Outboard won't start!

Re: Outboard won\'t start!

Good little engine, I have a similar Johnson twin.

There's a few things you may have got wrong. Obvious is fuel supply / pump and ignition timing.

You can eliminate igniton problems by putting a spoonful of 2-stroke mix into each cylinder, replace plugs and get pulling. There is every chance it will kick off at some point if the spark is reasonably at the right time of the cycle. If it does you have a fuel supply problem, which could include crank-case seals as put elswhere.

If the above test fails either something is not connected right (try kill switch first), or the timing is desparately wrong. You probably need a timing ring for that engine but I am not sure.

Plug gap is 1mm on mine AFAI remember.
 
Re: Outboard won\'t start!

Chippie,s Quick compression test works.
Plug gap as VicS say,s is bigger on cetain types of ig set ups.
The gap won,t prevent the engine from actually firing.
On the subject of spark plugs,if the engine needs the "wide" type check you have the right spec ,ie if the plug is an NGK for instance, "Standard" type would read something like B8HS--- Wide one--B8HS10. the 10 indicating you would set the gap to 40 thou.
Taint gonna stop the engine starting though!
Still on this pluggy thing are the plugs new? (apolgies if I,ve missed something haven,t read through all the posts!)
Cos if you,ve been pulling the string lots by now they could be fouled.
Sometimes even after you,ve cleaned old plugs and they look ok they don,t work properly.
Use chippie,s test method not the ladder method!
If you have put the flywheel back in the same place and the stator plate(the bit where the low tension electrics sit) you won,t have upset the ignition timing.
It appears to have lectronic ig so "points and condensers" being wired or set up incorrectly aint a problem.
More than enough info has hit you for the moment.Stand back a bit now, digest all the former,back to basics and try again! Good Luck. /forums/images/graemlins/smile.gif
 
Re: Outboard won\'t start!

[ QUOTE ]
If you have put the flywheel back in the same place

[/ QUOTE ] The flywheel should be keyed to the crankshaft. Someone else asked about that earlier, so provided the key is in postion the flywheel must be fitted correctly.
[ QUOTE ]
You can eliminate igniton problems by putting a spoonful of 2-stroke mix into each cylinder, replace plugs and get pulling. There is every chance it will kick off at some point if the spark is reasonably at the right time of the cycle

[/ QUOTE ] What is just as likely to happen is that the plugs will become soaked in fuel and oil then it wont start. Thats why I suggested cautious use of Easy start. Cautious because there is no oil in it.
 
Re: Outboard won\'t start!

Yep the flywheel will be keyed.
Maybe I should have said "As long as you,ve put the flywheel back with the "woodruff key" in situ"
Presumed it has been assembled so.
If not there,s a reason for no go.
Seems JM is going about His new experience of Two Stroke Stripping in a methodical way,presume He hasn,t missed the keway bit? Whadyer reckon Jonathan?
Never used Easy Start in a two stroke, usually stick a bit a 100/1 in.
Suppose Easy peasy has the same affect?
 
Re: Outboard won\'t start!

Well, I'm trying to be methodical... working from fuel entry and through until there is no more /forums/images/graemlins/smile.gif. However, I lack in the understanding of how the engine works properly... just trying to look at things that didn't 'look right'. I am going to try the quick compression test as described earlier first. I can't see too much wrong with that side though - I still think there is a fuel supply issue between the carborettor/crankcase and the spark plugs. The spark plugs are brand new aswell BR7HS-10.

BTW, the flywheel has deffinitely gone back on in the right place.
 
Re: Outboard won\'t start!

[ QUOTE ]
I still think there is a fuel supply issue between the carborettor/crankcase and the spark plugs.

[/ QUOTE ] There is nothing there to cause an issue.

If you are sure that the fuel supply to the carb is OK, that the float and its associated needle valve are OK giving the correct fuel level in the float chamber, that the jets and passages in the carb are Ok, that the throttle valve and choke are operating Ok Then there is nothing much else fuel wise to look at.

The carb is bolted onto a small intake manifold which is itself mounted on the crankcase with only the leaf valves between them. The fuel air mixture enters the crank case as the piston(s) rises to the top of the exhaust/compression stroke then as the piston decends again to the bottom of its stroke the partially compressed mixture is forced into the cylinder(s) via "transfer ports" It is then compressed by the rising piston. A clever design of the porting and the the piston crown enables the rising piston to both expel the exhaust gases and compress the fresh fuel air mixture on the same stroke.

There is nothing there to go wrong if you have put it all back to gether as it was and it is all sealed up properly. From what you said previously there seems to be some doubt about the crankshaft seals

You have used new gaskets haven't you? There does not seem to be a gasket between the two halves of the crank case so presumably that joint has just a smear of Hylomar or similar.

