Where is the mixture adjusting skrews?

Post by **kloppen** » 12 Feb 2005 06:30 pm

Hi

I have a 360 85 with a B200K engine (see pic)

I think I have a to rich mixture and I really want a slightly lean one.

So do anyone know where the screws are? and is it dangerous to adjust this on you own?

Picture-answer is the best for me...

this is my engine and my carb.

What is the hose on the left top that goes into the top of the carb.?

Post by **redline** » 12 Feb 2005 07:00 pm

looks more like the car is suffering from dandruff LOL

Post by **kloppen** » 13 Feb 2005 02:08 am

hehe..
It was snowing heavy under the "photoshoot"...

Post by **foggyjames** » 13 Feb 2005 04:41 am

The hose that goes into the black plastic housing? That's the crankcase ventillation hose.

The mixture screw is (I think) located in the base-plate of the carb. If you took picture 2 from a lower angle, you'd see it. Post up a picture like that, and I'll circle it for you.

cheers

James

Post by **kloppen** » 14 Feb 2005 08:03 pm

The ventilation hose, is it suppose to come misty smoke that smell like petrol out of it? The crankcase, what is that?

And to the carb.

I have drawn some arrows to possible screws. Can someone please tell me what these are for.

I can't see any schrews in the base plate under the "wireconnection point" in the last picture. (couldn't get any lower)

Post by **foggyjames** » 15 Feb 2005 01:16 am

kloppen wrote:The ventilation hose, is it suppose to come misty smoke that smell like petrol out of it? The crankcase, what is that?

Not really...when did you last clean / replace your flame trap?

kloppen wrote:

The idle circuit mixture screw (as far as I'm aware) is behind that throttle spindle, almost exactly where you've pointed to. I'll try to get a picture of mine tomorrow.

cheers

James

Post by **kloppen** » 15 Feb 2005 02:39 pm

What is the "flame trap"?

And is it just one screw to adjust the mixture. I thought it was one for fuel and one for air...

Post by **foggyjames** » 15 Feb 2005 03:22 pm

The flame trap...I'm not exactly sure where it is, but I think it's in the box on the other end of the pipe which runs into the plastic moulding on the top of the carb. You're looking for a clear plastic 'filter' around the size of a mid-size coin in the middle of that box.

The mixture is a ratio of fuel to air. You're adjusting the amount of fuel bled into the air stream on the idle circuit, therefore altering the air/fuel ratio (ie: the mixture).

cheers

James

Post by **kloppen** » 15 Feb 2005 07:31 pm

Can I ask which way to rotate for less or more fuel?

Clockwise or "against the clock"?

Post by **foggyjames** » 15 Feb 2005 08:51 pm

No idea, sorry! It ought to be pretty obvious when it's going rich though - black smoke!

cheers

James

Post by **wjp01908** » 15 Feb 2005 09:57 pm

Usually clockwise goes leaner, ie less fuel - think of it as screwing down a tap.

Unless you have an exhaust gas analyser you`ll have to do it by feel.

Screw it in until the engine starts to misfire and begin to run badly. (Mix too weak)

Blip the throttle a bit to settle it and slowly screw it out until the engine begins to "hunt". (Mix too rich)

Somewhere between these two settings will be your sweet spot - gently feel around it blipping occasionally to settle it until you get it just so. Usually the engine speed will vary a bit during adjustments and the sweet spot will be where it is the highest.

All a bit Zen really and one of the reasons I prefer a carb.

Natch all of this with a fully warmed up engine - an italian tune up beforehand is often helpful

Will

Post by **foggyjames** » 15 Feb 2005 10:36 pm

wjp01908 wrote:an italian tune up beforehand is often helpful

An italian tune-up is always useful

cheers

James

Post by **kloppen** » 16 Feb 2005 07:29 pm

an italian tune up? Sorry, I don't understand...

Post by **wjp01908** » 16 Feb 2005 08:12 pm

Italian Tune Up:

Find a good bit of road and basically thrash the pants off of the car for about 1/2 an hour, getting it good and hot. Blows muck out of the engine, removing carbon deposits and the like that can build up if the car is mostly used for bumbling around town.

Will

Post by **SteveP** » 16 Feb 2005 08:17 pm

Mine gets that treatment everyday

.. ouch fuel economy