What is the proper timing setting for the cam valves on husqvarna 65021es, I replaced the piston and cant seem to get the time right to get it started

no 1 piston tdc
the cam lobes for no 1 piston should in such a position so that a slight turn of the cam shaft one way makes the exhaust start to close and the inlet start to open or the other way the inlet start to close and the exhaust start to open
this is known as valve rock or valve overlap and occurs when the cam shaft is properly timed to the tdc position of the piston
for a twin cam engine the cam lobes position will be the same operation just that the inlet cam rock will be for the inlet cam and the exhaust cam rock will be for the exhaust cam

Are you needing the twin independent variable cam timing info or is this a cam replacement initial cam timing setting? the variable valve timing itself is dependent upon the part design, and is usually controlled by oil flow (causing the timing to change hydraulically and seems transparent to the driver). However, when replacing the cam, the timing is more of a position issue using the marks on the engine and camshafts to make sure the shafts are in the proper position.
If this is for a replacement, use the marks on the block ensuring the current valve position is the proper in relation to piston position (otherwise your pistons will punch the valves and blow the head)

If its a 2 stoke,"takes gas oil mix", piston in backwards,, ,,,,if its a 4 stroke "takes gas only"...rocker arms need adjusted, or cam not set in proper place during resembly "out of time". Or a. Bent valve/valves,,,in the head, valve will have to be replaced

It is possible that you do not have the correct valve timing and a set of valves is hitting on a piston or two. Recheck the marks and it wrong you will have to remove the cam shafts to allow the crank to be brought up to the right position so that the valves do not get bent.

you are in a bit of a bind. Turning the engine over will result in bent valves so do not touch the crank shaft. you have to loose off all the rockers/ cam followers even to the point of removing the cam shaft. having done that remove no1 cylinder spark plug and by the use of a thin piece of wire turn the crank until the piston reaches top dead center. find this by rocking the crank back and forward until the piston dose'n move up or down check for the crank timing mark next replace the cam shaft and position the cam lobes for no1 piston in such a position that the inlet and exhaust valves move slightly up or down when the cam is moved slightly left or right. this is called valve over lap and with the piston on top dead center means that you now have valve timing for the engine. Cam timing marks can be dot on gear to shiny link on chain or if using a belt a dot on tooth lineing up with mould mark or join on head before starting up do a compression check to prove that there are no bent valves. if you are not mechanically minded enough to attempt the valve timing method it may be cheaper in the long term to let a qualified person do the job

top dead centre the piston , crank timing mark should be on tdc , set cam up to be on tdc aswell ! if you didnt move timing back plate all be ok otherwise you need the setting !

THE SOUND YOU HEAR IS A STRETCHED CAM CHAIN THEY HAVE SELF ADJUSTING CAM CHAIN TENSIONERS ITS TIME TO REPLACE YOUR CAM CHAIN YOU DONT WANT IT TO SKIP A TOOTH AND TAKE OUT YOUR PISTON AND VALVES POSSIBLY MORE

If the cam chain jumped then the tensioner is not tight. Timing is way off and valve hit piston. Need to **** case and replace tensioner, dry time then install new piston and pull vales to see if they are bent.

You need a shop manual to get the proper timing info. Basically, you are timing the camshaft with the crankshaft so the valves open & close at the proper time. If you are off, the engine will run poorly and you might even cause the valves to hit the pistons and cause severe engine damage.

cant tell u how to replace the belt its eith in the engin or on the sidewith a cover over timing belt that is.. to set timinmg when your pistons are fully at top of engine turn back 1/8 of a turn right bf top dead center.. valve chould be closed on 1first clyder if not then this means your on the second strock..has to be on first stroke..turn over again then set piston at top with valve closed..your cam should fall in place..note if u remove the cam MAKE SURE U MARK THE CAP TO THE POSTION AND DIRECTION YOU TOOK IT OFF>> if not you will end up with a warped cam and rod caps wore and warped..