Timing chain On the cam shaft sparket, on the exhaust side, there are 2 markings, which one do I use? The single dot or the 2 dot?

You can find the timing mark on the end of a crank shaft by looking for an indented dot which marks top dead center.
A flywheel is balanced and does not need a mark. However if the wheel you refer to is a cam gear (one or two gears depending on how many cam shafts your engine has) look for 2 dots with a tooth grove between the two dots. A matching drive gear will have a single dot aligned with a tooth on the drive gear. When put together the single tooth marked on the drive gear must fall into the grove marked the the 2 dots on the cam gears.

If you are just trying to time an engine, the belt drive pulley mounted to the crank shaft will have a single indented line. The line can get filled with dirt so you can't see it. Wipe it clean and fill with grove with something to highlight the groove, as with a white or yellow crayon or a dob of bright paint. Associated with the belt drive pulley, there should be a metal plate with line marks spaced on it, with 0 degrees (top dead center TDC) marked on it, When the engine is running, using a strobe light connected to your number 1 spark plug you will see where the timing mark on the belt drive pulley is compared to the metal plate with the timing marks.

22R 4 cyl.Get # 1 piston to TDC(stick the harmonic balancer back on temporary)setting the mark to O on the timing tab,pull the balancer back off and slip the chain on the crank gear after finding the single dot on the chain.Set the mark on the cam gear at very top and put the chain mark on that mark on the cam gear.Stick the cam gear back on the cam and bolt it back on.Your set now.

Exhaust camshaft gear and Intake gears have dots on them, chain has colored links. Align colored links to dots or count 14 links from ex cam dot to intake dot. Make sure that the mark on the cambelt side is set first on ex side. Small hole on ex cam gear (cambelt) side to line up with mark on head.

place no 1 piston at TDC compression stroke. There are procedures for the timing of the balance shafts but if it is only the timing chain I will go to that
Align uniquely coloured chain link with intake camshaft sprocket timing mark-- INT--. ( this will be pointing at the 2 o'clock position)
install timing chain and sprocket as an assembly
align first matching coloured chain link crankshaft timing mark (5 o'clock position)
align the second matching coloured chain link with exhaust cam shaft timing mark--EXH ( at the 11 o'clock position
There is a special procedure to reset the balance tensioner and it is different to the timing chain procedure.

To reset cam shaft timing chain tensioner push piston fully and turn clockwise until locked
Once the tensioner has been compressed ensure the distance from end to end is 2.83 inches . If not repeat the resetting process
vehicles 30.000 miles the tensioner is released when the engine is first started . In vehicles over 30.000 miles manually release tensioner by tapping the plunger
Note cam shaft and crank shaft sprockets bolts MUST only be used once. If you want details on the balancer chain procedure then make a comment in the box
use tension wrench and a degree gauge
cam bolts are tensioned to 63 ft lbs + 30 degrees
crank shaft pulley is tensioned to 74 ft lbs + 75 degrees

diagrams I have show a twin cam set up with 2 balancing shafts. The marks on the cam shaft point to (left cam shaft 11 oclock the mark on the right point to the 1 oclock position. The chain will have 3 black links-- the top black links will be at the timing marks on the shafts with the 3rd black link directly at 6 oclock facing a mark on the gear. The balancer marks both point to the 1 oclock position with black links on each and the 3rd black link will be facing a mark to the 7 oclock position on the crankahaft gear. Everything is done with the piston at TDC no 1 cylinder so get it there before you put the cam shafts in position or you will bend valves. Crank shaft gear is not keyed to the crank shaft. there are dots on the right hand balancer shaft gears and these dots will be as the 2 dots on adjacent teeth either side of a dot on the meshing gear. I suppose that is all as clear as mud but if you got this far then you will see the marks and marked links on the chains

TIMING MARKS ON CAMSHAFT SPROCKET A LITTLE SMALL SQUARE MARK ON TOP BOTH GEAR SPROCKETS ON CAMSHAFTS TIMING MARKS SHOULD BE IN THE 12 OCLOCK POSITION BOTH CAMSHAFT TIMING MARKS SHOULD BE LINED UP WITH TIMING MARKS REAR OF TIMING MARKS ON TOP OF CAMSHAFT SPROCKET HOUSING. IF STILL HAVING TROUBLE WITH FINDING THE TIMING MARKS.YOU NEED A HAYNES REPAIR MANUAL.

4 Cylinder diesel(4JX1) :
1 - Timing mark
2 - Cam pulley
3 - HP Oil pump pulley
4 - Tensioner pulley




6 Cylinder petrol:
Align crank(C) timing notch mark (1) to oil pump mark.
Align cam pulley(L+R) marks(3) to cylinder head marks
The cam belt has 3 marks, 2 lines and one mark that is actually a row of dots. Align the dots to the crank pulley groove mark(2) and align the other 2 lines to the cam pulley marks. Using a clothes peg to hold the belt to the cam pulleys works wonders to keep it in place while fitting. Please note the arrows on the belt and have them point in the direction of rotation - right to left side of engine
W - water pump pulley
I - Idler pulley
T - Tensioner pulley.

If for some reason you need to realign the cams on each bank :
Standing in front of the car and starting from YOUR left , looking at the cams you should see RE, RI, LI, LE on each of the camshafts.(R for right bank, L for left bank, I for intake and E for exhaust) Right bank camshafts are marked with one dot, left bank with 2 dots on the shaft itself. To align the camshafts to each other each cam shaft gear has a mark on it. Draw an imaginary line between the centre of the camshaft and the centre of the pulley. The alignment mark should be between the two along this imaginary line. The result will be that RI an RE will be at the top of each gear. The same with the left bank.

the variable timing wheel should be on the inlet cam. the timing marks should align on cams upper of rear inner belt cover the crank upper of oil pump housing

The timing chain is not that fine, nor do you care about advance with the chain. A single link on the chain is more like 15 degrees, and you will have no trouble deciding which is the best fit.
TDC is always 0, and never 4 degrees advanced.
It is the ignition that is advanced, not the chain. To advance the breathing you would need to either change the cam, or get a variable chain sprocket. But again, you can not tell 4 degrees when putting a chain on. It changes that much at least when you take the slack out.

the 2 single dots on the inside of the gear(side facing the rear of the motor) When the gears mesh together the 2 dots should line up.