1969 Johnson 6hp issues

[CDN BEAVER]

Hello Ladies and Gentlemen,

Im currently trying to restore a 1969 Johnson 6hp outboard. Initially the motor would not start or run. I had determined that the cause was due to a stuck needle valve obstructing the flow of fuel to the carburetor. I also found that the fuel pump had obviuosly been taken apart at some point as afew of the springs and dome supports were missing. I replaced the fuel pump, and cleaned and inspected the carburetor until squeeky clean. The motor now starts, idles and seems to run fairly well in the barrel. I decided to mount the motor to the boat and try to take it for a good run.... Like I stated, the motor idles well, but in forward gear, it seems the motor will only run at about 1/4 to 1/3 of its potential speed.

I have removed the spark plugs and they are very black and sooty showing a very rich mixture. I suspect a poor or intermittent spark issue causing the low power. Am I on the right track here? I am in the process of removing the flywheel, but its turning out to be abit stubborn...

Finally I've noticed while running the motor in a barrel, that after the run, there is alot of black oil in the water. Where could this be comming from? I have changed the seals for the fill and drain plugs for the lower unit, and even if the leak were to come from here, I would not expect the oil to be black.

Any help, comments or suggestions are greatly appreciated. Thanks for your time.

Mark.

 

[Daviet]

Re: 1969 Johnson 6hp issues

How is the spark and compression?

 

[the machinist]

Re: 1969 Johnson 6hp issues

You may possibly have one cylinder not firing. These motors seem to run well on muffs or in a tank without being in gear, but when you put resistance on the prop, not a lot of power, (like 1/2). If this is the case with it running, pull one plug wire & then the other, this will soon tell if only one is firing. If so check all of your wiring connections, even the plug wire in the boot.

If one is not firing, then the reason you have a lot of unburned fuel on the water & plugs

Or a bad coil/condenser, points?

 

[CDN BEAVER]

Re: 1969 Johnson 6hp issues

Thank you for the quick replies.

A quick pull of the cord with the spark plugs removed and grounded does produce a spark, but in my opinion, not a very large/bright spark for both cylinders.

Im still trying to source a proper compression gauge, but as a general test, a pull of the cord with plugs installed is fairly stiff, and comparable, if not better to a similar 1972 model I have available.

I have not tried to run the motor with each of the leads removed 1 at a time. I will give it a try.

Im still struggling to remove the flywheel. I have the puller currently installed, and sprayed the shaft with abit of WD-40. I will let it sit overnight with some tension and hope it will pop in the morning.

Once the flywheel is off I can inspect the points and check for proper gap and static timing. While Im in there I will check the coils and capacitors for correct resistance and pico farad values.

Again, Im always open to any suggestions, and thanks again for your time. Its always appreciated.

Mark.

 

[Evinrude Boater]

Re: 1969 Johnson 6hp issues

Get yourself spark testers and run with them on the motor then you can see what's happening. The flywheel should come off with a good puller and lots of force. WD-40 won't help, it'll just get everything wet and oily. Put a long socket over the exposed crankshaft and heat up the flywheel somewhat to help expand it. The coils, points and condensors will cost you about $80 and well worth it. Chances are they're original and the coils are shorting out to the armature plate.

 

[Tim Frank]

Re: 1969 Johnson 6hp issues

A quick pull of the cord with the spark plugs removed and grounded does produce a spark, but in my opinion, not a very large/bright spark for both cylinders.

As suggested already, a proper purpose-built or purchased spark tester is the way to go.

Im still trying to source a proper compression gauge, but as a general test, a pull of the cord with plugs installed is fairly stiff, and comparable, if not better to a similar 1972 model I have available.

So that is about 15% more PSI than that other one...
NAPA must have an outlet up there....or Crappy Tire.

Im still struggling to remove the flywheel. I have the puller currently installed, and sprayed the shaft with abit of WD-40. I will let it sit overnight with some tension and hope it will pop in the morning.

A couple of careful taps on the end of the puller bolt usually helps. Make sure the bolt end is not in direct contact with the thread end on the crankshaft. Messing up that thread is an "ooooops" that most who make it never repeat, but if you pay attention to the warnings of those who have been BTDT, you may save yourself....too late for me...:facepalm:

Once the flywheel is off I can inspect the points and check for proper gap and static timing. While Im in there I will check the coils and capacitors for correct resistance and pico farad values.

IMO :The condensers are so comparatively inexpensive that if you have the flywheel off, change them ...just because. I had an intermittent ignition stutter on a 75 6HP that I could not solve....the condensers tested OK, but i finally changed them, as a last kick at it and the problem disappeared.
Have had a few other experiences with condensers in cars and small air-cooled engines that reinforces my "change it if you can touch it" view of condensers.

 

[kfa4303]

Re: 1969 Johnson 6hp issues

This should help walk you though a basic tune up.


http://www.duckworksmagazine.com/07/columns/max/index1.htm
http://forums.iboats.com/showthread.php?t=167352
http://forums.iboats.com/showthread.php?t=158086

 

[CDN BEAVER]

Re: 1969 Johnson 6hp issues

Thanks again to all for the help.

Still working on the compression tester...

I'd be interested to see what a "Spark Tester" looks like and how it works. Dont think Ive ever heard of it.

Finally got the flywheel removed. After letting it sit overnight with the puller installed, it popped off fairly easily.

I have tested the condensers and coils. The condensers are testing at 0.245 and 0.248 pico farads and are beyond serviceable limits. The limits I currently have are 0.18 - 0.22 pico farads. Can anybody confirm these values?
Also, Im looking for a resistance value to test the coils. Anybody?

