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Old 02 August 2004, 18:27   #21
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Quote:
Originally Posted by brucehawsker
Do you mean take out the brass screw all together?
Yup.
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Old 03 August 2004, 03:35   #22
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What JW said is spot on, the 2 to 3 turns out on the mixture screw (the one with a spring behind in the side of the carb) is always a good starting point on all engines 2stroke & 4stroke.
We have had this slow running problem a lot with Auto-lube two stroke engines, especially after leaving them unused for a time.
It has always been the same thing, blocked slow running jets within the carbs.
Is your engine still under warranty?
If so why not take it back to let them sort it out, if its outside the warranty period it looks like you are going to have to take the carb off and clean it out.
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Old 03 August 2004, 06:17   #23
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Sorry Jackwabbit but, from what Bruce has said, it seems, in this case, the one with the spring around it is the tickover adjustment and the mixture screw is inside a hole.
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Old 03 August 2004, 07:46   #24
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oops OK so they keep changing things but it still sounds like slow running jet or hole or whatever they have put in this time.
Whatever it is I hope you get it sorted soon.
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Old 03 August 2004, 14:37   #25
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Sorry I am a wimp

Thank you for all your help. Called Suzuki dealer this am. They confirmed it was the slow running hole which was blocked. Need to take carb off in their view. Offered to do it under warranty when I am passing Lymington tomorrow so bit off his arm. Said he'd show me how to do it.

It is great you all arrived at the corrrect dianosis - sorry that I am too much of a wimp to try and sort it myself - I am getting out of my DIY level of competance!

Cheers

Bruce
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Old 03 August 2004, 17:20   #26
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Idle jets blocking up can often be caused by leaving fuel in carbs when you store an engine, IMHO if you're not going to use it for a week drain the carb either by disconnecting the fuel line and running all the fuel through the engine (give it full choke as it starts to falter) or if you are lucky enough not to have a Johnson use the drain screw! This has cured 'faults' in several engines and is well worth while as a matter of course.
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Old 03 August 2004, 18:23   #27
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Quote:
Originally Posted by brucehawsker
They confirmed it was the slow running hole which was blocked. ...........- sorry that I am too much of a wimp to try and sort it myself
I'm kinda sorry you didn't do it yourself. You missed out on the satisfaction it brings. Next time...
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Old 03 August 2004, 18:55   #28
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I thought I would just add a wee bit about outboards and carbs while we're on the topic.

Carburetters do not normally flow only fuel through their internal passages. The main system will have a jet, often referred to as the 'air corrector' which feeds air into the top of an emulsion tube. The main jet feeds fuel into the bottom of the emulsion tube. The air and fuel mix and it is this emulsion which isssues from the main nozzle as fuel.

The slow run system is normally similar. Additionally, at tick-over, air is added to the mixture via the progression holes which are on the atmospheric side of the throttle butterfly. As the butterfly opens, the progression holes are gradually subjected to inlet tract depression and they begin to flow some of the emulsion and so provide extra fuel during throttle opening. As the butterfly gets close to leaving the final progression hole, the main system should begin to splutter fuel and then begin to supply the whole of the engine's fuel requirement. This transition can be a problem area and it is a good reason for ensuring the fuel chamber float level is correct.

This emulsion air will usually be drawn into the front of the carb via the airbox and herein lies a problem. Outboard motors do not usually filter the inlet air so any bits of bugs, leaves, seagull wings etc. are able to enter the small fuel passages inside the carb. Plainly, this makes outboard motors more suseptible than road vehicle engines to dirt contamination problems.

There will also be a fuel enrichment device but we'll leave that for another time.

Here endeth the wee bit of gospel.

I just thought it might be useful to someone.
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Old 20 August 2004, 14:54   #29
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Final Report on this

You was right. It was the slow running whatever that was blocked. Now runs fine. How important is it to run the engine out of fuel each time? I use mine every three to four weeks. But it takes a lot of pulling to get fuel back into the carb if I run it dry. Hence decididing to leave petrol in while stroing in the garage.

What are your thoughts?

Thanks

Bruce
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Old 20 August 2004, 15:26   #30
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Quote:
Originally Posted by brucehawsker
You was right. It was the slow running whatever that was blocked. Now runs fine. How important is it to run the engine out of fuel each time? I use mine every three to four weeks. But it takes a lot of pulling to get fuel back into the carb if I run it dry. Hence decididing to leave petrol in while stroing in the garage.

What are your thoughts?

Thanks

Bruce
Phew, I'm pleased to hear that. Distance engineering is tricky!
----

Doesn't pumping the squeeze bulb fill the carb?

I've never found any difference either way. Some folk swear by one or the other. I'd just flush it out, wrinse it down and put it away. Give it a scoosh of grease occasionally.
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