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timing marks on aaz
Posted: 18 Aug 2006, 07:17
by strat1
Hi, can anyone tell me if there are timing marks on the crankshaft pulley on the aaz engine?
If not any suggestions on how to find tdc when the timing marks are lost on the flywheel?
thanks
Posted: 19 Aug 2006, 06:07
by dink
i think the timing marks are on the flywheel
the only way i know without taking out the motor and drilling into the bellhousing would be to take out no 1 glowplug, an carefuly use a thin piece of wood {won't damage cylinder or bore} and watch it rise and fall as you turn the engine over until you are sure you have TDC
Posted: 19 Aug 2006, 07:50
by strat1
thanks, I thought of this one, but there is a pre-chamber so doesn't work, someone suggested that there might be some marks on the crankshaft pulley when it is split which would show when it is at tdc, but it is a long shot, I don't want to have to do all this if the marks arent there.
Posted: 19 Aug 2006, 08:06
by Ivorblueun
I was about to post similar last night till the forum thru it toys out the pram , if you remove the rocker cover and rotate the crank clockwise, watch the valves on no 1 open and close you should be able to work out what point in the cycle you are ie when no 1 inlet shuts and your marker reaches max height you will be tdc on compression check injector pump and camshaft sprockets are aligned. due to the angle of the glow plugs I don't think you will be able to monitor the rise thru the opening, but if you remove the injector and use something soft like a piece of copper wire as you need to get thru the opening in the swirl chamber to reach the the actual bore if you follow the
line the injector would be the opening should be pretty much on the same line.l
Posted: 19 Aug 2006, 16:21
by Simon Baxter
Timing marks are on the flywheel and on the clutch cover plate.
They are viewed through the hole in the bellhousing with the bung in it, remove bung, then the threaded adapter to get a better view.
Using the bit of wood option doesn't really work, you will need a dial test indicator to get true TDC, and I presume if you are asking for the timing marks you are messing with timing realted issues and near enough just won't do! It has to be precise!
Posted: 20 Aug 2006, 08:12
by strat1
Basically the engine came out of a passat, and the timing marks were lost when the flywheel was swopped over to enable it to fit the T3 bellhousing. As we didn't have the passat bellhousing to line up tdc.
Have managed to get close with a piece of wire on the piston and turning the crank, but as you say it would be better to be exact. Can you explain more about your preferred method? would be much appreciated.
Re: timing marks on aaz
Posted: 20 Aug 2006, 08:38
by Grun
strat1,
I have no diesel experience at all but :-
Have a look here
This may give you some ideas along the lines that Simon Baxter has suggested.
Mike
Posted: 20 Aug 2006, 14:14
by Ivorblueun
to set up the pump timing the engine has to all be aligned , what is it you want to do just change cam belt or play with the pump timing ?
Posted: 20 Aug 2006, 19:16
by strat1
I want to be certain that no1 cylinder is at tdc, so I can re-mark the flywheel, then I can then proceed if necessary to time pump etc to ensure van is running at full potential. I currently have flat performance which I think is due to incorrect timing,but have lost timing marks on flywheel when flywheel was changed.
Posted: 20 Aug 2006, 20:52
by Ivorblueun
bit of a catch 22 but if you do what i said previously then tweek the crank if necessary to get the locking pin in the pump sprocket and locking bar in the camshaft its got to be in the right place by my reckoning
Posted: 22 Aug 2006, 22:59
by Simon Baxter
The only constant is the crank, the cam timing is infinatley adjustable and the pump timing is fairly adjustable, by fitting the locking bar and the peg into the pump pulley it is likely to be close, or somewhere near, but not exact as you can take the peg out and turn the engine a few degrees.
Also, the correct way to set the cam is with 2 sets of feeler guages, used to pack out the setting bar evenly.
You will get it close, maybe close enough, only real way is to take the gearbox out and just rectify what the problem actually is. usually some knobber fitting the clutch cover in the wrong place. The dowels only allow fitment of the cover in one position, his can confuse the not so clever amongst us so they take the dowels out
Posted: 24 Aug 2006, 15:17
by strat1
what ive now done is put a bit of wire coat hanger down through the swirl chamber to the piston crown and turned crank until I am sure it is at TDC, then put a dob of hammerite onto the flywheel to give me a mark, then gone back and re-adjusted the cam and pump, seems to be running better.
still feel there is room for improvement, though could be expecting too much
thanks for all the advice, much appreciated