Flywheel mark nowhere to be seen {BE SURE TO READ THIS}

[Rabbit TD]

Its really surprising that German engineers would miss something as simple as the fly wheel bolt pattern not being symmetrical, or at least have a dowel pin to locate TDC marks.

Not surprising at all, really.  They did that for a reason, so that if you remove the original flywheel (to change a clutch) you can only install it one way and therefore preserve the timing marks.  Doesn't make as much of a difference on the 02A and 02J trannys since the flywheel is on the "correct" side instead of flipped.

But now a days, with people swapping flywheels between all different types of cars, it obviously makes sense the timing marks can get screwed up.  The Bentley manuals inform you of this and describe the proper way to re-mark the flywheel for proper timing in the event that you are replacing the flywheel.  I had to do this very thing on my '84 scirocco since someone swapped the flywheel with a different car and the timing marks were wrong.  

In my opinion, it was a very smart way to key the flywheels.  What about the GM symmetrical flywheels that were for externally balanced engines?  Now that was a stupid idea and poor engineering.

Brendan

This was the original flywhel and I used the mark lot's of times to set timing, nothing changed till an Autozone clutch was put in last Summer, pressure plate relocated the flywheel position during it's rebuild process.

[Rabbit TD]

im 99% positive that the marks on a diesel are tdc straight up. thats how it seems when you have the head off an engine with known diesel parts that times perfectly. this wheel is off a 92 EFI gasser. i dont have a bently either, but i wish i did.. so basically just take an infector out and find TDC that way? i kinda have a feeling this is why my pump has to be all the way retarded and still not be retarded enough.

My current 1.6 has the factory mark at TDC - when I pulled the head, I used my dial indicator to verify this from the #1 piston. My last 2 IDI's also had it at TDC.

That's why from now on I will always make an acurate pointer and put a  mark on the crank pulley also for verification in case a pressure plate or flywheel is ever changed in the future.

[Rabbit TD]

see, i didnt think about that when i had the damn thing apart. now im stuck with a useless timing mark and a car that runs OK. it would probably run a hell of a lot better with proper timing marks.

That's one of my main points about this post, to let some of us know that mark can actualy be off and timing might not really be where you think it is and wonder about tuning problems instead.

[Rabbit TD]

According to my Bentley A2 manual, we are supposed to make our own mark on the flywheel. It says this applies to gasoline flywheels butt, I would check it on all. I really don't think this was an Autozone, napa etc problem. VW does all sorts of weird things like this, like what is up with that camshaft sprocket without a key and keyway  :?

No it's not  Autozone or Napa's fault, it's these companies that rebuild theese things for them that evidently don't have a Quality Control metod like a jig to check these things that would make sure they were located right after assembly or different parts from different types of pressre plates are combined which weren't designed to have the marks in the same place.  How many other vehicle use this reverse method of pressure plate and flywheel set-up?  I doubt if they even know it's an issue in a lot of cases at these rebuild facilities and God only knows where some of them are today.

[Rabbit TD]

what is the proper way to re mark your flywheel? ive got a 210mm unit on my diesel, and i didnt realise, until i got it all bolted in and running, that the flywheel was from a gas engine. and im pretty sure they have a 6* timing mark and thats it.

The very most acurate way is to measure piston projection on a dial indicator when the head is off, the second is to use something in the injector or G/P hole that can work like pump timing tool which I would do on number 4 as the piston is in the same place as no. 1 but be sure # 1's valves are closed with the lobes up. It will be hard to hold the indicator while trying to turn the engine to get it exact by yourself as the tool would have to be held very steady or somekind of a combination of a welding magnet and visegrip combination type of holding tool improvised.  If You are 100% sure the engine is mechanicly timed right from  previous check beore a flywheel or clutch change then just put the cam lock in with number one's valves in the right place, put the injector pump pin in and see where your pump is in relation to it's little pointer on the belt end, should be pretty close to the center even at 1.0.  If you are positive the crank is at TDC then use a punch or chisel and make your own mark right at the pointer on the trans., you have to be 100% sure it is there before you do this though.  If you are satisfied the cam and crank are aligned and the pump doesn't have enough movement to put it where it needs to be to be able to insert the pin with the pumps indiator marks centered then you have to move the pump cog a tooth one way or the other.  Loosen the cam pulley to make this easier as it isn't keyed to the cam anyway,just enough to let the pulley slip on the cam.  The pulley will stick to the cam so after you loosen the bolt about 1 full turn or so take 2 scredrivers and drive them in aroud the pully at the center as close as possible to the head and as close to 180 degrees apart as you can, drive them in snug with a hammer just do't go crazy doing this  Then with the cam pre-loaded to the pulley side of the engine then hit the bolt with a hammer making sure the screwdrivers are always tight  after every hit and the pulley will pop and you won't be driving the cam backwards enough to hurt something. Obviously the belt tensioner hasto be loosened first and I should have mentioned it first before any of the adjustment procedure starts and the crank should be marked first as well, very mportant.  Once you have the engine positively timed with the crank right, the cam locked on #1 and the pin in the pump and centered on its marks then tighten the tensioner while the cam pulley is stll loose enough just to be able to spin but not wobble.  This method keeps the crank from creeping away doing this, then tighten the cam bolt.  Now time the pump in the normal method and if the crank actualy is right the motor should run good if you have no other problems compression or fuel deliverywise.  Good Luck and make damn sure the crank is where it is supposed to be befor you make your mark on it, most important part of this whole process. :wink: