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Old 18 July 2006, 08:00   #11
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What is the normal operating temp for an outboard....Same as car? Or lower as it's an unpressurised system?
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Old 18 July 2006, 08:20   #12
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Quote:
Originally Posted by fast fred
in for less out for more.when the throttel cable moves, think that one pulls,
on some Carbs crack open, next thing that needs to happen , full timeing needs to kick in, by full i mean what ever factory says for that motor, 20-22deg max, usally done with a low spot on the trottle cam.
if you havent messed with it it's prob ok.
Fred, thanks although not entirely sure I understand all of it ! The only things I have tweaked are the mixture screws, the idle screw and the throttle stop screw as this was adjusted so that the carbs won't opening fully...I now have an extra 200rpm at WOT

I'll screw the mixture screws back to 1.5ish turns out, and clean the spark plugs (whats the best way to do this?).

Scary, sounds like a plan, thanks. I'll see what effect adjusting the screws has.

Any more help appreciated.

Tim
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Old 18 July 2006, 09:38   #13
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http://www.motocross.com/motoprof/mo...lug2/plug2.htm

just found this. Bit confused now. Need to check my plugs again and take some photos.

Lean = too much air = overheating but then my plugs are (i think) lightly sooted pointing towards to rich a mixture!
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Old 18 July 2006, 10:30   #14
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Tim I would be inclined to get a new plug so you are starting from a known point, your plug could be old, oily etc. Also I would run it under load and then look, it surprising how quickly some plugs look sooty when the engine have been idling for a bit. Des
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Old 18 July 2006, 11:28   #15
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Tim, don't want to teach you to suck eggs but do you have water coming from under the cowling (thermostat outlet on pic) when the engine has been running for a minute or so?
Also if the engine has been stood for a while it's definitely worth stripping the carbs and then putting them back to the base settings as your mehanic mentioned.
Have you got a service manual? shouldn't have too much trouble getting one for your motor as it is relatively young, and they are invaluable.
hope this helps
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Old 18 July 2006, 11:32   #16
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Quote:
Originally Posted by Hightower
What is the normal operating temp for an outboard....Same as car? Or lower as it's an unpressurised system?
I think it's a bit lower as I can put my hand (without scalding myself) in the water when testing if the thermostat's opening in a saucepan. Also they open up pretty quick when the motor is left to idle.
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Old 18 July 2006, 11:54   #17
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aha, so that outlet should only have water coming out of it when the thermo stat is open and letting water flow down the cylinder head (i.e. when it has reached optimum running temp and needs to open to regulate it and keep it close to that temp)? I didn't realise that outlet was purely for the thermostat! I will check it tonight.

I need to get me one of those manuals too, just haven't got round to it. May get mr mechanic to have a look tomorrow.

Thanks Jizm.
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Old 18 July 2006, 12:32   #18
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Yep, the impellor pumps the water up the leg and around the cylinder head, when the water gets hot enough to open the stat, water comes from the outlet under the cowling, doesnt take long. When the stat opens it not only lets the hot water out of the motor, it replaces it with fresh sea water, so the stat will probably partially open and remain that way to maintain operating temperature.
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Old 18 July 2006, 12:35   #19
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Tim, have a look at the link below
here
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Old 18 July 2006, 12:36   #20
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This one may be better

here
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