Fully serviced outboard - still won't work!! Please help!

[Swell]

I've recently replaced a number of key parts and completed a full service on my 1968 Johnson 6hp, but it still has major issues!

I've replaced the coils, points, condensers and wires to spark plugs, fitted new spark plugs, new head gasket, re-surfaced cylinder head & intake manifold, new driveshaft seals, and cleaned throughout including reed valves & carburettor. The compression has improved over before - 76 psi & 80 psi, so a little low but within limits.

I checked the spark and it produced a crisp blue spark across a 1/4" gap, though not on every pull. Is that to be expected? Presumably it sparks easier across a spark plug gap, and it's asking a lot to jump a 1/4" gap.

I tried starting it last night but it clearly didn't want to go. After numerous pulls I got it running briefly a couple of times on the choke which is a good sign, but it died quickly each time. In theory it should start easily after a couple of pulls.

I primed it a couple of times to ensure there was fuel in the float chamber, and to the best of my knowledge the fuel pump works fine. Should the fuel pump work just when pulling the starter?

My suspicion is that it is a fuel problem, assuming the ignition is ok given the spark test & new parts. Could it be reed valves? I tried blowing & sucking across each of the 4 apertures and they seemed fine with a good seal, though they did open with a bit of a pop. Have I not cleaned the carburettor sufficiently? Could there be an air leak somewhere?

Any help would be much appreciated!

 

[ba_50]

Re: Fully serviced outboard - still won't work!! Please help!

You could try disconnecting the fuel line between the fuel pump and carb after taking the plug wires off, and see if it is pumping fuel while pulling the cord. Tighten the fuel pump bolts too. I don't think that will prove it is a good pump, but at least it will show if you have anything going through it or not.

 

[floatingwoody2006]

Re: Fully serviced outboard - still won't work!! Please help!

intermittant spark sound's to my untrained eyes like a timing issue...Are your marks all on correctly?

 

[lindy46]

Re: Fully serviced outboard - still won't work!! Please help!

After it starts, try pumping the fuel line bulb and see if it stays running. If it runs when you pump the bulb and dies when you quit pumping, then you probably have a bad fuel pump.

 

[58rude]

Re: Fully serviced outboard - still won't work!! Please help!

Spray some premix down the carb throat and see if it fires right up, that will tell you if its fuel or not.

 

[Lostfisher]

Re: Fully serviced outboard - still won't work!! Please help!

I am thinking it it either a problem with the timing or or the ignition was not put in properly. Did you put new plug wires in? get ur tester and a drill and spin the flywheel over with the drill while testing the spark to see if it is missing at all. Also does the motor have a push button stop on it? If so bypass the button and see what happens.

 

[Swell]

Re: Fully serviced outboard - still won't work!! Please help!

I am thinking it it either a problem with the timing or or the ignition was not put in properly. Did you put new plug wires in? get ur tester and a drill and spin the flywheel over with the drill while testing the spark to see if it is missing at all. Also does the motor have a push button stop on it? If so bypass the button and see what happens.

All I did was set the points gaps when the cam was at its maximum opening and then re-fit the flywheel with the key lined up - the only way it will go on anyway. I haven't messed about with the timing other than that. I lined up the points opener with the O of the word TOP on the cam - is that right?

As I say, there is a bright blue spark over the 1/4" gap when I pull the starter cord. That spark is a little intermittent, but it is asking a lot over that distance. Not sure if that's typical?

 

[Mas]

Re: Fully serviced outboard - still won't work!! Please help!

I do not know if there is any wiggle room in in your coils, but the outside should be flush with the "bosses" if they're adjustable.

Mas

 

[Swell]

Re: Fully serviced outboard - still won't work!! Please help!

I do not know if there is any wiggle room in in your coils, but the outside should be flush with the "bosses" if they're adjustable.

Mas

I've fitted them completely flush, so no scope for any changes there.

 

[Tim Frank]

Re: Fully serviced outboard - still won't work!! Please help!

I've recently replaced a number of key parts and completed a full service on my 1968 Johnson 6hp, but it still has major issues!

I've replaced the coils, points, condensers and wires to spark plugs, fitted new spark plugs, new head gasket, re-surfaced cylinder head & intake manifold, new driveshaft seals, and cleaned throughout including reed valves & carburettor. The compression has improved over before - 76 psi & 80 psi, so a little low but within limits.

I checked the spark and it produced a crisp blue spark across a 1/4" gap, though not on every pull. Is that to be expected? Presumably it sparks easier across a spark plug gap, and it's asking a lot to jump a 1/4" gap.

Not IMO!
If the spark is not jumping a 1/4" gap, and is intermittant, you have an ignition problem. I would review the installation of your new components.
If you start investigating the fuel system you may find some issues there, but....you will still have an ignition problem.

Do you have an OEM repair manual for this motor?

You did not respond to the suggestion "Spray some premix down the carb throat and see if it fires right up, that will tell you if its fuel or not. "

That is good advice.

But at this point, you have found a clear ignition problem and if you are going to be systematic in your troubleshooting approach, that is job #1.

 

[Mas]

Re: Fully serviced outboard - still won't work!! Please help!