Chippies quick compression test may be Ok if you know what to expect so compare it with the same done on a good engine. If you have a car type compression tester expect to get around 80 to 90 psi

Just how much of this engine did you dismantle?
 
Re: Outboard won\'t start!

[ QUOTE ]
If you are sure that the fuel supply to the carb is OK, that the float and its associated needle valve are OK giving the correct fuel level in the float chamber, that the jets and passages in the carb are Ok, that the throttle valve and choke are operating Ok Then there is nothing much else fuel wise to look at.

[/ QUOTE ]
Vic,
I know 100% that there is fuel being supplied to the float valve arrangement... I've taken it apart and its full of fuel. I also know that the choke is working OK too. As for the float needle and the jets I don't know.

I have also bought new gaskets for everything.

I took everything off that was required in order to access the pistons, but I didn't take apart any of the items that I removed, i.e. carb.

The leaf valves have all been put back together correctly (there is only one way round) and all sealed properly (they have new gaskets either side too).

I have ordered the manual that you posted about too.

I was only saying a fuel supply problem between carb/crankcase because I have tracked it as far as this and then the trail ends. However, you have a far greater knowledge on outboards than I do, hence why I posted on the forum /forums/images/graemlins/smile.gif.
 
Re: Outboard won\'t start!

Ok then

I'm not sure what fuel tank arrangement you have. Integral with gravity feed or a remote tank with a primer bulb and fuel pump (activated by pressure pulses from the crankcase or even some form of saddle tank with a priming pump? I noticed the latter on the engine diagrams but it is not something I am familiar with. Also there seems to be some form off shut off valve associated with the carb that I am not familiar with.

You need to be certain that the carb float chamber is full to its correct level (and that the needle valve that the float operates is shutting off the flow when the float chamber is full). If you dismantle the foat chamber look out for the needle as it may just fall out. If it does it goes back pointed end first.
I have had a float / needle valve stuck in the closed position on a totally different engine. I don't know how or why as it freed itself as I was investigating.

Once you have established that the float chamber is correctly filling and not flooding the next thing to consider is that the jets and orifices in the carb are not blocked. That really means stripping it all down and cleaning everything through cautiously with some fine copper wire (copper because it won't damage anything) but you must be careful not to break the wire off in a jet. I have not had to work on one of these carbs so I suggest you wait until you have a manual as I can't go into any detail The manual should tell you a basic setting for the slow running adjustment but note how many turns it is screwed in as you dismantle it. I think that is the only adjustment. (Earlier models had a fast running adjustment as well)

You seem to be convinced that it is a fuel problem which is why I suggest thoroughly going to town on the carb but you will probably need a carb overhaul kit unless you are very carefull with gaskets etc. Personally, bearing in mind the dismantling you have done I would go for the ignition system, especially the timing, first

Once you have satisfied yourself that the carb is OK then there really is no more to the fuel side although I am worried about the state of the crank shaft seals by your earlier remarks when they were mentioned.

I am not convinced that trying neat fuel as suggeted earlier will work. Its worth a try I suppose because if it does fire even once or twice it points to a fuel problem rather than an ignition one. However if it doesn't it tells us nothing. Engines run on a finely atomised mist of fuel droplets, mixed in the correct proportion with air, thats the function of the carb, not on petrol vapour. However if the ignition is Ok then a squirt of Easy Start (which is ether or at least is based on ether) into the air intake will almost certainly produce results.

Once the carb is dealt with the only thing remaining is the ignition system. If you are getting good fat juicy sparks at the plugs then you will have to check on the timing with the aid of the manual. I would want to be certain that the LT wiring between the powerpack and the coil unit is correct and that No 1 plug was not sparking when No 2 should be and vice versa. It may or may not be possble to get the wiring muddled up. I do not know
 
Re: Outboard won\'t start!

Thanks Vic.

As said before, you seem to have a very good knowledge on outboards. Do you work with them, or just a DIY fan?
 
Re: Outboard won\'t start!

Just DIY I have a 6hp Evinrude so some similarities with your 4hp.
Always dabbled with engines. Stripped a couple of car engines down to the last nut and bolt, several gear boxes as well. Never dismantled a back axle though! It all started about 40+ years ago when I could not start my car the day after it had been serviced and I realised I had paid a garage to do what I could easily do my self and without f...ing it up. Never trusted garages ever since. An attitude supported by the mess the local people made of my Peugeot diesel engine a few years ago. It cost me more to get their handiwork put right than the car was worth. I still do the routine servicing myself except for the wifes new Renault. There does not seem to be much under the bonnet of that which I recognise. I think I know where the oil filter is hidden but I still have not found the spark plugs and I have not the faintest idea on the fuel (petrol) injection system. I expect one day I'll buy a worshop manual for that and start working on it.
 
