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71 Johnson Hydro Electric running too rich

michellebedore

New member
It's a 100 hp...The motor is still running super-duper rich...brand new champion marine spark plugs totally wet with oily gas with the choke open.

Is that normal????? Can this be remedied with "low idle jet" adjustment?
How do you arrive at the *proper* low idle speed, when no adjustment makes any difference?
Speaking of idling,

The RPMs seem too high (to me) but we don't have a tach hooked up...even though there IS a tach....no wires coming from the tach under the dash, and nowhere obvious to hook it up at the motor. My husband has a dwell meter, (and a timimg light) but it's for cars, but he's afraid to hook it up to the outboard for fear of frying something....anyone know about the use of a car dwell meter for outboards? And where is the coil you'd hook it up to???


So we're scratching out heads...I'm reading online and trying to garner more insight and info.

Quick recap:

*Fuel pump working fine
*Newly rebuilt carbs
*Fuel lines all clear
*Correct fuel mix
*Throttle linkage and choke linkage synchronized
* Low Idle needle turned 7/8th turn
*2-phase choke solenoid bypassed/disconnected, so we know THAT'S not the problem. (we diconnected it because we blew about 10 main line fuses in one day at a lake, and were informed of the choke solenoids in those often causing that problem.

We are wondering if the leaves inside the intake manifold could be all gummed up...after all, we DID run old gas in it which gummed up the carbs and caused a needle float to jam....which is why Nick ended up rebuilding the carbs and putting in new needle floats/seats last month. The floats we installed properly.

It has been running too rich ever since--and was even before the carbs were rebuilt. If we try to slow the idle down, the engine dies.

And yes, we now know outboard gas cannot be used if it's been sitting more than a few months--unless it has that outboard fuel stabilizing additive. We have it in the new gas right now, but in the amount directed for "operational use".

Here's a link to a quick video of it running today.

http://www.youtube.com/watch?v=pNAQX95jumg
 
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Check the spark...got to have a strong blue spark. Mr. Joe Reeves has a thread on here about how to make a spark tester and the procedure to use it.
 
Thermostats installed and working properly?
What are the compression readings?
Will the spark jump 7/16" and is bright blue?
 
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Thermostats installed and working properly?
What are the compression readings?
Will the spark jump 7/16" and is bright blue?

I will have Nick do a compression reading and let you know what they readings are.
I don't know about the thermostats or the sparks, but I will relay this to Nick when he gets home from work. I'm sure he's checked...or I hope he has!

Thanks for the suggestions! :)
 
My husband did a compression check after work last night. The compression readings are:
#1 120
#2 120
#3 118
#4 117-118
We don't own a spark checker yet. Our manual calls for a needle-type spark checker. As far as the thermostats go, we haven't checked it out since we haven't had any overheating issues. I understand it could be running too cold though. I read up in our service manual how to check it by submerging it in hot oil, and how to check to see if the hot horn is working as well.
There is a thermostat inside the choke solenoid circuit, but that was disconnected after it was suspected as the culprit for our problem.
So we will be shopping for those temp. crayons and a needle-type spark checker as the manual calls for. BTW, The manual calls for 100 degree and 130 degree temp. crayons too, and the ones I've seen online were for higher values.....must be because it's that vintage, huh?
We have the Seloc Service manual, but I was fortunate enough to very recently purchase a mint condition Johnson service manual for our exact outboard. It has helped us quite a bit, especially being so new to boating and outboards. Our boat is a very pretty little vintage runabout; a 1964 Glasspar Avalon powered by a 1971 Johnson 100 HP hydro-electric outboard.
We are fond of it, and prefer to learn to work on it ourselves rather than be completely ignorant of how it should operate and troubleshooting.
Again, we feel grateful to everyone on these forums for giving their time & help...espectially having the patience and willingness to help the very "new" do-it-yourselfers! :D
 
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