1977 Evinrude 85 hp

[rockinrolla]

Recently I got a boat it's a 1983 skeeter ss-1 with a 1977 evinrude 85hp the motor cranks easy it idles great and runs great on top end good spark and compression but when I take off it does not want to plane out unless i have to stand towards the front of the boat I have looked over the motor and saw that number 3 and number 4 coils have a crack in them and at idle number 4 sometimes makes a ark but i've had the cowl off at night and could not see the ark could that be my problem? Sorry I'm new to boats this is my first one thank you

 

[boobie]

Re: 1977 Evinrude 85 hp

Coils will sometimes not break down unless under load as when under acceleration. How did you check your spark ??

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

with a spark tester it showed 1/2" gap on on all 4

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

with a spark tester it showed 1/2" gap on on all 4 and i also pull each of them off individually and listen to the motor the 4th spark did not change the sound of the motor and made an ark sound all of the other one's made a change in the way the engine sound but it is showing that spark is good on all 4

 

[McGR]

Re: 1977 Evinrude 85 hp

How is the trim angle on your motor? If it is trimmed out too far - that could be your problem. Bring the motor closer to the transom to keep the front end down during acceleration.

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

I don't have a jack plate but i have the motor trimmed all the way down when i take off and raise it up a little after it gets on plane I think the motor is where it needs to be as far as height because the anti ventilation plate is right above the water on top end Maybe the coils are breaking down on take off?? thanks

 

[emdsapmgr]

Re: 1977 Evinrude 85 hp

Sounds like you may have a bad coil. That 4th plug wire you pulled off should have made the engine rpm's go down. If it did not, that's a suspect cyl. You could have a coil going direct to ground-internally. Why not swap that coil with another-then run the engine and see of the problem moves to that other cyl. If it does-invest in a new coil.

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

okay will try that and see thanks for the help.

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

I tried that and swapped them 1,3 and 2,4 and still ran I changed all the plugs and noticed number 4 was cleaner than the other 3 but it still had a change in engine sound when i pull the plug off it had ngk plugs in it also I changed them with champion QL77JC4 gapped at 30

here are some photos of the old ngk plugs in order from 4,3,2,1 thanks for the help

 

[emdsapmgr]

Re: 1977 Evinrude 85 hp

It doesn't look like #4 is firing. If you shut the engine off after running-then pull the #4 plug is it wet or dry?

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

It doesn't look like #4 is firing. If you shut the engine off after running-then pull the #4 plug is it wet or dry?

It's wet but looks clean like the picture

 

[emdsapmgr]

Re: 1977 Evinrude 85 hp

Typically a wet plug is not firing.

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

okay thanks it's a wet so it must be a weak coil thanks for the help

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

update swapped around the coil wires no change spark is good rechecked with 7/16 gap strong blue ark on all 4, compression 115,115,125,115 I'm guessing more towards a low speed jet maybe? thanks

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

bump.

 

[BonairII]

Re: 1977 Evinrude 85 hp

I'd change all 4 coils if i were you. The 2 two that aren't cracked probably aren't too far behind. It'll give you peace of mind...and probably save you from lost time on the water when they do start to go bad.

 

[emdsapmgr]

Re: 1977 Evinrude 85 hp

When that engine idles, the carb butterflys should be closed in both carbs. Special idle passages in the carb body pass fuel into the engine. When these passages get a little dried fuel in them, they get restricted and can cause running issues-but only at idle. As soon as you crack the throttle even just a little, the carb will feed fuel from other jets. Often the engine may run fine at all rpm's except idle. You indicated that your engine runs fine at WOT. I doubt your take off problems are due to an idle jet, since the carb butterflys would be full open when taking off. If you've got a friend, he could help with a test. Take the cowling off, go boating. Take an inductive timing light with you. Put the timing light lead on each plugwire when the engine is under load. The flashes in the gun will show you the quality of spark on each cylinder and will show no fires, intermittents, and weak firing. Always possible you have a bad pack.

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

thanks, Will any brand do? or just get oem?

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

When that engine idles, the carb butterflys should be closed in both carbs. Special idle passages in the carb body pass fuel into the engine. When these passages get a little dried fuel in them, they get restricted and can cause running issues-but only at idle. As soon as you crack the throttle even just a little, the carb will feed fuel from other jets. Often the engine may run fine at all rpm's except idle. You indicated that your engine runs fine at WOT. I doubt your take off problems are due to an idle jet, since the carb butterflys would be full open when taking off. If you've got a friend, he could help with a test. Take the cowling off, go boating. Take an inductive timing light with you. Put the timing light lead on each plugwire when the engine is under load. The flashes in the gun will show you the quality of spark on each cylinder and will show no fires, intermittents, and weak firing. Always possible you have a bad pack.

okay will try this thank you for the help

 

[rockinrolla]

Re: 1977 Evinrude 85 hp

update I put the old ngk plugs back in it because with the champion ql77jc4 plugs it bogs a little when you give it a lil rev on the garden hose but with the ngk plugs it does not do it but the ark on that #4 coil arks again both plugs have the same .30 gap but why wouldn't it ark with the champion plugs it seemed like it ran better with the ngk plugs any help is appreciated