Crank pulley markings

[John L]

I have the TDC mark on my crankshaft pulley, but none of the graduations either side.

Would it be possible for any of you guys who have a pulley off their engine, to measure from the TDC mark to 5, 10, 15 degress, and give a measurement in MM please. I will transfer to my pulley.

I can not measure the diameter accurately as the pulley is still on the car, and the fan hub gets in the way. If I had that I guess I could work out the degrees also.

 

Regards John

[Yorkkie]

I have the TDC mark on my crankshaft pulley, but none of the graduations either side.

Would it be possible for any of you guys who have a pulley off their engine, to measure from the TDC mark to 5, 10, 15 degress, and give a measurement in MM please. I will transfer to my pulley.

I can not measure the diameter accurately as the pulley is still on the car, and the fan hub gets in the way. If I had that I guess I could work out the degrees also.

 

Regards John

 

 

 

You can measure the diameter and Circ=Pi*D

 

D/360 gives you MM/Deg..... I am sure someone has done this and posted before.

 

Regards

Andy

[88V8]

With an advance timing light you only need TDC

http://www.thetoolac...p?productId=743

Also pre-owned on eBay, but not atm.

 

I believe Halfords do something similar for less money.

 

Ivor

[rpurchon]

I have the TDC mark on my crankshaft pulley, but none of the graduations either side.

Would it be possible for any of you guys who have a pulley off their engine, to measure from the TDC mark to 5, 10, 15 degress, and give a measurement in MM please. I will transfer to my pulley.

I can not measure the diameter accurately as the pulley is still on the car, and the fan hub gets in the way. If I had that I guess I could work out the degrees also.

 

Regards John

 

strange you have no timing marks unless they are painted over.

or you have a odd pully fitted which could be different to normal ones.

wrap a strip of paper around the pully and mark the lenght.[example 650 mm]

divide the lenght by 360.= 1.805mm.=1 degree x5 = 9.025 so 5 degrees would be 9mm etc.

for a cheap timing light try these,induction pick, had mine 4 years no problems

http://www.rdgtools.co.uk/acatalog/info_892375.html £17.

and it wont hurt your wallet as much when it gets eaten by the fan.

richard

[poolboy]

According to my damper and measurements, 4 degrees = 6mm.

My damper is hash marked in 2 degree increments and number stamped in 4 degree increments.

Edited October 6, 2010 by poolboy

[88V8]

There are at least two pulleys - outside diameter 6.5" and 5.875".

 

Ivor

[poolboy]

....I knew I should have posted that. This particular damper is 6.5in in diameter.

Edited October 6, 2010 by poolboy

[John L]

Thanks guys, I have a simple timing light, so it doesnt have the luxury of the advance adjustment.

I must say I hadnt thought of wrapping a piece of paper around the diameter, its nice to have suggestions/alternative ways of doing things!!

I have rubbed either side of the tdc mark but nothing appears, will mark it with a chisel perminantly whe I've done the maths.

Thanks John

[Yorkkie]

As I am a bear of small brain. I keep confusing myself with the timing marks on my pulley.....

 

I have a solid line across the edge of the pulley that looks to coincide with TDC. If i was to mark a line on the pulley edge to become coincident with the fixed marker when timing it using a simple strobe, would it be to the left or the right of the TDC mark looking down from the front of the car?

 

I think that it should be to the right of the TDC mark as this is a point BTDC in a clockwise rotation of the crank.... and what should this be at tickover (11 deg BTDC)?

 

 

Please can someone dispell my confusion.

 

Andy

 

 

[poolboy]

I can supply this picture:

[John L]

Yorkkie

Looking from the front of the car with the engine running the 11 degrees want to be on the right of the TDC mark, as you rightly say the degrees are before the TDC mark, in a clockwise rotation.

But it is well worth spending a little time to find the actual TDC of #1 piston, by taking out the plug, and finding the highest movement of the piston with a screwdriver in the plug hole, by turning the crankshaft, then remark the pulley as being the correct TDC position, and then adding or subtracting any degrees from the original TDC mark to the prescribed timing position BTDC.

Hope that hasnt confused the issue more?

 

Regards John

[Yorkkie]

Yorkkie

Looking from the front of the car with the engine running the 11 degrees want to be on the right of the TDC mark, as you rightly say the degrees are before the TDC mark, in a clockwise rotation.

But it is well worth spending a little time to find the actual TDC of #1 piston, by taking out the plug, and finding the highest movement of the piston with a screwdriver in the plug hole, by turning the crankshaft, then remark the pulley as being the correct TDC position, and then adding or subtracting any degrees from the original TDC mark to the prescribed timing position BTDC.

Hope that hasnt confused the issue more?

 

Regards John

 

 

 

Thanks, the picture from Poolboy and your comments are very helpful.

 

cheers Andy

[john.r.davies]

A coat of matt black paint, clean out the markings with a sharp point and then paint them with white paint. No need for microscopic accuracy, just file the excess paint off afterwards with a fine file. Makes the graduations much easier to read.

 

See pic, which shows a pulley done thus that has been well used, to show that the treatment doesn't rub off.

 

John

Edited October 9, 2010 by john.r.davies

[dobby]

Hello, I am new to TR and have an ex US 1976 CF model on SU carbs. I was looking through the notes and it says the timing should be 4 deg after TDC??

 

I have just fitted a pertronix igniter and the best running I get is 11 degrees, she is really smooth and no pinking. At 4 degrees its ok but "hunts" a bit and I would say less responsive.

 

Can I just check... ref the picture of the pully, looking from the front of the car... TDC was to the left of the pointer and the pointer was on 11 degrees?

 

Some feedback on the igniter... I would highly recomened it. A noticable differance to pints and condenser, allot smoother, sounds better and I would say it feels more torquey.

 

Cheers

 

Doug

Edited June 26, 2011 by dobby

[poolboy]

Hello, I am new to TR and have an ex US 1976 CF model on SU carbs. I was looking through the notes and it says the timing should be 4 deg after TDC??

 

I have just fitted a pertronix igniter and the best running I get is 11 degrees, she is really smooth and no pinking. At 4 degrees its ok but "hunts" a bit and I would say less responsive.

 

Can I just check... ref the picture of the pully, looking from the front of the car... TDC was to the left of the pointer and the pointer was on 11 degrees?

 

Some feedback on the igniter... I would highly recomened it. A noticable differance to pints and condenser, allot smoother, sounds better and I would say it feels more torquey.

 

Cheers

 

Doug

 

I don't recommend relying on the damper marks to retain their accuracy. They may be as much as a degree (less than reality) per 20k miles since the engine was new,

But if you look at the picture I submitted, you'll see that the side with the greater number of degree marks is the BTDC side.

For finding your engines true 'sweet spot' as far as ignition timing is concerned , you can't beat this. http://automotivemileposts.com/garage/v2n8.html

Just use the nipple on the intake manifold's banjo fitting for the Anti Run on Valve to connect the Vacuum Gauge. The nipple will probably be capped off and unused since the SU carbs have no provision for the Anti Run-on feature anyway