Need plug gap on 1980 Evinrude 25 hp?

[River Trapper]

Any sugjestions on plugs would be appreciated as well as where I could find a manual for this motor haven't been able to find anything local. Thanks!

 

[bubbakat]

Re: Need plug gap on 1980 Evinrude 25 hp?

QL77JC4 OR L78V OR QL82C Gap at 30<br /><br />Champion plugs

 

[rickdb1boat]

Re: Need plug gap on 1980 Evinrude 25 hp?

I would use Champion QL77JC4, gapped at .030. Factory Manual(Well worth it) can be ordered at the link below:<br /><br /> web page

 

[River Trapper]

Re: Need plug gap on 1980 Evinrude 25 hp?

Bubbakat, I was pretty sure it was 30 but wanted to double check. Here's what I found for champion plugs L77JC4 is this the same as the QL77JC4 reason I ask is the motor wants to backfire now after putting in these plugs with the correct gap but if I put the old plugs back in no backfire or is there something else going on here? Thanks for the fast reply to my post much appreciated.

 

[walleyehed]

Re: Need plug gap on 1980 Evinrude 25 hp?

.030 will work fine unless you do alot of trolling or idling around. .035-.040 is better suited in the case of lower rpm use.

 

[bubbakat]

Re: Need plug gap on 1980 Evinrude 25 hp?

walleyed is right on for this and you can find these plugs at wal-mart for around 1.89 each made by champion

 

[rickdb1boat]

Re: Need plug gap on 1980 Evinrude 25 hp?

QL77JC4 is the same plug, except it is a resistor plug(Q). Same heat range. Gap at .040 as suggested and it should solve you problem. Your old plugs probably had a wider gap. If you still have them, check and see what they were gapped at. My 70 HP rude runs better at .040.

 

[G DANE]

Re: Need plug gap on 1980 Evinrude 25 hp?

Hi River Trapper<br /><br />If it backfires, you probably have too lean iddle mixture ( try to turn iddle mixture screw 1/8 turn out ) or your sync´n linck it not properly adjusted. Check to see if the trottle opens before the ignition cam roller reaches center of the two small timing marks on stator plate, above carb.<br /><br />It will always backfire easyer on muffs, cause of no backpressure. <br />When back in water do the procedure of adjusting iddle mixture, with boat mooving freely in forward gear. Remember to warm motor up first.