spark plugs

Basman7

Cadet
Joined
Aug 13, 2005
Messages
7
need to know best plugs and plug gap for 1979 evinrude 150 hp.dont have the power it should have
 

Goodoleboy

Chief Petty Officer
Joined
Nov 20, 2003
Messages
555
Re: spark plugs

Champions.....UL77v...gaped at .030<br /><br />Good luck!
 

steamboatwilly

Petty Officer 1st Class
Joined
Aug 7, 2005
Messages
248
Re: spark plugs

Hi Fishhawk7,,,I found some Stainless Champions,I think they are better than any of the other ones that Ive ever used.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: spark plugs

Well, the UL77V is a surface gap plug which cannot be changed. You can also use the (Q)L77JC4's. Those are gapped plugs.
 

jy118lfd

Chief Petty Officer
Joined
Jun 18, 2004
Messages
497
Re: spark plugs

I run the ql77jc4 in my 83 150 and they work great. More than 120 hrs this season mostly trolling at idle or 6 to 7 knots with about 10 to 25 miles of high rpm in and out and haven't fouled one yet
 

Goodoleboy

Chief Petty Officer
Joined
Nov 20, 2003
Messages
555
Re: spark plugs

I wonder why the seloc manual says UL77V plugs. Is that another mistake on their part?
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: spark plugs

That surface gap plug will work but, personally, I prefer the QL77JC4's in mine. They're cheaper and I never have had any trouble with them in any E/J motor I've ran. <br /><br />I was thinking about Jon's comment and got to thinking about one of the test motors which is a 150 crossflow. We tested some pistons and had to put 100 hours on them in a hurry. Then change them and send the "old" ones to engineering. I'm still using the same QL77JC4 plugs.
 

Goodoleboy

Chief Petty Officer
Joined
Nov 20, 2003
Messages
555
Re: spark plugs

I supose to that back in 79 that mite have been the plug the OEM recomended, and then from feild test Ql77JC4 prove to be better.<br /><br />Not a mistake for seloc to repeat OEM recomendation.
 

sixysixss

Recruit
Joined
May 23, 2005
Messages
5
Re: spark plugs

If I switch to the ql77jc4 in my 1984 GT150, what should they be gapped at, .030? I thought Johnson used the surface gap plug because of piston clearance issues. Am I wrong on that. It sounds like I can switch to a better plug, the ql77jc4, without a problem? Thanks.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: spark plugs

I run the (Q)L77JC4's in all my crossflows. If the piston hits, youve got other issues. Shouldnt be any problem.
 
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