Make sure the points are 100% clean...not even oils from your fingers! Use an electrical parts cleaner...and double check points gap. Check wiring for possible grounding...try starting the motor in the dark and look for errant sparks.

Are you maintaining constant rpm with the recoil when pulling her over?

Mas

 

[Swell]

Re: Fully serviced outboard - still won't work!! Please help!

Not IMO!
If the spark is not jumping a 1/4" gap, and is intermittant, you have an ignition problem. I would review the installation of your new components.
If you start investigating the fuel system you may find some issues there, but....you will still have an ignition problem.

Do you have an OEM repair manual for this motor?

You did not respond to the suggestion "Spray some premix down the carb throat and see if it fires right up, that will tell you if its fuel or not. "

That is good advice.

But at this point, you have found a clear ignition problem and if you are going to be systematic in your troubleshooting approach, that is job #1.

I have the OEM manual and have followed it except regarding setting up the ignition using an ignition tester which I don't have. I just installed the points and set the gap when the cam was at max opening.

Just to say, it is jumping the 1/4" gap fine, just not on every pull. Should it spark across a 1/4" gap the same as it would a spark plug?

I will check the ignition over but for the life of me I was so careful when I installed all the parts to avoid shorts etc. and was careful to keep the feeler gauge free of any oil. Could it be for example that one of the ring connector tails is too close to a high tension part? Should I just try re-fitting the parts?

I'll try the pre-mix thing first though!

 

[Tim Frank]

Re: Fully serviced outboard - still won't work!! Please help!

I have the OEM manual and have followed it except regarding setting up the ignition using an ignition tester which I don't have. I just installed the points and set the gap when the cam was at max opening.

IMO a spark tester will tell you whether you are OK or not, but if not, it won't tell you why not.

Just to say, it is jumping the 1/4" gap fine, just not on every pull. Should it spark across a 1/4" gap the same as it would a spark plug?

Yes. Otherwise it may start but not run....
Seriously, the spark has to be consistent.

I will check the ignition over but for the life of me I was so careful when I installed all the parts to avoid shorts etc. and was careful to keep the feeler gauge free of any oil. Could it be for example that one of the ring connector tails is too close to a high tension part? Should I just try re-fitting the parts?

Been there, done that, then had to redo it again....a few times...
It takes very little to mess it up, but happily once they are right, mag systems are almost bullet-proof.
Recheck from the points back...and my experience is that if you don't have a lot of experience setting points, you invariably err on the over-gapped side. Too large a gap could cause the problem that you describe. Maybe recheck that first.

I'll try the pre-mix thing first though!

I would fix the ignition first....IF you do have a fuel issue that test will say "fuel problem"....but if you don't , the test may still say "fuel problem" because you have an ignition problem. i.e. if it won't run because of an ignition issue, no carburetor test will tell you anything worth knowing until it is fixed.

 

[Swell]

Re: Fully serviced outboard - still won't work!! Please help!

IMO a spark tester will tell you whether you are OK or not, but if not, it won't tell you why not.



Yes. Otherwise it may start but not run....
Seriously, the spark has to be consistent.



Been there, done that, then had to redo it again....a few times...
It takes very little to mess it up, but happily once they are right, mag systems are almost bullet-proof.
Recheck from the points back...and my experience is that if you don't have a lot of experience setting points, you invariably err on the over-gapped side. Too large a gap could cause the problem that you describe. Maybe recheck that first.




I would fix the ignition first....IF you do have a fuel issue that test will say "fuel problem"....but if you don't , the test may still say "fuel problem" because you have an ignition problem. i.e. if it won't run because of an ignition issue, no carburetor test will tell you anything worth knowing until it is fixed.

Cheers for that response - tells it how it is! I'll have the flywheel off and re-check everything. From what you say I suspect I might have too large a points gap, but I'll keep an open mind.

 

[KB1]

Re: Fully serviced outboard - still won't work!! Please help!

Good turkey day eve!!!

May have overlooked this in the replies, but I didn't notice info as to whether or not the flywheel key was partially sheared or not. Seen this on lawnmowers. Fuel is good, Fire is good, but not when it needs to be. Chasing your tail is no fun! Ask an expert on that!!

 

[Swell]

Re: Fully serviced outboard - still won't work!! Please help!

Sorted - cheers for all the advice.

Just tried starting it again, and it fired after 3 pulls! It runs ok and even idles which it didn't before.

Suspect the plugs had just been drenched with all that turning over but not firing, and it fired up after they had dried out.

I'll run it for a while as is to see how it fares, but I'm still wondering about the points gap after the post by Tim Frank. It idles a little rough so I'm wondering if that could be down to the points being a little too wide? Or could it be the slightly low compression? When I set the points I used a 0.02" feeler gauge and set them so there was a slight resistance on the gauge, but only slight. Should they be tighter?

 

[jonesg]

Re: Fully serviced outboard - still won't work!! Please help!

Next time you suspect flooding remove the sparkplugs and pull it through, it will be obvious if flooded.

WHen I did my old 10hp I replaced everything, plugs, plug wires, coils, points, condenser etc. The parts are cheap enough and at least you know where you stand. After 30-40 yrs any original elecs should be tossed.