doing timing after cam belt on a 8v pb gti

[DarnPB]

Fair enough mate.

I've looked at that one and it's all blah blah blah to me!!!  :embarassed:

I'll do some more research.

Set the crank so that No.1 cylinder is at TDC on its compression stroke. There is a notch on the crankshaft pulley, and this should line up at its closest point to a similar notch on the pulley on the intermediate shaft. The intermediate shaft drives the ouil pump and the distributor. At this point, the rotor arm should be pointing to a notch on the distributor case.
The cam shaft pulley has a punch mark on the back of it and this should be level with the top of the rocker cover. You then fit the belt and tension. Check, re-check and check again that everything is lined up as you tension the belt. The belt tension should be so that you can, with a little force, be able to twist it 90 degrees with your thumb and finger at its longest run between two pullies.
Once everything is put back to normal, re-time the engine ignition. To do this, you need to start the engine and let it run until the engine is up to temp. Switch off engine, and disconnect the fan switch. Start engine and remove the connector to your blue temp sensor with engine running. Time the engine at 2500rpm and adjust as necessary. The timing marks are in the little apperture in the bell housing. There is a pointer on the bell housing and a notch in the flywheel (It would be a good idea to paint these marks with tipex or something like that so that you can see them properly in the strobe). The engine ignition should be set to 6 degrees advanced, at 2500 rpm.Once done, reconnect the blue sensor and cooloing fan. (Be carefull here. The fan may start as soon as you connect it.) Tighten distributor and drive!

[richard s]

as stated above but with a bit of faffing on crank and cam as mine kept moving out of alignment when tensioner tightened  but they lined up in the end its just a case of moving them off their marks a bit and then tighten and check if still out adjust and tighten again till you get it right

[Bjork]

I've seen photo's of a green cover that I'm assuming is the bell housing marker but I can't locate it on my car.

I also don't understand the 6 degrees bit. All the rest is making more sense to me now though.

[DarnPB]

I've seen photo's of a green cover that I'm assuming is the bell housing marker but I can't locate it on my car.

I also don't understand the 6 degrees bit. All the rest is making more sense to me now though.

The 6 degree is the angle before TDC on the compression stroke that the spark plug needs to fire at. This is required so that peak cylinder pressure occurs just after TDC for maximum efficiency. You have to realise that the charge in the cylinders does not explode, but burns, and this burning takes time. As the burn takes place, the pressure within the cylinder increases due to heat, with optiminum pressure occurring just after TDC, when the piston is just starting its downward stroke.

For my next lecture, we will be looking at...................

[Bjork]

How do you know if it's 6 degrees? And which way is advanced?

Don't think you realise how easily confused I am. 

[rubjonny]

the green cap should be on top of the gearbox bellhousing, next to the engine block.  You may or may not have one, or it might be white rather than green.  Once you unscrew this you can see the flywheel, helpfully VW have put a TDC mark on the fly to line up the timing belt, and also put a 6 degree mark on there for you so you can time it up using a bog std strobve timing light.  If you look in my digifant FAQ, I have a picture of the 2 marks on the flywheel as seen through the inspection hole

[Bjork]

Cheers Guys.

I have had a look at your how to Rubjonny. Just needed a few things clearing up. It's starting to make good sense now so cheers. 

[rubjonny]

I haam planning a more complete and also more generic timing FAQ, for setting up static timing.  I need a few more pictures to complete it though!

[Bjork]

Look forward to reading it mate.

Can't believe the amount of effort you put into this forum.

 

[Mr Blue]

The whole rev 3 times over 3k thing is only for setting the idle & CO, this doesnt have to be done when setting the ign timing.  I think this could mess up the ign timing as reving it over 3k 3 times puts the ecu in setup mode, so i dont know if the ign advance would end up wrong there...

I had problems when i revved it over 3k and then adjusted the timing. Im still not happy with mine. Its just doesnt feel right?

What sort of pics do you need Jonny? Timing light ones etc?