Carb Icing on ETZ125

[HENRY]

Does anyone have this trouble when it gets colder? Starting as normal, then after 3 miles down the road it sounds like a strangling noise. The fuel is being restricted to the engine. My workplace is 6 miles away so by the time I arrive the bike is about to stall unless the throttle is kept on. I've read about carb icing elseswhere - my throttle is kept half open during the ride at 30-40 mph/4 to 5000rpm average. The carb is 1987 but the jets were renewed recently. Its not always the fuel cap blocked full of bits, by the way. I check this as well.

Its the same every Winter!!! Has anyone got a solution, please?

Paul

[radiograf]

I've had this problem on my ETZ251. The solution is to add Fuchs Silkolines Pro FST to your petrol, It can be bought from your local silkoline supplier (the may have to order it in) or of course from EBAY. Its not cheap, (I've just paid £15.00 for a bottle) but as you only need 20-40 ml to a tank, a 1 litre bottle should last quite a time.

[DAVID THOMPSON]

a winter time shield that directs some heat from the cylinder head fins and cylinder fins back past the carb body
may help also or into the air intake even a 6 or 12 volt lamp in the air cleaner

i used to run a 20 watt bulb in the air cleaner of an old vw bug to help it on real nasty days
but mount it where it will not get the filter toooo hot
dave

[djsbriscoe]

This is not an "ICING" problem. That is unless hampshire has become as cold as Canada (Hampshire is on the UK's south coast). Have you checked the float level in the carb?

David.

[HENRY]

Thanks for your responses

I will check my float level. Other thing is that fuel blows out of the air screw and throttle scerew; also the last time I took off the air filter I found mixture in the bottom of the conneting hose.

Any ideas, please?

Once again I'm grateful for your help.

[djsbriscoe]

The carb is overflowing due to a defective float valve. Buy yourself a haynes manual (http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0264078526) or join the mz_riders yahoo group (http://groups.yahoo.com/group/mz_riders/) who can give you the float height information.
This depends on if you have a BVF or Bing carb.
Before you check the height you need to replace the float valve and float bowl gasket. Do this anyway as it saves having to dismantle the carb again later. Part can be bought the same place you got the jets or Burwins in London.

HTH.

David.

[Skorpion]

I have to agree with David.

You must check the carburettor float valve as fuel should not escape from the carb screws.

But Carb icing has nothing to do with freezing weather, if you look it up on the net, but a combination of the Dew Point and Temperature,

I personally have never experienced carb icing, but if the problem still exists after you have done the carb, try the Fuchs Silkolene Pro FST, it wont do any harm.

[HENRY]

I am just looking at some of my topics that I started off and would like to conclude on this carb problem I had posted here over two years ago:

After checking the float height and then the fuel height on my carburettor (as accurately as possible using a see through yogurt pot and calliper tool) I noticed a confliction between the two measurement specifications. Manual states with carb upright: 33 + 1 mm; carb inverted: 27 + 1mm; level 12 + 1 mm.

I chose to prioritise with keeping to the fuel height to the manual's specification and then readjusting the float to get this. I had previously tried with the float height specifications before and getting no success with the problem. I could never understand about how to get the correct fuel height until I thought about the see-through yogurt pots.

The manual advises to inspect the float and needle valve but I didn't (for what, nothing was apparent?).

We had an unusually very cold winter (2011-12) for the south of England (UK) with temperatures one night of -6. After doing these adjustments I rode my bike into work (about 6 miles) at a steady 30 mph throughout without a recurring incident and it has been okay since over the last winter as well.

Thanks everyone for your help.

[davegsm82]

I've experienced Carb icing on a ETZ125 before, but it was about -12 degrees and I was riding in snow and ice (never again). The outside of the carb literally became a solid block of ice, the intake started to become restricted by ice accumulating on the inside of the wall.

 

Eventually it came to the point where I was holding full throttle just to get home on idle.

 

Evaporation is a powerful effect.

 

Dave.