Weird Timing Anomally
 

Here's weird problem I'm having at the moment:

It appears that when my distributor should be advancing the engine it (according to my timing light) is actually retarding it!

I have converted a 2.4 T bosch distributor to fit my ex-Marelli 2.2 T. It has a vacuum unit on it which I have not blanked or attached to anything as I assumed it does nothing on my engine? I know for a fact that I have incorrect springs on the centrifical advance unit (as I am planning to send it away for a re-graph) but this shouldn't retard the engine should it?

Cheers

No, it shouldn't. I hope you will not be insulted as I ask whether your timing is moving to the right or to the left. On my car, the crank pulley turns clockwise, so when ignition is advancing, the TDC mark appears to move to the left, not the right. It would seem to me nearly impossible for the centrifugal advance to move backwards. It should either advance, or do nothing (if it were frozen).

I may be way off, but when I looked at the points from my old 72S they are mirror images of those for my 70E, but I cant remember if the distributor was clockwise or CCW. I think the later cars went CCW, could this be your problem??

remember guys, Fishcop is "down under", where the toilets flush the other direction.....

Maybe crankshafts turn the other direction as well...;)

Just a little humor..............

all distributors up to and including 77 turn the same direction. clockwise. so yours will be fine.

Okay Fellas, here's what I'm seeing....I can perhaps load up a picture if I'm not being clear on my description.

With the engine idling and timing light functioning I've set the timing on the first mark (Z1), I'm assuming the mark just next to it on the LEFT is 5 degrees btdc. Further around to the LEFT of Z1 I see another mark that I'm assuming is 35 degrees btdc?

When I rev the car up to between 4000 and 6000 rpm, it appears that the crank pulley turns to the LEFT under the timing light with all the marks turning away to the LEFT from the fan mark. I can see no other marks.

So what have I done wrong?

This may help: If there were a timing mark just to the left of my Z1 mark, it would represent 5 degrees AFTER TDC. In fact, there is a mark just to the right of my Z1 mark, and it is 5 degrees BTDC. My crankshaft turns clockwise.

Which may be counterclockwise in the southern hemisphere, I just don't know.

Pulley rotates clockwise. The mark to the left of Z1 is 5 deg ATDC. You can remember this by visualizing the pulley rotating in your head - the 5 deg mark passes 12 o'clock after Z1. On my pulley there are marks for 30 and 35 deg BTDC to the <b>right</b> of Z1, and this is the direction the distributor will advance towards as RPMs are increased.

Thanks Jeff and Superman, you are helping :) ......But I was sure when I watched my mechanic time my engine a few months ago, that as the engine reached 6000rpm another mark lined up on the fan mark...ie- 35 degrees BTDC What is the point of the current mark on my pulley being approximately 35 degrees ATDC?

I dunno. There are three TDC marks on your pulley, or at least on mine, about 120 degrees apart. 35 degrees would be less than two inches, I think. And it would appear to the right of the Z1 mark, as you know.

John

Sorry to jump on your thread... how is the car running anyway?

I was after more info on the Top Gun ignition wires - where did you get them from?

Cheers!

Cam

a mark to the left of Z1 is probably the MFI pump timing mark. was your car MFI? it would have a FE on the face of the pulley.

I agree with John. That is the FE mark. If you examine closely you will see the letters next to the mark. I think there are also some other random marks on the pulley that are there to confuse you. :)

Okay guys, thanks. I'll ignore the other marks (who knows what pulley is on the engine after 33 years! I'm pretty sure the engine has never had MFI but....?)

I own a dial-in timing light, so I'll set it up using that feature.

Cam, the Top Gun ignition leads are excellent and plug straight in. I did however trim the excess spiral wire left exposed at the crimps. As I still don't have perfect timing (sending the dizzy away to Scorcher Distributors in Melbourne for a re-graph) I can't give a definitive answer yet!

Thanks everyone

Thanks John - I have ordered myself a set. I might even get them tomorrow.

Cam