Logo
FULL SITE MENU

1969 Evinrude 85 Floods at Idle After Warmed Up

S

SteveInMN

Member
1969 Evinrude 85.
Starts from cold a little slow.
Runs rough at low (idle level) speed. Coming into dock, often dies and when it does it WILL NOT restart. I never turn it off out on the water because it WILL NOT restart. Pull the plugs, dry them, let the cylinders air, reassemble and it starts, so I am assuming (Ha!) it is loading up and flooding.
Runs at mid to high speed like a champ.

FUEL
I have cleaned the carbs several times in my ultrasonic tank, installed new OEM kits. Floats are set perpendicular to carb body. New OEM fuel pump. New fuel line. Fuel/water separator installed. I only run non-ethanol gas, 1 oz /gallon Seafoam, Pennzoil Marine @ 50:1. I set the four low speed needle valve screws as best I could with the engine in a tank in the backyard. No problem with restarts in that environment (“BOOM”, she’s UP!) , but of course the engine is idling, not working hard and not all that hot.

IGNITION
Spark gaps a little over 1/4″ all cylinders — seems short, but a respected poster commented this is normal for these engines. NOS Wabash amplifier,new coil, new points set to .01″. Battery @ 12.6V.

Compression @ 105 pounds all four cylinders.

I would throw this on the scrap heap, except is is cosmetically excellent, the electric shift lower works great, it runs well at speed, and it is original to the the Crestliner Dane hull/Spartan trailer package from 1969.
Any ideas?
Thanks,
Steve
 
Well----Spark on a" good " ignition system can jump 1/2" and yes HALF INCH.----Need to look into that.----What is the setting on the low speed mixture needles.---Your compression is a little low , so try another gauge.
 
Thanks for getting back!

Spark on a" good " ignition system can jump 1/2" and yes HALF INCH.----Need to look into that.

-- Agreed, seems short. I'm going off this old thread stating anything over 1/4" is 'normal' for this engine (1969 V4) -
I'm in no position to question Mr. Reeves. Of course -- more spark is always better. The gap jump is consistent from plug to plug, so I am supposing the wires and caps are all good (or all equally bad?). The amp and coil and points are new or NOS. The cap and rotor are clean and there were no visual problems.


What is the setting on the low speed mixture needles.

--I am assuming you mean turns out from closed. As I face the carbs:

1 - 7/8 2 - 3/8

3 - 1/2 4 - 3/4


Your compression is a little low , so try another gauge.

--Agreed. I am a little older than the engine, mine is running low too. Yes, I did cross-check the gauge, it is spot-on. In your opinion, could compression on the lower end of acceptable cause flooding only when warm idling?
 
Throttle position does NOT matter on that 2 stroke model.----Initial setting is 5/8th turn out on the mixture screws.-----Good spark can jump a gap of 1/2" on those.----Up to you to investigate.----I can not touch your motor!
 
Does choke come on part way when you turn key to " on "?----Does choke close fully when you operate the choke switch ?----Does choke come OFF when motor warms?----Thermostat in place and working properly ?-----Or perhaps choke was modified.----Remember I can not see / touch your motor.
 
Throttle position does NOT matter on that 2 stroke model.

-- Good to know!

Does choke come on part way when you turn key to " on "?
----Yes!

Does choke close fully when you operate the choke switch ?
----Again - yes !

Does choke come OFF when motor warms?
----Good thought! I will verify this.

Thermostat in place and working properly ?
----Vernatherm is in place and the throw is 1/4" @ 175 Deg.. No spitting when the motor is cold, does start spitting once warmed up.

Or perhaps choke was modified.
---I see no evidence of that.

Thanks,
Steve
 
OK, got it 95% sorted.

It turned out to be the distributor cap -- or the rotor -- or the plug wires -- or the DEAD SHORT in the hot wire connecting the two points sets (!!!)

Now it idles without dying and, most critically, it RESTARTS.

So now through long, slow channels, the warm motor's idle gets VERY lumpy, and when you go to hit the throttle, one or more cylinders definitely kick on-off-on-off till the flooded cylinder(s) clear. Which seems like rich loading to me.

To address that, I intend to 'try' to adjust the low speed screws. They did not seem to have much effect in past efforts till the screw was almost closed, at which point the engine just quit (or wanted to quit). Sort of like elevator buttons that aren't connected to anything. But that was before the ignition improvements, so I'll try again.

Joe Reeve also mentioned that these engines never did idle all that well, and that the partial solution "back-in-the-day" was to replace the surface fire plugs with conventional J hook plugs gapped @ 0.030". I will give that a go as well.

Open to other Brilliant Suggestions!!
 
Back
Top