Originally Posted by Bruce
MVC,

Here is some information from the parts list and manuals area.

Optional top springs for LM carburettor:

CR03417A 150g-I.5N Red

CRO 3643A 200 g-2.0 N Yellow

CRO 3594 250 g-2.5 N Natural

CRO 3638 300 g-3,0 N Green

Vortex and turbo blade disc models which are governed to 2700-3250 rpm have a restrictor installed in the governor vacuum line where it is attached to end cap.

This restrictor reduces the engine speed approximately 150 rpm. In addition to the rest restrictor, the poppet valve in these carburettors must be set with the letter A facing the spray hole. Refer to heading Adjustable Poppet Valve if necessary.

The final engine speed adjustment is pre-set in
factory to ensure that the engine noise level does not exceed The decibel reading requirement. During normal service it is not necessary to change the colour coded spring. cheers2

Ok, an update.

Thanks again Bruce for the info I have pieced it together and I now understand, I think. The 'primer cap spring' is actually the big diaphragm spring? I can see that if Victa had different spring rates for the diaphragm this would affect the rpm's.

The 'gov lug' is the hole in the carby diaphragm end cap that has the hose going to the engine block. I have found both my power torques was clear and open and easy to blow through, but the full crank mower did have a restrictor and only a tiny hole in it, it was also clear and working.

I rechecked the carby valve face and found it is not symmetrical! I needed to look closer before but did not. Here is a blury pic.

[Linked Image from i256.photobucket.com]


I have reset all my mowers to 'A' on the carby valve and found a slight lower ideling on the power torque mowers so this is good! They now are better and more user friendly. I know all my mowers had been set to 'C' on the carby valve before I had got them. I think this must be the normal setting for Power torques and maybe full crank models.

I am more happy now with these set to the 'A' postion.









Last edited by MVC; 20/02/09 02:30 PM.