1977 140HP can I run this plug QL77JC4

[RR24]

1977 Johnson 140HP can I run the QL77JC4 or do i have to run the UL77V?
I read that the QL77JC4 was a better plug to run becasue it has a true heat range, but was wondering if it would have a clearance problem.

 

[boobie]

Re: 1977 140HP can I run this plug QL77JC4

The chart says 1973-1984 140 hp require UL77V or L16v. Your right, with any other plug for those years you could have a clearance problem. I perfer the L16V as they are hotter and I've had good luck with them.

 

[Dhadley]

Re: 1977 140HP can I run this plug QL77JC4

The (Q)L77JC4 plugs are the prefered plug in that motor with todays fuel. You don't need any higher combustion temps with what we have for fuel these days.

 

[Vic.S]

Re: 1977 140HP can I run this plug QL77JC4

I note though that the parts catalog indicates that L77J4 could be used for sustained low speed operation.

On that basis it should be possible to use L77JC4 (or QL77JC4) without any clearance problems

 

[Vic.S]

Re: 1977 140HP can I run this plug QL77JC4

I note that the parts catalog indicates that L77J4 could be used for sustained low speed operation.

On that basis it should be possible to use L77JC4 (or QL77JC4) without any clearance problems

 

[RR24]

Re: 1977 140HP can I run this plug QL77JC4

Thanks for the info folks