Johnson 4hp 1982(ish) no spark

[bobjob]

Hi, I have recently bought a very clean but old 4hp Johnson outboard model J4BRCNR which I think means it is a Euro rope start (BR) built in 1982 (CN). Not sure what the "R" at the end is though.

When I first got it in October last year it fired up but wouldn't tick over or run very well at all, I put it down to old fuel, cobwebs, etc and put it away till the weather got better. The point is it definatley fired.

Got it out yesterday, put new fuel and pulled the starter rope and nothing, tried easy start sprayed directly through carb venturi....nothing, this would normally at least get a pop or some kind of fire/combustion providing there is a spark.

So... Took the plugs out, they look healthy enough, tried shorting to the power head and pulled starter rope, no spark.

I made sure the "STOP-START-RUN-THROTTLE" lever was not in the "STOP" position. I have read online that you should disconnect the shut off switch but cant see how that is possible (not easily anyway).

I have now removed the flywheel and nearly threw up when I saw what lay beneath.....

POINTS!!!!! CONDENSORS!!!!!2 SETS OF EACH!!!!

I haven't seen points for at least 20 years since I owned an 69' Mini Cooper and that had 1 set not 2, and from what I remember they were the most complicated and unreliable piece of junk I ever came across, in my view cars went from being unreliable antiques to modern trusty steeds when they went over to electronic or CDI, it really was a huge leap in their technology IMO.

Anyway to the point, how do I tell if they are working or not? I have noticed that one of the condensors has been changed as it is brand new, is it a case of "Process of elimination"? Should I change everything one by one?

Big question...Can I change the system to CDI? I have read that some of the later models were equipped with it.

Any help would be greatly appreciated, many thanks BOB

 

[nwcove]

Re: Johnson 4hp 1982(ish) no spark

Well, im my opinionyour points and coils are every bit as good as any electronic ignition!! You may just need to clean the points on your motor as they do need attention every 20 years or so. Dip a buisiness card in acetone and pull it through each set of points. Condensors rarely fail, and for both to be gone would be very rare. Your coils are the modern type, and they rarely fail also . Make sure to torque the flywheel to spec or you will sheer the key for sure.

 

[Rick.]

Re: Johnson 4hp 1982(ish) no spark

I'm surprised too. My 1980 4 hp has CDI. Still I agree there is nothing wrong at all with points motors. Follow mwcove's advice and get yourself a spark gap checker as well. Then you can set it for 1/4 inch and see if your spark is good enough to jump it. Spark should be blue/white and snappy. Set points to .020. Best of luck. Rick.

 

[bobjob]

Re: Johnson 4hp 1982(ish) no spark

Thanks Capn', I have heard many times how the old mechanical systems are best but I just don't see it, every vehicle I ever owned with points used to give me issues and since CDI no problems, same with injection, everyone says how good carbs were but I have owned 2 Yamaha R1's early one with carbs and later one with injection, no competition when it comes to starting on cold mornings I can tell you!

But thanks for advice, I will try cleaning points tomorrow, I really hope it is just a build up of dirt, can I spray WD40 or similar to clean up?

Is Acetone alcohol? I'm from Uk and I'm not familiar with this although I have heard of it, maybe we have a different name for it? I'm on this forum because there seems to be more knowledge for these engines than in UK.

 

[bobjob]

Re: Johnson 4hp 1982(ish) no spark

I'm surprised too. My 1980 4 hp has CDI. Still I agree there is nothing wrong at all with points motors. Follow mwcove's advice and get yourself a spark gap checker as well. Then you can set it for 1/4 inch and see if your spark is good enough to jump it. Spark should be blue/white and snappy. Set points to .020. Best of luck. Rick.

Maybe I've misread the dating sheet, couldn't really make the letters fit any other year, unless its a 1924!!!!! Hope not.

 

[TN-25]

Re: Johnson 4hp 1982(ish) no spark

Although an old points-type ignition will gradually wear due to the light contact and arcing, they are also cheaply and easily serviced. Not a bad deal. I don't know about the Belgian motors, but in North America the 4-horse and many other remaining points-type motors were switched over to CDI on the 1977 models. Also the integral gas tank we got in North America for 1979 was the same one the Belgian motors started using in 1972.

 

[bobjob]

Re: Johnson 4hp 1982(ish) no spark

Although an old points-type ignition will gradually wear due to the light contact and arcing, they are also cheaply and easily serviced. Not a bad deal. I don't know about the Belgian motors, but in North America the 4-horse and many other remaining points-type motors were switched over to CDI on the 1977 models. Also the integral gas tank we got in North America for 1979 was the same one the Belgian motors started using in 1972.

Hmmm....getting worried now, maybe I've bought a mixnmatch of old bits.

