]

What's the serial number of the motor?

 

[MKEPontoon]

I have it at storage. I'll stop by and get the serial numbers.

 

[MKEPontoon]

What's the serial number of the motor?

0G345302

 

[Alumarine]

BUHW-2 or if you want tungsten BUZHW I believe.

 

[MKEPontoon]

BUHW-2 or if you want tungsten BUZHW I believe.

Thanks... appreciate your help!