6 HP Evinrude outboard won't start, 60 psi low Compression?

[Ranger118]

Hi all,

A friend has asked me to look at his 6hp 2 stroke which won't start.
This motor running good last year, but just won't start now after a few months storage.

Model: 6803C
Spark: ok
Compression seems low only 60 psi on both cylinders.
What should the compression be?

 

[eavega]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

Compression can vary depending on technique, the tool used, etc. As long as it is not 0, and the two cylinders are within 5% of each other, then you should be good to go. I had an old 10 HP Johnson that read 65 psi on both cylinders, and she would start on the second pull. Look elsewhere for your starting problem. Spark: ok means what? Did you use a spark tester and verify it would jump a 7/16" air gap? Are your plugs correctly gapped? Try spraying premixed fuel into the carb and try to start. If it catches for a moment, then your problem could be fuel. You might need a good carb cleaning if you ran unstabilized fuel through the motor and put it away.

Rgds

 

[kbait]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

60 psi on those spindle recoils is fine as you can't pull very fast at all w/that setup. Agree w/eavega.. check spark QUALITY, not just if it sparks across the .030" gap in open air.. you need more than 1/4" in open air to ensure spark over the plug gap under compression. And a bit of premix in the carb throat or plug holes will tell you if it's actually firing after a successful spark test. If it's firing, look to fuel delivery/watery fuel. Good luck!

 

[bullcity101]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

bad fuel has been an issue for me in the past, caused some serious headaches checking everything over just to find out I had a little water in the fuel, season to season fuel just doesn't really cut it.

 

[raczekp1]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

two days ago i had the same motor, 60 on both cylinders.
pistons took out and upper piston was scored and head warped

 

[Ranger118]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

After pull from the fly wheel few times, the motor starts to run.
But it runs roughly and won't stay on idle.

Checked the fuel pump, it seems a small spring is missed.
There should have 2 springs in side the pump, but only 1 in it.




Can anybody know where to buy this small spring and the little plastic thing?

Thanks for all your helps!

 

[AlTn]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

try sierra fuel pump kit #18-7823..iboats has them and napa may as well

 

[Ranger118]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

try sierra fuel pump kit #18-7823..iboats has them and napa may as well

Replaced fuel pump. no change.

 

[AlTn]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

spark and carb are next up

 

[the machinist]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

I agree with kbait. Your motor is a 1968 so it uses a magneto ignition, (points & condenser) air gap to check spark on these old motors is 1/4", they won't jump the 7/16" like the electronic ignition. Points are have a commonality to become slightly oxidized when setting, so dragging a point file thru them may help. Also you may consider checking the spark plug wiring, especially at the plug boot connection. The metal coil inside the rubber boot that goes over the spark plug end is just poked into the plug wire. You can just pull the boot off, cut off 3/8" of wire & reassemble for possible better connection there.

 

[Ranger118]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

When pull the flywheel with a rope directly, the motor starts at WOT, but it stalls when turning to lower rpm. no idle at all.

Any help is much appreciated-Thanks

 

[jay_merrill]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

Sixty psi on that motor is fine and is probably average for it. I have had several of them and that's about what I used get on them consistently. Remember that you are pulling the motor through with a rope start, not a continuously operating starter.

There are quite a few things that could be causing your problem - bad fuel, bad spark, points that need adjustment, gummed up carb, etc. The good news is that the motor is very simple and working your way through the trouble shooting process is pretty easy. Since your friend is getting the motor ready for a new season, I recommend going through all of the usual items for annual maintenance. This might include a carb rebuild,water pump, new plugs, new plug wires if needed, etc.

With that motor, its either spark or fuel - check them both out, step by step.

 

[Ranger118]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

Update:
Fuel tank, fuel line, and fuel are in good condition. We have another 8922D, which works very well, uses the same fuel stuffs.
Re-checked the 2 points, sanded, cleaned and re-set the gap to 0.020.
The motor still hard to start, and if it starts, it runs 3 - 5 seconds and die.

The motor is pretty dirty inside, will this make the reed valve dirty too?

 

[nwcove]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

still dont see any mention of a carb soak/cleaning and re-kit? ( welch plug out for the idle circuit!!) ?

 

[Ranger118]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

still dont see any mention of a carb soak/cleaning and re-kit? ( welch plug out for the idle circuit!!) ?

Have fully checked / cleaned / re-built the carb today, even the welch plug was replaced.
Still no change :facepalm:

 

[SeaKaye12]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

Ranger; I see that you have cleaned and re-cleaned the points etc...but nowhere do I see in your posts that you have verified adequate spark. 1/4" Bright sorta blue spark????? Yes or no????

Simply observing a tiny spark across the plug in open air is not enough. You may indeed have verified this...but you do not say so one way or another.

All your work on the fuel system has resulted in no change; it's looking like ignition to me. Are the coils showing cracks? How are the wires? Sometimes if I am not replacing them I will snip a litttle bit off each end to freshen up the connection a bit.

We can sense your frustration; it's just a simple machine....don't let it get the better of you

Chuck

 

[Haffiman]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

With closed choke and pulling the starter multiple times, fuel should flow out of the carb throat. Of not, most likely a crank case compression problem. Might be reed valves, might be crank shaft seals (upper and lower), might even be leakage between crank-cylinders.
That it starts and runs shortly when pulling directly on the fly-wheel, indicates bot spark and fuel are there, but not enough under-pressure to suck it in.

 

[Ranger118]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

With closed choke and pulling the starter multiple times, fuel should flow out of the carb throat. Of not, most likely a crank case compression problem. Might be reed valves, might be crank shaft seals (upper and lower), might even be leakage between crank-cylinders.
That it starts and runs shortly when pulling directly on the fly-wheel, indicates bot spark and fuel are there, but not enough under-pressure to suck it in.

Yes, exactly!
With closed choke and pulling the starter multiple times, fuel flows out of the carb throat.

I will open the power-head to see if anything wrong inside.

 

[SeaKaye12]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

But Ranger....

What Haffiman is saying (or at least what I understand him to be saying) is that if fuel was **NOT** flowing out of the carb after closing the choke and pulling it over multiple times....**THAT** would indicate crankcase compression problems.

You are saying that fuel **IS** flowing. It is the crankcase compression (suction) that is sucking the gas out of the bowl.

Plus; you had a running engine last year...with nothing but storage in between.

Something is not making sense here.

I wouldn't go pulling the block apart quite yet.

Chuck

 

[Haffiman]

Re: 6 HP Evinrude outboard won't start, 60 psi low Compression?

Time to be a bit 'naughty' in testing.
Got a variable speed power drill?

Put the lower unit in a bucket of water not to ruin the impeller.
Hook up a spark tester to both plug leads, about 1/4+ in gap.
Get a socket that fits the flywheel nut, grind off the shaft of an extension and put into the power drill.
Start with the drill at lowest RPM and slowly increase the speed and at the same time monitor the sparks.
If sparks starts turning from bluish(high speed) to yellowish(low speed), that is when you are loosing ignition, if that is your problem.
If spark stays bluish all the way down in RPM, ignition is most likely NOT the problem.