How do you time the M50?

[shiboujin]

I read up on a few books but they are all vanos specific. I took the cams off once to do some head work. I don't have the bmw specific tool to make sure your cams are EXACTLY TDC but its very close. The bottom end is also lined up right. Now the cam gears and the cam to crank timing gear can be rotated a bit and tightened down but how do I know what the right place is without starting her up and getting a timing light out?

[equate975]

YOu ahve to linbe it all up like it should be, there is not adjusments. Get the tool ans dont doit

[FredK]

^lol.

Um, I believe the procedure is essentially the same for the NV, as the cam to crank gear is also slotted on the TU, as are the cam gears. You set the crank gear first, arrow pointing up, 3 bolt holes all the way to the left (while facing the engine), insert dummy tensioner, then install cam gears with the bolt holes both exactly centered, with both arrows pointing up.

At least, this is what makes sense to me. If you don't have cam blocks, use a straightedge on them at the very least. It's hard to eyeball them!

NV owners, feel free to correct me if I'm wrong. I've only dealt with the TU.

[Jason89i]

your right fred. however, i would not use a straight edge. use the cam locking block and set them "straight up". almost exactly the same as the tu motors. cheers, jason

[shiboujin]

So it should just be centered? Doesnt sound very exact to me but ok. I might try the straight edge. Depends though. how much does the lock tool cost?

[matt]

"real close" generally costs between 4 and 40whp at the peak and a TON of torque vs "just right"

[shiboujin]

"real close" generally costs between 4 and 40whp at the peak and a TON of torque vs "just right"

which is why I want it done right. It doesnt make sense to just get it "in the center of that hole thing" On the M20 you just line up the marks. Only 1 cam to worry about tho.

[hoveringuy]

I made my own cam locking tool and it worked fine. The factory tool is always the best but if you aren't an idiot with the straight edge and can lock the cams you'll be Ok. Keep in mind, the cams will move as you tighten the sprocket so they will need to be locked somehow.

[shiboujin]

Sounds good to me!

[static]

personally, i've invested $60 in a good set of cam blocks and fly pin (didn't use pin) from ebay
I've noticed that the square looking cam ends are not actually square (i.e even tho blocks make them perfectly perpendicular to the head edge, the other sides didn't look parallel as they would if the ends were square) in light of this, i wouldn't use a straight edge or, even worse, just eyeball them

also, you can't check cam timing with a timing light (it's for ignition timing). And, no, starting it is not the best way to ensure you got it right. (as these are interference engines)

[318isbmw]

also, you can't check cam timing with a timing light (it's for ignition timing). And, no, starting it is not the best way to ensure you got it right. (as these are interference engines)

Also can't use a timing light because it has no plug wires to get the signal out of, nor the timing markers for doing that on the front of the motor.
I'd go and buy the tool. It never hurts to add another tool to your collection and the price of the tool is much less than fixing the motor if its not right.

[static]

Also can't use a timing light because it has no plug wires to get the signal out of, nor the timing markers for doing that on the front of the motor.
I'd go and buy the tool. It never hurts to add another tool to your collection and the price of the tool is much less than fixing the motor if its not right.

not many people know this, but you CAN use a regular timing light on these engines (i did)

[matt]

not many people know this, but you CAN use a regular timing light on these engines (i did)

We do regularly also.

[e30serg]

Care to elaborate? I take it the light was used AFTER you were certain the timing was pretty close? Getting it really off and starting the engine sounds like a bad idea.

I remember having to plug the distributor advance vacuum line on my old car when timing it. How was this taken care of on the s52's? I know it doesn't have an actual distributor....

[EtaSport]

Make sure you spin the engine over a few times and verify. I had a car come in the shop that had a head replacement done at a tire shop and they were complaining of rough idle. I popped the cover off and found both cams a tooth off.