Hi my sons 2002 Punto is due for a new cambelt. Have read several threads and most refer to setting the timing to TDC. The engine had two cycles, one on the firing stroke the the other on the non firing stroke. The question is. If the engine is set with the timing marks as per the recomendations, the old belt removed and the new one fitted without moving either the cam or crank pulleys, does it matter if it was on the firing stroke or not. I know you can look through the bel housing for marks on the flywheel but it is difficult to get a good look at the flyweel below the hoses etc
Technical Cambelt change
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Technical Cambelt change
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which engine my friend?
Assuming 1.2 8v here
remember the crank will need to turn twice, to the cams ONCE
As long as the timing marks align back up after been turned over, then it'll be fine
Ziggy
Assuming 1.2 8v here
remember the crank will need to turn twice, to the cams ONCE
As long as the timing marks align back up after been turned over, then it'll be fine
Ziggy
is you punto a 8valve or 16valve?
there is plenty of info on the timing with pics on the 8valve on forum
more info than say Haynes manual.. search button is worth a press,
if 16valve its more technical but its easy to work out,
hence why iasked if you have 8v or 16valve,
there is plenty of info on the timing with pics on the 8valve on forum
more info than say Haynes manual.. search button is worth a press,
if 16valve its more technical but its easy to work out,
hence why iasked if you have 8v or 16valve,
Assuming 8v, just line up the marks on the cam and crank pulley. The plugs fire on compression and exhaust strokes (wasted spark), so you've no need to worry.
If 16v, you need the timing tools, or there's a good possibility of bending valves.
If 16v, you need the timing tools, or there's a good possibility of bending valves.
Many thanks for your replies. Yes it is a 1.2 8v. I assume that if I line the timing marks up on the cam and crank and replace the belt rotating the engine by 2 cycles and they still line up it does not matter that the initial setup was on the waste cycle rather than the fire cycle
Yes.
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make sure water pump replaced at same time or tension of new belt will wreck its bearings in near future
Line up the marks. The top one is clear the crank mark less so. Lining up is important as it ensures that the valves are not going to move the camshaft when you release the tensioner. You will see that one mark is at a tooth the other between two teeth. Mark the old belt and both pulleys with wax pencil or chalk at the two marks. The new belt is probably already marked with two white lines on the back to help placing it correctly.
Compare the old and new, count the teeth, count them again
if you're like me, transfer the old marks to the new if required and put the new on in the same place as the old. The side opposite the tensioner should have no slack, the tensioner will look after that on the other side.
Compare the old and new, count the teeth, count them again
if you're like me, transfer the old marks to the new if required and put the new on in the same place as the old. The side opposite the tensioner should have no slack, the tensioner will look after that on the other side.
