Stuck on a timing belt replacement - need help

[amcink]

My camshaft sprocket does not have the notch in order to align it with the TDC mark on the head.
I'm stuck since i also took out the crankshaft pulley and the lower timing belt cover so i cannot locate the TDC.
Should i just reinstalled everything and then try to find the TDC for the crankshaft and camshaft.
I also forgot to mention that i have not taken the sparkplugs out; therefore cannot turn the camshaft sprocket or crankshaft
Here it is the camshaft sprocket and camshaft area.

[5Toes]

Clean all that junk off and there should be an arrow

[amcink]

Clean all that junk off and there should be an arrow

On the camshaft or the crankshaft?

[5Toes]

camshaft sprocket

[KEVORM]

It's on the cam gear. There is either an arrow on the inner section of the gear or a line below one of the teeth that will line up with the line on the head. If you have a bentley manual it has pictures of each, there is a PDF of the manual in the DIY section i believe.

[paperplane94]

http://www.youtube.com/watch?v=_XCMSF2wQLE

[seatown88]

I have never see a cam gear like yours and therefore have no experience finding TDC for it, however for the crankshaft you can see a small line on the section where the vibration dampener bolts to(on the last photo you attached) which when lined up with the small notch(can be seen in the 3rd picture you attached) means that the crankshaft is at TDC.

Hope that helps

[E30-325iS]

It's on the cam gear. There is either an arrow on the inner section of the gear or a line below one of the teeth that will line up with the line on the head. If you have a bentley manual it has pictures of each, there is a PDF of the manual in the DIY section i believe.

This sounds right, but you should replace the camshaft sprocket with a cast one as ones like yours have been known to disintegrate. They also have a better mark for TDC. There's a thread somewhere with pictures of what can happen.

[amcink]

So i read in other threads that if you have not taken the spark plugs out, therefore the camshaft and crankchaft cannot move (and they have not moved) therefore no need to align both to TDC, and belt already out then just replace the belt as it came out and you should be ok. How true is this scenario?

[OnMy2ndE30]

So i read in other threads that if you have not taken the spark plugs out, therefore the camshaft and crankchaft cannot move (and they have not moved) therefore no need to align both to TDC, and belt already out then just replace the belt as it came out and you should be ok. How true is this scenario?

As long as you rotate the engine by hand after replacement and verify that nothing is hitting, you may be ok. I just don't trust not having any marks to go by. The timing can be a tooth off and not hurt the motor, but it will suffer performance wise. ALWAYS a good idea to verify timing marks before and after......

[amcink]

got it all figure out; thansk everyone

[Click]

Also you have the old style stamped steel timing sprocket which is known to explode occasionally. I would change to a solid metal one while you're in there.

[paperplane94]

^Is that the sprocket!?

[Click]

Yeah, intermediate can go bad too

http://www.r3vlimited.com/board/showthread.php?t=234035

[BergerNJ]

so how can one tell if he has the early or late model m20 in his vert?

I would imagine since I have a 90 but it was built in late 89 that its a late model correct? even though the verts switched to late model styling later on?

Im getting ready to do a head, head gasket, and various other components...starting to see this pop up, might as well change the sprockets as well if I have earlies...