1986 70 ETLJ yamaha "sprak plug problem"

[jammerz99]

Hi, I'm new to this site so would like to say hi to all.

I just bought a 1987 70 hp yamaha outboard 70ETLJ but for some reason it keeps blowing a sprk plug. Sometimes it runs for a couple of weeks without blowing one and other times it can blow 1 a day. Any help or suggestions??

Thanks,

 

[JUSTINTIME]

Re: 1987 70 ETLN yamaha sprak plug problem

Re: 1987 70 ETLN yamaha sprak plug problem

you mean fouling or blowing out the head

 

[jammerz99]

Re: 1987 70 ETLN yamaha sprak plug problem

Re: 1987 70 ETLN yamaha sprak plug problem

Hi, I mean the plug stops producing a spark, its dead, so I have to put a new spark plug the get the engine going again on 3 cylinders. This is an intermittent problem, sometimes I go over a week without changing a plug and sometimes I run only one day then one burns.

Thanks,

 

[JUSTINTIME]

Re: 1987 70 ETLN yamaha sprak plug problem

Re: 1987 70 ETLN yamaha sprak plug problem

i would ohm out the coils and check secondary resistance to plug

 

[jammerz99]

Re: 1987 70 ETLN yamaha sprak plug problem

Re: 1987 70 ETLN yamaha sprak plug problem

Hi, Thanks for the info. I will test the coils as per the service manual I have for the 70ETLN.

thanks

 

[BruceAML]

Re: 1987 70 ETLN yamaha sprak plug problem

Re: 1987 70 ETLN yamaha sprak plug problem

First, 70ETLN is a 1984 model motor. What spark plug are you using? What is the spark plug gap and did you torque the spark plug? The correct spark plug for your motor is a NGK-B8HS10. The gap is 1.0 mm or .039 in.

 

[jammerz99]

Re: 1987 70 ETLN yamaha sprak plug problem

Re: 1987 70 ETLN yamaha sprak plug problem

Hi, Sorry for giving you the wrong info. I just bought the boat and the service manual I got with it is a 70 ETLN, but after checking on the motor this morning I saw that I have a 70 ETLJ which is a 1986.

Sorry once again, I will check the plug, gap and torque.

Thanks, will keep you posted if you don't mind?