Did you check the output from the stator before you threw parts at it?

It appears that machine has a Briggs Vanguard?

Typical alternator outputs would be either 28 or 40 volts AC MINIMUM. (don't know which system you have)
Regulator disconnected and HIGH engine speed.

Hopefully a bad stator didn't "fry" your new VR.

I did not do any testing.so how do I test stator

"Typical alternator outputs would be either 28 or 40 volts AC MINIMUM. (don't know which system you have)
Regulator disconnected and HIGH engine speed. "

I checked ac volts from stator 25 volts and checked red output lead to ground 8 volts dc. I have 3 wire regulator

Stator fails the test. Minimum means .....

How do I replace it

This link might help-

http://forums2.gardenweb.com/forums/load/tractor/msg081953326857.html?21

I'd suggest going to the Briggs website and getting the IPL for your exact engine. It'll have exploded views + the correct part numbers.
You'll need Model & Type-
Something like-
350777-1234-56

It could be a Kawasaki also.... Best give Bill some #s.

I had assumed it was a Briggs from this link-
http://www.smallenginewarehouse.com/RepowerItems.asp?Brand=John%20Deere&Model=GT235

If it's a KAW, don't believe anything I said.
I don't know what the stator output for those are.

thanks ,i will let you know how it goes

had a chance to work on mower, service man at deere place said to use a quality meter to measure volts so with a fluke meter ,with battery light on ac output is 31 volts from stator .output on red lead is 8.5 volts dc ( sometimes reading is 12 volts dc . both readings with full throttle .battery volts is 12.5 full trottle and when mower is off . the red light comes on if either the head lights are on or the pto is engaged .mower will run for whole grass cutting ,1 hour .when finished cutting i turn pto off and after approx. 15 seconds the light turns off

Capitalizationatthestartofasentencemakesthingseasiertoread.Idon'thaveaschematic,soIdon'tknowwhatwouldcauseyoursymptoms,butitsoundsliketheVoltageregulatorissuspectataminimum.

I installed new regulator ,could new one be bad ? I checked continuity from two ac side wires to ground and they are open . They are open to each other and on diode test to red lead they both read one way only .Red lead is open to regulator case . Maybe under load something inside regulator is not working properly ?

Thanks everyone for your help .After cleaning connections to just about everything and testing electrical and continuity readings everything checked out ok although I could not test the electric board . I decided to purchase a second regulator and installed it .First regulator must have been bad . Problem fixed .