Quick question on timing

Speedfreak

Speedfreak

Active Member
My Distributor arrives back with me tomorrow, having been rebuilt, and I have a timing light in order to get my timing as accurate as possible. I think this might be a bit of a daft question, but which spark plug lead do I use I’ve been given two different opinions. One person told me it was the spark plug closest to the radiator(front), and another source tells me it’s the spark plug closest to the bulkhead, now I’m very confused, so if any kind kind sold knows the answer I would be most grateful.
 
Getting the timing as accurate as possible according to what...?
Setting as accurate as possible according to the timing marks, only satisfies one thing - the owner's OCD! Timing marks are largely irrelevant these days, as the combustion characteristics of modern fuel is markedly different from the petrol of the period. It combusts slower, for a start, so you need more advance, but the shape of the optimum advance curve will also be different - steeper primary (ie faster advance). So the only way to get it as accurate as possible relative to the fuel combustion characteristics is to have the car set up on a rolling road.

Outside of that, the best way to get reasonable success is to start with the factory timing setting and gradually advance until the engine gains speed at idle. Just at the point it begins to lose revs again, twist it back a fraction and tighten it up. Take it for a test drive, and fettle from there. It's all trial and error from there. The original timing marks assume the fuel combustion rate is a constant, and it has since varied over the decades.
 
Hello,

I’ve also been experimenting with the timing, reason was changing the distributor with an electronic one.
8-9 degrees advances works well in my case.

“Just at the point it begins to lose revs again, twist it back a fraction and tighten it up”
This part I do not understand, if I turn the distributor to advance the timing the revs only increases, so how can it decrease ?

Thanks,
Wilfred
Ignition P6.jpg

 
Help! What have I done wrong? I have refitted my Distributor and I can barely get the car to start.

When the car does fire up, she is as rough as old boots, I’ve turned the Distributor, which helps a little, but still something is clearly wrong. I have read it is possible to be 180° out, however how is this possible as the gear at the bottom of the distributor is off set? Have I lost the plot?
 
Hmmm,

So I did, the engine’s rpm is now about 800-900, not entirely stable though. But, it drives well and the starter motor only needs a short turn to start up the engine.

Wilfred
 
No worries whatsoever it helps us all to learn more…I’m just fed up at my lack of knowledge and mechanical skills.
 
You can reinstall the dissy one gear tooth out which makes it hard to get the timing right (the vacuum advance hits something). Could be you did that by accident?
 
I guess that is possible…..no idea how though? Whilst my dizzy was being re built I didn’t touch the engine and I thought I’d put back as it was….?
 
Speedfreak said:
I guess that is possible…..no idea how though? Whilst my dizzy was being re built I didn’t touch the engine and I thought I’d put back as it was….?
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When taking things like the dist apart, or from an engine STOP ! Take photos ! In this case remove the cap and photo the location of the body, and the location of the rotor arm, if you do not have a timing light this will enable reassembly.
As sdibbers has said, you may have the body in the right place, but with a drive that has a skew gear the rotor arm can be anywhere, you need to probably start again..
Check the timing marks are visible on the engine, remove the spark plugs, put a thumb or finger in number 1 plug hole, turn the engine over slowly with a socket on the crank pulley bolt, feel for compression building in No 1 cylinder.
Turn until you get to just before TDC, STOP.
Put the dist in so the body is in a good place for adjustment and the rotor arm is just about pointing to the segment in the cap that has No1 plug lead on it, check rotation of distributor and make sure the rotor arm is just BEFORE No1 lead segment.
Car should run, time ignition with strobe light.
 
cobraboy said:
When taking things like the dist apart, or from an engine STOP ! Take photos ! In this case remove the cap and photo the location of the body, and the location of the rotor arm, if you do not have a timing light this will enable reassembly.
As sdibbers has said, you may have the body in the right place, but with a drive that has a skew gear the rotor arm can be anywhere, you need to probably start again..
Check the timing marks are visible on the engine, remove the spark plugs, put a thumb or finger in number 1 plug hole, turn the engine over slowly with a socket on the crank pulley bolt, feel for compression building in No 1 cylinder.
Turn until you get to just before TDC, STOP.
Put the dist in so the body is in a good place for adjustment and the rotor arm is just about pointing to the segment in the cap that has No1 plug lead on it, check rotation of distributor and make sure the rotor arm is just BEFORE No1 lead segment.
Car should run, time ignition with strobe light.
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Thanks for the advice. I have followed everything you said to the letter and sadly no improvement….. it will run, but it’s very rough and there is a rise and fall in the tick-over. However, any adjustment I make to the Distributor to try and make things better the engine just stalls. I’m beginning to wonder if I have issues elsewhere, but having had the carburettor completely rebuilt, I’m starting to get a little confused.
,
 
Ok, a quick step back here. A few questions for you:

(1) Did the engine run fine before removing and replacing the distributor?
(2) If yes to (1) did you do anything else to the engine or related systems?
(3) Have you checked ignition timing with a light when running? If so, what was the advance noted? A good starting point for TC’s with modern fuel seems to be around 4° - 8° BTDC

Get back to us with answers for above and let’s see if we can help you track down the issue.
 
sdibbers said:
Ok, a quick step back here. A few questions for you:

(1) Did the engine run fine before removing and replacing the distributor?
(2) If yes to (1) did you do anything else to the engine or related systems?
(3) Have you checked ignition timing with a light when running? If so, what was the advance noted? A good starting point for TC’s with modern fuel seems to be around 4° - 8° BTDC

Get back to us with answers for above and let’s see if we can help you track down the issue.
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Hi Sdibbers, okay here we go….

1 The engine was running pretty well, except I had fluctuating tick-over and a lack of power up hill, there issues I put down to the fact that the Distributor was in need of a service. The vacuume was Locked solid however , it did run and drive okay-ish.
2 I didn’t touch anything on the car in between removing the distributor, and then refitting it following its refurbish.

3 when I put a timing light on it, I have one of those guns with a dial that you turn. In order to get TDC in line with the little arrow pointer, I have to turn the dial all the way round to 50 or 60°. I know that last bit sounds completely mad another way.
many thanks for your time to look at this. I have been messing around with it all day and I have got absolutely nowhere
 
Just wondering, you mentioned a rebuilt of your dizzy, so I guess the position of the part I circled red could be misaligned and the timing way out of what it should be.
You can rotate them relative to each other, so much more than the fine tuning.

IMG_0905.jpeg
 
sdibbers said:
You can reinstall the dissy one gear tooth out which makes it hard to get the timing right (the vacuum advance hits something). Could be you did that by accident?
Click to expand...
to answer this question, my Distributor is located with offset lugs, Therefore, I don’t see how it can be out?
 
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