Anyone heard of points-to-cdi exchange? How is the CDI system mounted? Is it similar to the points system in fitment? ie; back plate mounted under flywheel with a pair of pickups wired to coil packs and a control module of some sort?...

I guess as long as they are 180 degress apart (the pickup's) in the same position as the points pickups the timing would be ok? I'm thinking of a 2 stroke moped I own and that is very simple but it does only have 1 cylinder.

I know this acute parranoia of points seems irrational but I just like trying to update things, bad habit I know. Had a MK1 1969 Austin Mini van once and fitted a 2007 Honda Vtec 160bhp engine and it just felt right

 

[Rick.]

Re: Johnson 4hp 1982(ish) no spark

BRP -- Parts Catalogs

Relax. Your motor had points from the get go. Lacquer thinner will clean them as well as acetone.
Rick.
Edit. I would not recommend spraying wd40.

 

[colbyt]

Re: Johnson 4hp 1982(ish) no spark

Is Acetone alcohol? I'm from Uk and I'm not familiar with this although I have heard of it, maybe we have a different name for it? I'm on this forum because there seems to be more knowledge for these engines than in UK.

No! It is a really nasty chemical that causes cancer in California.

 

[bobjob]

Re: Johnson 4hp 1982(ish) no spark

so maybe any solvent based cleaner then? Anyone know about dwell settings? Got new plugs coming tomorrow, fingers crossed i'll see some life then.

 

[colbyt]

Re: Johnson 4hp 1982(ish) no spark

All you need to do is make them shiny again. 50 years ago we used and emery board or some 400 grits sandpaper. Now everyone wants to use chemicals.

I'm am suspecting your coils, especially if the are the original but test before you roll out the parts cannon.

 

[bobjob]

Re: Johnson 4hp 1982(ish) no spark

Thanks Colbyt, I have also used emery board in the past but was wondering if that was a mistake (maybe why I never got on with points ignition systems) but will have a gentle clean up when I get the plugs fitted.

Any idea what the coils should be outputting?

I used to change the condensor on my mini about once every 4-6 months, probably due to ridiculous postioning of the distributor (right in the middle of the front grill, exposed to elements until I made a cover from an old tray) and I have noticed that one of the two condensors fitted on this motor is brand new, no doubt about it, so maybe previous owner also had some difficulties getting it to run right....

This is why I don't like points, if you have CDI with a problem you just change the plug....still no good?...change the CDI unit, hey presto. I have never had a problem develop into more than this in the last 20 or so years of owning a vast collection of cars, bikes, karts, lawnmowers, etc. Just never had a boat until now.

Now I've got my hands full will this little baby and a 200hp V6 Mercury Black Max which I haven't even had started yet......:facepalm:

No doubt I'll be posting in the Mercury outboards section when the time comes.....

 

[colbyt]

Re: Johnson 4hp 1982(ish) no spark

If the coils looks good it usually is. You need some fairly specialized equipment to test one. I would verify the following
Determine if an 82 motor has a deadman switch and make sure it is operation. Also the throttle in start position and verify that the linkage is working.
Coils wires and plug wires securely seated.
Point gap at the high point of the cam (.20) I think.
Unlikely the problem but make sure your magnet in the flywheel is good. Have read that if it will hold a screwdriver in a vertical position that it is good.
If you don't have a nice blue spark after checking that it most likely is the coils. They aren't all that expensive

 

[bobjob]

Re: Johnson 4hp 1982(ish) no spark

Thanks to everyone who helped me out, some really good info which I will be keeping for future reference.

I isolated problem to one of the coils, took it off and cleaned the HT spike and presto! Got two sparks! Not sure why I couldn't get one before but all seems well now, took off the carb and cleaned it and it runs... very happy, sounds like a little cracker too.

I noticed the casing around the defective coil is cracking up, other one showing signs of age too, should I change them? Like I say they are working now maybe i could apply some glue/sealant to the cracks to stop water ingress?

Also I have had it ticking over but turned it off pretty quick so I don't overheat the engine, I just wanted to ask which holes are the water inlets so I know how deep the water in the bucket needs to be and also where is the outlet, I understand they don't "squirt" water like many other o/b's do but would like to know exactly where the "mist" they create is going to be coming from.

And finally can I use motorcycle 2 stroke oil?

Many thanks, happy Bob.

 

[nwcove]

Re: Johnson 4hp 1982(ish) no spark

if the coils are showing signs of cracking ( odd for modern coils), you should replace them , as they will let you down at the worst possible time.
when running in a barrel, you need to make sure the impeller is submerged as it wont self prime . the mist should come out of the upper exhaust relief holes.
dont use two stroke oil designed for air cooled engines, use only tcw3 rated oil.