Re: Outboard won\'t start!

A google search for 'twostroke engine animations 'will provide some good illustrations. For some reason the link wont post directly here.

Those Evinrude/Johnson twins are great little motors. I've got one going that had been submerged, I didnt want to do the whole disassembly so flushed it with very oily fuel mix through the engine and cleaned the carb, blew it all dry with compressed air and away she went. It's been going for a few years since then.

I think your float needle valve will be ok if fuel is getting through to the cylinder. If it was leaking you would probably see fuel running out from the carb or seeping around the bowl gasket. If your carb has a brass nut in the bottom of the float bowl, undoing it with the fuel connected will let fuel run out which tells you the needle valve is opening. You can also check if it is shutting off by connecting the fuel with the float bowl off and gently pressing the float up with your finger. I cant see how the float level could have changed from the last time you used the motor unless some pressure had been applied to the tang on which the valve sits.

The neat fuel trick suggested does work. I like to gently pull the motor through a revolution first so there is no large amount of fuel to snuff the plug. The spray start cans work too but dont contain lube oil which can make them a bit risky for twostrokes. The Aussies make a good one called 'Start Ya B'stard'- a great name I reckon.

I have occasionally got twostrokes with doubtful seals going by squirting oil (about a tablespoon or more) into the plug hole and pulling the engine over with the plugs out two or three times so that the oil gathers around the seals. If the engine coughs even once you know you are on the right track. You may have to clean the plugs two or three times but she will fire and keep running. Lots of smoke though. The other way to get a motor with weak seals to fire is to use an electric drill with a socket as a starter, often the higher turnover speed will generate enough pressure to fire the motor.

Keep us informed
Good luck!
 
Re: Outboard won\'t start!

Unfortunately there is deathly silence. All I can hear is the pistons moving up and down, and if the spark plugs are removed then the sort of popping sound as I suppose the air is moving in and out. I have ordered the manual, so will read that before I start to venture further into the carb/float arrangement - I think it is going to be something in there, I just don't really know how it works to start stripping it apart.

I will keep the forum informed as I progress.... hopefully /forums/images/graemlins/smile.gif
 
Re: Outboard won\'t start!

"Deathly silence" Hmm something is truely adrift.
Have you taken the carb apart or just removed it?
If you like, PM me with the total description of what you have dismantled and how far you stripped the Motor down. Give as mutch info as you can, then when your book arrives Me or Vic can probably sort you out! /forums/images/graemlins/grin.gif
 
Re: Outboard won\'t start!

I accept that you believe the problem is fuel related and it may be that in time you will find that the carb is well and truly fouled up.
However before you start ripping it apart to clean it can you look at one thing on the ignition system.
You can recognise the "coil assembly" by the fact that it has the plug leads connected to it. Also connected to that unit are two thinner leads that go to the "power pack". Is it at all possible that these two leads have been swapped over at one end or the other. If it is possible I suggest you do swap these over and try again to start the engine. If they are connected wrongly then the top cylinder will be sparking when the bottom one should be and vice versa.

If these leads cannot be connected wrongly or if you marked them and know for sure that they are correct forget I spoke!
 
Re: Outboard won\'t start!

Nope, not taken the carb apart just removed the float bowl from the bottom and then took the carb off the head.

And to your other question.... I took off virtually everything. I didn't take the bits apart only removed them from the main engine.

Vic... I will do as you say and check all possibilities - it would certainly be easier than stripping other things apart again. And to one of your previous questions, I am keeping the impeller wet by putting the engine in a bucket of water whilst attempting to start.
 
Re: Outboard won\'t start!

i have a 1965 johnson sea horse(6hp) it has a knob between the pull start and choke for lean and rich can anyone tell me the base setting for this? Many thanks
 
Re: Outboard won\'t start!

I'll be interested to know. I have a 7.5 in the garage at the moment, in pieces and I wondered the same, although I haven't altered it and it was running well when I removed the knob. I've just checked and the knob will screw in (richen) one turn before stopping. Which means it must be an air bleed as unscrewing it weakens the mixture.
On my Honda the setting was screw it down and back off one and a quarter turns.
If you are completely in the dark, I'd suggest closing it off and then winding out one turn. It's only the tickover mixture, so you'll be able to tell if it's running OK, all else being set correctly (plugs, tickover speed)
After each adjustment rev the motor slightly and let it settle down again.
 
Re: Outboard won\'t start!

Thanks for that will give it a go!! the motor has been in the back of a friends garage for 5 years!! managed to prime the carb with some mix from my seagull, the second pull and it spun over but only for a couple of seconds, but at least that shows promise!!!!
 
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