 

[nwcove]

Re: 1969 Johnson 6hp issues

there is a good vid on youtube, search testing coils on a vintage outboard (or something like that), it is a good vid tho.

 

[kfa4303]

Re: 1969 Johnson 6hp issues

These may help.

http://www.youtube.com/watch?v=KT8rk5QWgS0

 

[CDN BEAVER]

Re: 1969 Johnson 6hp issues

Hello again...

So Im becomming alittle discouraged...

I have replaced the condensers, and adjusted the points to a gap of 0.020". The points were a nice frosted grey and had very little pitting. I reinstalled the flywheel, and tested for spark. With the leads conected to the plugs and grounded to the engine, I get a nice bright blue spark.


I put the motor back in the test tank and gave it a run... Its worse. It has a hard time idling, and I have very little speed when the engine is in gear. The plugs are black, and there is black oil in the test tank.

Im open to any further suggestions. Does this seem like like an ignition problem? Carb problem? Not sure where to go next with this guy. Im an aircraft maintenance engineer, but I feel like Im little in over my head. Wish I had proper manuals...

Again, I thank you for your time and all help is appreciated.

 

[hidef]

Re: 1969 Johnson 6hp issues

You most likely need to clean and rebuild the carb. Checkout the attached link for detailed instructions on working on the 6 hp. His other links are all very informative.

http://www.sschapterpsa.com/ramblings/OMC/OMC info.htm

If you want a service manual buy the OMC/BRP book. Do not buy one of the third party ones as they aren't very good.

 

[BonairII]

Re: 1969 Johnson 6hp issues

adjusted the points to a gap of 0.020". The points were a nice frosted grey and had very little pitting.

You should have replaced the points...they're fairly cheap.
I went thru some motor trouble recently and thought my points and condenser were ok. I replaced them and got instant improvement.

 

[kfa4303]

Re: 1969 Johnson 6hp issues

Hello again CDN. Here's a link that may help you get the carb dialed in.

http://forums.iboats.com/showthread.php?t=167352

While some oil in the test tank is normal if you're getting a large amount, then that means you're only running on one cylinder. While you may get a spark by grounding the plugs on the block, it may not in fact be strong enough. If you're confident in your coils, points and new condensers, then get some new spark plug wires. You'll be amazed what a difference they make. They're often over looked and crucial for delivering a sufficient spark to the plugs. Napa and Carquest usually sell 7mm copper core spark plug wire for about $3 a foot. 10-12 ft. is plenty for both cylinders. Get a couple of 90 degree crimp on connectors and boots and you're all set. Be sure to twist the new wires on to the coil posts rather than just poking them on too. Ultimately, you want the spark to jump a 1/4" gap. With the new condensers, (presumably) good points, new s'plugs and wires you have a virtually new ignition system, so that should no longer be an issue with the motor going forward. If it still runs funny, then you've got a fuel delivery issue. You probably just need to rebuild the carb. You can get a kit right here at iboats for about $20. Give these tricks a try and let us know what you find.

 

[RandyJ]

Re: 1969 Johnson 6hp issues

I just finished posting on my thread about a very similar problem... 1972 Johnson 25 hp brought back from the dead.. (or something like that). I improvised a spark checker by taking a clean spark plug and bending the tip back to give me near 1/4". Just holding the base to the block for a ground I was able to tell a huge difference between the fire on top and bottom cylinders. It pretty much set me straight on where the problem was... in the ignition. I'd say that most likely, you're gonna have to clean and set the points and replace condensers. My experience with old small engines & outboards is that the condensers go bad while sitting up for years... not to mention the oxidation that develops on the point surfaces. A light cleaning of the points works wonders some times... but a simple tune up kit makes it even better.
ALSO, I'm far out in the boonies and everything is a very long ways off. So, I do improvise A LOT. To clean spark plugs since I don't have a sand blaster type plug cleaner or a ready source for new plugs I put them in a drill and drill them down into a bucket of sand... then blow them clean... been working pretty good!

 

[Gwichers]

Re: 1969 Johnson 6hp issues

Hi i resored a 62 Johnson 3hp awhile back. Had the same symtoms lack of power and lots of oil film on top of the water. Turned out to be the timeing. Im going to suggest you do an ignition tune up as explained in an article from www.outboard-boat-motor-repair.com. Or at least check your timeing as explained in the same article with a ohm meter and if that doesnt work then do the tune up. P.S. It also explains how to test coils, has all the part numbers and worked awsome for my 3hp

 

[freddyray21]

Re: 1969 Johnson 6hp issues

You should have replaced the points...they're fairly cheap.
I went thru some motor trouble recently and thought my points and condenser were ok. I replaced them and got instant improvement.

while points do go bad it is a rare occurrence. Make sure they are shiny clean. It sounds though as if you have good spark so carb overhaul is in order. On a motor sitting that long the carb will need an overhaul.

 

[CDN BEAVER]

Re: 1969 Johnson 6hp issues

Thanks to all for the hep. It is truly appreciated. I will be sure to keep you all posted...

 

[boatlemmy]

Re: 1969 Johnson 6hp issues

I had a similar problem with my 60 v4 . black in the runtank and running rich. the black is exhaust and unspent fuel from running too rich. my problem turned out to be the cork float in my carb. modern fuel had ate the shellec off of it and it was sinking causing to much fuel to enter the bowl. not sure if your year would still be cork but you could have a worn needle on the float. good luck