11 replies to this topic

[HUBBA.HUBBA]

Surely if it is near dot to dot its inthe right ball park?

[Sam Walters]

You cant get it 180 out....Although dot to dot could be as much as 10.

[HUBBA.HUBBA]

That's reassuring. I'm sure I read some where on here that some one had it 180 degrees out as their mechanic had put it on the wrong way?!

[MRA]

In the right ball park you say.....

However it really needs to be in the right goal on said ball park.

If it is a standard uncut rover item lining up the dots should be suffice, if it has been recut it could be a long way out depending on what it started as and what it has been cut to.

[jaydee]

That's reassuring. I'm sure I read some where on here that some one had it 180 degrees out as their mechanic had put it on the wrong way?!

That was probably the dizzy drive, you cant fit a camshaft 180° out.

[HUBBA.HUBBA]

That's reassuring. I'm sure I read some where on here that some one had it 180 degrees out as their mechanic had put it on the wrong way?!

That was probably the dizzy drive, you cant fit a camshaft 180° out.

I actually think its the dizzy drive in the wrong postition that is stopping my car from starting after rebuild.

[MRA]

You can't actually fit the dizzy drive 180 degrees out, this is because the gear has an odd gear tooth count, I have found that there is a distributor remanufacturer than doesn't know how to build dizzy's and they end up being 180 degrees out, to correct for this once all else is correct simply undo the 2 screws holding the dizzy base plate (this is under the points, remove the distributor cap to find it) and turn it through 180 degrees.

Ok to repeat myself..... If the camshaft is an aftermarket or reground camshaft it can very easily be a mile out !!! and you must time it in correctly using the figures from the company who modified it.

This is even true for a standard camshaft that has been reground to recondition it.

[MRA]

It is actually possible to fit the camshaft at any angle out of position..... as all you need to do is put the chain on incorrectly.

[jaydee]

The dizzy drive will fit 180° out..

[MRA]

Jaydee I understand why you say that it can however please let me clarify, to fit the distributor drive 180 degrees out it would have to have an even quantity of gear teeth, it hasn't. Therefore it cannot possibly be installed 180 degrees out, it can however be installed almost 180 degrees out,

It has 7 teeth (from memory) therefore 360/7 =51.429 degrees

The drive will be out by 1/2 this amount namely 25.715

Installing the distributor drive in either 1 of 2 places namely.......

1) 154.285
or
2) 205.715

Neither of which are 180 degrees and the main reason why so many of you have HT leads that look like half are too short whilst the other half are too long.

Edited by mra-minis.co.uk, 03 February 2013 - 11:53 PM.
Math error

[jaydee]

Yeah i now get what you mean, but why wont 3rd place be 154.285°?

[MRA]

Im going to take another look at my math, in theory its correct, the numbers maybe slightly out though, I will get back you on this, unless someone else beats me to it

Jaydee you are correct, I have modified my post above to the updated values.

Edited by mra-minis.co.uk, 03 February 2013 - 11:53 PM.