Outboard woes

I had an issue once when a full tank would be ok once running but a half tank would have lots of issues, it took a while to make this link as would normally just shake tank and and assume it was plenty, it would prime up on the bulb and start fine and idle ok but as soon as it needed a bit more fuel would die out, it was the pickup pipe inside the tank split, it seems the plastic didn't like modern petrol and went brittle.
Have you tried squeezing the primer bulb just before putting in gear to check? Of course once you stop squeezing fuel can flow back down to the tank as they are a very basic non return system.
 
Just a thought? Could the water pump impeller have got mangled up?
I know it's is also driven in neutral, but is there water tell tale?
 
ash2020 said:
That's interesting. Trouble is, it's nearly impossible to get E5 fuel near here. The nearest petrol station is a half hour drive and they certainly don't have it. BTW, what additive do you use?
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I'm using starbrite fuel treatment which is an enzyme one. When using a lot of petrol (on holiday) I use E10 otherwise E5 or what ever the marinas sell when away. All petrol is dozed.
 
Some years ago, I had classic symptoms of fuel starvation on my Tohatsu 3.5 2T - starts fine, runs OK for a bit then fades, restart, repeat. After cleaning the carb a couple of times, a friend noticed a faint ticking noise which, on investigation, turned out to be the coil's earth sparking where it was bolted to the engine block. Cleaning the rather cruddy connection fixed the problem.
 
I'd take it in for a full service and diagnostic, tank clean, fresh E5 and additive or chainsaw petrol - too many rocks where you are if the motor stops and there isn't a tow boat to hand
 
lustyd said:
making a dust that blocks the carb.
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I run my 2t dry. One reason for this is that i can then store it laying down. My engine starts well unless it's been laid down with fuel in carb then it's terrible to start.
Would the dust you mention be black ? I have inline fuel filter but when carb finally needs cleaning out it often has super fine black dust/silt in float bowl. I've no idea what it is or where it comes from.
 
Rappey said:
I run my 2t dry. One reason for this is that i can then store it laying down. My engine starts well unless it's been laid down with fuel in carb then it's terrible to start.
Would the dust you mention be black ? I have inline fuel filter but when carb finally needs cleaning out it often has super fine black dust/silt in float bowl. I've no idea what it is or where it comes from.
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2 stroke is entirely different as you have oil in with the fuel (on standard ones). The black could be a lot of things including rust from the metal in the fuel cap. Step one is completely clean everything out so you know you’re starting troubleshooting the problem rather than side effects.
 
Egret said:
So with E5 petrol and Mercury or Honda additive, is it better therefore now to not to unplug the fuel and let it run until it stops bot to simply stop it with the stop button - using outboard every couple of weeks or so?
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Rather you than me ... I will continue to run my carbs 'dry' ..... regardless of what fuel quality .... because of GUMS ......

GUMS is when the oxidation of the fuel and temperature cause gum to drop out of fuel and THAT is what blocks the jets ... causes bad starting ... Its also why the advice to store fuel in dark cool sealed containers ... to reduce the three factors that cause GUMS to form : Light, Heat, Oxygen

Ever taken a carb apart and wondered what that sticky goo is in the bottom of the bowl ?? That's GUMS.

We put additiver into gasoline to extend the life of the fuel to reduce this happening ... it happens with ALL gasolines... and diesel actually.
 
lustyd said:
Direct experience, actually. Some of us like to own our engines for years.
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So my ancient Evinrude .. ancient Mariner ... ancient Johnson ... as well as the other various are destined for the scrapper ??

Please do not mix up GUMS and what you claim to be corrosion ... your jets block from GUMS ............ FACT ...

I've been in fuels for decades ... and TBH - it tires me reading some of the rubbish that gets put out ...
 
Refueler said:
So my ancient Evinrude .. ancient Mariner ... ancient Johnson ... as well as the other various are destined for the scrapper ??

Please do not mix up GUMS and what you claim to be corrosion ... your jets block from GUMS ............ FACT ...

I've been in fuels for decades ... and TBH - it tires me reading some of the rubbish that gets put out ...
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Are you quoting ancient two strokes when I several times specified four stroke only? My whole point was that much of the advice here is out of date and no longer applies.

My fuel tank isn’t full of gunk, so no I don’t regard what you’re saying as in any way relevant.
 
Egret said:
So with E5 petrol and Mercury or Honda additive, is it better therefore now to not to unplug the fuel and let it run until it stops bot to simply stop it with the stop button - using outboard every couple of weeks or so?
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I have to say, we keep our inflatable tender on a pontoon with the motor attached (a Honda 2.3 Hp 4 stroke) filled with E10 fuel all season and it never has any problems. This season it's been sitting unused for a couple of months and still runs fine. And I never drain the carb.
 
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Stemar said:
Some years ago, I had classic symptoms of fuel starvation on my Tohatsu 3.5 2T - starts fine, runs OK for a bit then fades, restart, repeat. After cleaning the carb a couple of times, a friend noticed a faint ticking noise which, on investigation, turned out to be the coil's earth sparking where it was bolted to the engine block. Cleaning the rather cruddy connection fixed the problem.
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That's interesting, thank you. It sounds like a one in a million fault but I will deffo have a look.
 
Refueler said:
Whether 2st or 4st ... makes no odds to residual fuel in a carb .... so that's that argument put to bed.

Next please.
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Ah that must be why millions of cars suffer with it.
It’s not put to bed. 2 strokes have oil which if the fuel evaporates clogs up the carb. It also lubes the carb and prevents corrosion.
4 strokes have no oil, but if they have water/ethanol mix sitting in a carb with air then they can and do corrode like any metal does. This blocks the carb.

No I have had no deposits as you describe in your theoretical scenario. I have cleaned the corrosion from multiple carbs on multiple occasions though, and changing to e5 fixed the issue for me and many others on the forum. At this point you seem to be actively trying to prevent people getting a solution to this increasingly common problem.
 
ash2020 said:
Easier said than done. I can't find any E5. Or a Tohatsu agent.
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We struggled to get e5/premium unleaded in Scotland this summer. If you use a small enough amount carrying more and waiting it out can be an option if you’re willing to walk to fuel stations. If not then you may just have to get really good at stripping the carb, and have a good set of carb cleaning tools aboard.
 
lustyd said:
Ah that must be why millions of cars suffer with it.
It’s not put to bed. 2 strokes have oil which if the fuel evaporates clogs up the carb. It also lubes the carb and prevents corrosion.
4 strokes have no oil, but if they have water/ethanol mix sitting in a carb with air then they can and do corrode like any metal does. This blocks the carb.

No I have had no deposits as you describe in your theoretical scenario. I have cleaned the corrosion from multiple carbs on multiple occasions though, and changing to e5 fixed the issue for me and many others on the forum. At this point you seem to be actively trying to prevent people getting a solution to this increasingly common problem.
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Oh Dear .... you really have a problem with this ...

I am in no way preventing people from following your advice .. - I'm just putting out the fact that you are making a mountain out of a molehill ...

I will say this one time more and then leave you to post as often as you like in it ...

The most common reason for blocked jets - is GUMS .... that so-called corrosion is such a rarity - it will never be in same ball game as Gums ...
 
Just rang 12 petrol stations in my area to try and find E5. Thankfully I found 2 Texaco and 1 Shell that stock it. Only a 2 hour round trip so that's not bad.
 
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