spark plug gap

R

RRRKKK

Cadet
Joined
Dec 6, 2003
Messages
24
Is there any advantage to increasing the gap from the recommended .030 to .040 I have a 1991 3cyl 60 hp Johnson with a new powerhead on it. I plan on using the Pennzoil blended oil after it gets broken in.
 
D

Dhadley

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

Which spark plugs are you using? Whats your target top rpm with an average load?<br /><br />Why wait until after the break-in to start with the Penn blend?
 
R

RRRKKK

Cadet
Joined
Dec 6, 2003
Messages
24
Re: spark plug gap

I am using the champion qy77jc4 I think that the number anyway its the stock oem plug And I have 2 6gal tanks premixed at 24/1 with oem oil, as I did this at dealer who rebuilt power head I only had it in water a short time to see how it ran (cold here in IL) river is frozen now with a normal load it ran 5900 RPM at WOT I was checking as I have a 13 1/4 15 prop on it and was wondering about a 17 pitch prop I also will need to check motor height as I read on this board that the motor cavatitation plate need to be even with the bottom of the boat
 
rickdb1boat

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: spark plug gap

I run my 91' 70 HP Rude Motor at .040. It idles better and runs better at lower speeds at that setting and no plug fouling. And I do troll alot of the time, also. I have always run my OMC motors at .040, including my 89' 28 HP Johnson. Both Still goin' strong, too. You will probably not notice any top end gain from this. 5900 RPM's is right where you want to be. I wouldn't change the prop if I were you if the motor height is correct.
 
D

Dhadley

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

Agreed. Right plugs, right rpm's, .040 gap at those rpm's. Don't change the prop.<br /><br />Why did it have to be rebuilt?
 
R

RRRKKK

Cadet
Joined
Dec 6, 2003
Messages
24
Re: spark plug gap

I bought it off E-bay with a scored lower cylinder (gas smelled like varnish)I was going to overhaul it but my dealer did it for the right price I put a new water pump on it as well as carb overhaul and rewired it from tiller to remote also took off VRO and replaced with new fuel pump hole shot is amazing about 3 seconds to plane it has a hydrofoil on it I was going to take it off but now don't think I will its on a 17' Lowe roughneck (replacing 30HP)I wish I had read about motor location when I put it on boat. I use it mainly in the Mississippi river can't wait for ice to leave!!!
 
D

Dhadley

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

I would not change a thing for now. Get the motor past the break-in period and get used to the handling traits. Go have fun. We have all summer to experiment with things. <br /><br />Good luck!
 
You must log in or register to reply here.
Top