Can't get the timing right

[JOE REX]

Hi,I have two polos Bby and bky engines.The bky engine was rebuilt by the mechanic.After the rebuilt was complete, the car could only start if the crank sensor is removed and the cam sensor still connected.When you reconnect the crank sensor the car would not start but demonstrate difficulty in the way the engine is cranking.The mechanic had tried everything I,e replace crank sensor,checked the wiring,replaced cam sensor but still car only start if crank sensor is removed.The trouble code talks about the engine speed sensor.From the way it sounds as I crank it while crank sensor is connected, I suspect that the timing is not correct.So I have tried to retime the car myself several times but still its doing the same thing.My timing has been like this : camshaft sprocket holes located and used 8mm drill bit to hold the camshaft sprockets on the holes,the crankshaft set on the TDC mark.When retiming I first remove both the belts then start afresh by installing the small belt after camshafts set on the holes.I strongly feel am not getting the timing correct because am not using the timing tool.May somebody help me how I can get this timing correct. I have tried more than 20 times to retime this car but still no change...

[littlepolo]

Is it firing or running at all?

Do check the crankshaft pulley and make sure you have good line of sight to see the timing marks and that you are looking at the right marks. At the top end, you should be OK with 8mm 'dowels' but its easy to make up a tool from a small steel plate, drill 8mm holes and index OK. After 3 belts I purchased a tool of the 'Bay. IIRC, the belt should not be too tight and should go over pulleys quite easily. If you have an old style vacuum gauge (which can be purchased for around £10 on that well known auction site) it would indicate any timing issues.

[JOE REX]

Hi,yes it is firing but will not start as long as the crank sensor is connected.When I disconnect the crank sensor it will start but cannot rev beyond 4000 rpm since crank sensor is not connected..Which side should the belt not be to tight belt because I have noticed that there is always one side which is slacken and the other side a bit tight before tensioner is fastened. For example the small belt is either slacken on its top side or its bottom before tensioner is fastened. Then the long belt is also slacken either on the side of the water pump sprocket or the idler.If I live the slacken side to be on the side of the idler then during tensioning the tdc mark moves out of place

[Johntheo1]

Is No1 Piston on TDC on its compression stroke?.

[JOE REX]

Hi,yes.Cylinder one is on TDC...