503 vapour lock ?

[barandbrew]

Hi All

 

Had a problem with my 503 yesterday. After a hour and half flight and decending from 4000' on low revs 3500 when I applied full power the motor would choke at 4000 revs I eventually applied choke briefly and the motor then restored to normal opperation. I tried to get the motor to do it again but without success. I have new filters, plugs and fuel is fresh. Any ideas would be appreciated.

 

John

 

 

[Yenn]

Could be air filter, have you been flying near grass fires lately?

 

 

[Wilfred]

have you considered carby ice

 

 

[freddy]

hello,

 

It sounds as you may be very lucky. Do you have points or dual CDI.

 

If you have points, check the timing. When it is slightly out it can do very funny and intermittent things like your problem. You should also never descend on low power. Firstly the engine cools too much. You may have had an overly cool engine and it did not want to run smoothly:crying: . The most severe event would be a cold seisure. Always warm engine every 500' and keep exhaust temp up. Better still take a the long route down with more power on.:)

 

The other problem is lubrication. As the lube comes with the fuel, prolonged low power settings robs engine of lubrication. Always apply power slowly and again avoid long periods of idle power.

 

Hope this helps

 

Freddy