please help needed outboard again - Page 3

arkamelis · 30 June 2018, 23:03

ok so i think i may have found what Davie was talking about, long chamber below the fuel inlet elbow, removed screw and inspected the chamber using cotton buds and small thin screw driver and all good, no build of anything.
im hoping this is what you meant Davie

Last Tango · 02 July 2018, 06:15

Splash out and buy a can of freezer.....

200ml Freeze It 20, Freezer Spray - SERVISOL | CPC UK

Once it starts playing up try cooling off the coils and CDI units to see if that helps.

matata · 02 July 2018, 11:39

I'd reassemble the fuel pump after cleaning it well. Dont be tempted to use the old gasket set. Use a fresh new set. Use fresh fuel in a separate portable tank that you can keep close to level with the engine.Can you use a clear fuel line from the bulb to the engine ? Take it for a whizz and if /when the engine starts faultering use the primer bulb to try and gently pump fuel to the fuel pump. Did it need loads of pumping? By pumping did it have any effect on the running of the engine?.If so,all of this would suggest a fuel problem. Does the yam have a filter under the cowl? If so i'd temporalily bypass the new on board filter fitted. Just to eliminate possible causes.
I too would be interested what the plugs look like? Nik

arkamelis · 02 July 2018, 19:08

Quote:

Originally Posted by Last Tango

Splash out and buy a can of freezer.....

200ml Freeze It 20, Freezer Spray - SERVISOL | CPC UK

Once it starts playing up try cooling off the coils and CDI units to see if that helps.

you thinking electrical issue ?

arkamelis · 02 July 2018, 19:36

Quote:

Originally Posted by matata

I'd reassemble the fuel pump after cleaning it well. Dont be tempted to use the old gasket set. Use a fresh new set. Use fresh fuel in a separate portable tank that you can keep close to level with the engine.Can you use a clear fuel line from the bulb to the engine ? Take it for a whizz and if /when the engine starts faultering use the primer bulb to try and gently pump fuel to the fuel pump. Did it need loads of pumping? By pumping did it have any effect on the running of the engine?.If so,all of this would suggest a fuel problem. Does the yam have a filter under the cowl? If so i'd temporalily bypass the new on board filter fitted. Just to eliminate possible causes.
I too would be interested what the plugs look like? Nik

Hi Matata
i already have a new diaphragm replacement kit for fuel pump being sent out as we speak. I also have a 27ltr portable fuel tank, which i will be using the next time i take the boat out, again i will fill it with fresh fuel. and it sits nicely on the back seat pretty much level with outboard.

think its a good idea to use transparent fuel line from primer bulb to outboard, i
guess this could indicate just how good fuel is being drawn up from the pump.
the outboard itself does have a inline filter, which i will be replacing with new one ( though i feel is it really needed has i have a very good big fuel and water separator "new filter" fixed above the main tank ) 10 micron filter. But anyway i will get a new one for the outboard aswell.

also ordered a set of new spark plugs, so again the next time i take it out i will get a good idea of condition after a few runs out, if i get a few runs that is

Last Tango · 03 July 2018, 07:31

Quote:

Originally Posted by arkamelis

you thinking electrical issue ?

I'm just thinking a bit more diagnostics rather than pulling thing to bits one after another.

I'm not saying it's not fuel related...but a 2 stroke engine that size is not going to run full throttle/full load for five minutes on the piddly little amount of fuel that's in the carb bowls. probably about 10 secs is more likely. You've stripped the carbs and cleaned then. I'd call that "due diligence", move on.

If you check the plugs after it's been playing up a wet or cold plug will point to an electrical fault. The exhaust will give some clues. If you're dropping a cylinder with and electrical fault it'll start smoking and smelling of unburnt fuel. There will be a definite vibration from the engine.

If it is electrical and something is failing as it heats up, cooling the CDI and coils with freezer might just expose the culprit.

simonl · 03 July 2018, 11:25

You're sure it's not overheating? If it always happens after a few minutes...?
Assuming not it sounds electrical. Does it happen under load, or will it die whilst cruising? I've had many examples of engines working/revving fine on muffs but running poorly when trying to get on the plane. My favourite approach is to find a quiet slipway & keep the boat on the trailer, tied on securely & load the engine by trying to push the boat & car up the slip. This represents a maximum load. There are some obvious safety issues, but with a sensible attitude (including kill cord - which might not be obvious) you can stay in the boat with the cover off & monitor whatever you like. Have someone else to check nobody comes anywhere near you.

I would put my money on breakdown of the spark under load. The suggestion of freezer spray can give you an instant identification.

A £10 infrared thermometer with laser pointer is a useful tool to add to the box.

charliee · 03 July 2018, 11:53

I totally agree with this statement
I'm not saying it's not fuel related...but a 2 stroke engine that size is not going to run full throttle/full load for five minutes on the piddly little amount of fuel that's in the carb bowls. probably about 10 secs is more likely. You've stripped the carbs and cleaned then. I'd call that "due diligence", move on.
I afraid I can't help with more proactive steps but I would definitely change the plugs and have a good look at the old ones a they can tell a story.

beamishken · 03 July 2018, 12:37

The op has taken the logical approach and checked the fuel system first on an engine that had been laid up and refitted to a different boat. I say logical because its usually free if your doing it yourself and one thing eliminated then move on to more complicated and possibly expensive items.
The thing to do now is fit the parts identified as dodgy and retest before he gets into anything else

arkamelis · 03 July 2018, 20:22

ok
diaphragm parts turned up today, nice new flat ones, i have cleaned the outer gaskets and installed them and the new diaphragms and screwed back together, gentle blow into the fuel lines and sounding abit like a trumpet " is this normal ? ". so gentle sucked and completely air tight.
so im going back to the boat on Thursday to re install carbs and fuel pump, im tempted to bypass the outboard inline fuel filter ( small white one ) that sits close to fuel pump,its a sealed unit. was just thinking until a new one turns up just to eliminate any restrictions , will be using portable tank with fresh fuel, so only thing between fuel tank and outboard will be the primer bulb ( new yamaha one ) and recent re furbished fuel pump and carbs.
fingers crossed, will take a video of the test run this time

arkamelis · 09 July 2018, 19:36

hi
havnt had time to take the boat out this weekend, planing on next weekend 14th, keep you's posted

arkamelis · 14 July 2018, 22:18

couldn't be anymore happier today, after all the stress ive had with this outboard and it not running, finally took boat out after cleaning carbs and fitting new bits to fuel pump and finally its running

was out for about 45mins and got through £20 in fuel ( approximately ) got up to 42 knots with four people onboard so very pleased and no cutting out

think i do need to get the carbs tuned though as it was running a bit bumpy at idle speed.

wanted to say a really big thank all the members for your help and support

https://youtu.be/uV05nO8HfOQ