MS461 won't idle

[Kebo57]

I’ve bought a ms461 spares or repairs no carb
I've fitted a HD 16 carb left over from previous project
The saw will run & rev but wont idle
I've checked everything barrel & piston, rings, inlet manifold, impulse hose, crank bearing seals, fuel pickup pipe, air gap.
Stripped the HD 16 lowered & raised the inlet control leaver checked metering diaphragm removed the high & low speed caps for extra adjustment
Fitted the carb from my 046 good running saw and the MS461 won't idle with this car either

Is there a reason why this 461 won't take a HD 16 carb

Below are the carbs listed for 46 saws
Stihl 046 HD 14, 16, 24 HD 8, 9
Ms460 HD 14, 16, 24
MS461 HD 50 & HD51

Any help would be greatly appreciated

 

[Kebo57]

Got a bit more info to add
The compression is 180 psi
With the 046 carb fitted it will start
but idles at about 3-4 k rpm with the idle adjust screw no where near the cam,
The saw responds to the low mixture adjust screw the saw will die to lean & to rich so is responding to the low screw should that happen when it’s running at 3k approx rpm

I think the metering leaver might be set to high its 0.020” above the carb body
Once again any help would be greatly appreciated

 

[Kebo57]

Had another go & decided to rig a pressure test up and found what’s going on.. air leak between back of cylinder to crankcase
The baffle holding down screws are standing proud of the crankcase by tightening down the cylinder head it’s left two witness circles in the head see pic
Looks like the head isn’t the correct one for this 461
3rd pic is supposed a genuine 461 barrel no relief for screws so could be the wrong screws..
Got the 461 working as it should face screws of in lathe reassemble it set carb as normal
Got mi self a MS461 180psi for £70 + 2 covers and a few bits & bobs
Next job is bore clutch drum to 18mm & fit 3.5mm needle rollers in existing cage