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Distributor repositioning question

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JeffS said:
For all I know, your timing marks are wrong and 10 is actually 4, or something like that.
Click to expand...

At the risk of adding to the mire, I'd like to point out that is unlikely on a TR2-4 motor. Unlike the TR6 (where that problem is rather common), the TR2-4 does not have the pulley mounted on rubber. The mark could be wrong by increments of 60 degrees (due to improper assembly of the pulley/hub), but not by only 6 degrees (unless perhaps the crank key is sheared or the pulley hub is badly damaged). My opinion, if one were to find a timing mark off by a few degrees on a TR2-4 motor, it's time to tear it down and find out why. It probably indicates something about to come apart.
 
poolboy said:
"Without having to pull the distributor" you say ? You could remove it 100 times but unless you alter the "gear position" it's going back the way it came out.
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On a TR2-4, you can rotate the distributor by almost 180 (distributor) degrees, without removing it from the engine.
 
TR3driver said:
poolboy said:
"Without having to pull the distributor" you say ? You could remove it 100 times but unless you alter the "gear position" it's going back the way it came out.
Click to expand...
On a TR2-4, you can rotate the distributor by almost 180 (distributor) degrees, without removing it from the engine.
Click to expand...
I'm not talking about rotating the distributor housing, but I bet you knew that.
 
poolboy,

Of course .... and move it one tooth.

I think it is time to bring this thread to an end... mission accomplished... 14 degrees BTDC achieved. Over and out.
 
Ok, I'll bite, what else causes TR6 timing marks to be wrong?

And Ed was talking about rotating the housing, whatever you were talking about.
 
Randall,

You are right.... I was just talking about and inquiring about rotating the housing. That finally having been accomplished, thanks to you, the car is now performing magnificently..... only not today because there's a freezing rain coming down in western Virginia.. Dommage...
 
LexTR3 said:
I think it is time to bring this thread to an end... mission accomplished... 14 degrees BTDC achieved. Over and out.
Click to expand...

Surely you knew it wouldn't be that easy!!!

(I'm still "dizzy")
 
Ha... ha... What better way to spend a rainy day... Gives me an excuse to put off many other tasks and projects for the moment.

I have to smile because some parts of this thread remind me of what my friends in France used to tellme: Ah... oui... it works in practice ... but will it work in theory."
 
TR3driver said:
Ok, I'll bite, what else causes TR6 timing marks to be wrong?

And Ed was talking about rotating the housing, whatever you were talking about.
Click to expand...
When the timing chain stretches and the "sprockets" wear, the overall effect is that the cam begins to lag behind the rotation of the crank Simply taking up the tension has no effect on the lag. The chain in effect is longer.
In addition the gear engagement between the cam and distributor drive is subject to wear.
A degree here and a couple there as the miles rack up, considering the direction of rotation, damper or crank timing marks overestimate the actual degrees of advance.


Ed seemed to be reluctant to remove the distributor for some reason. Just removing the distributor would not accomplish a thing in this case unless the drive gear were reoriented so that the timing could be adjusted without using up the fine tuning range of the vernier.
It also, as Jeff poited out, risk putting the rotor out of phase with the contacts in the cap.
Ed may never notice the misfire from such though if he is light on the pedal
 
poolboy said:
When the timing chain stretches and the "sprockets" wear, the overall effect is that the cam begins to lag behind the rotation of the crank Simply taking up the tension has no effect on the lag. The chain in effect is longer.
In addition the gear engagement between the cam and distributor drive is subject to wear.
A degree here and a couple there as the miles rack up, considering the direction of rotation, damper or crank timing marks overestimate the actual degrees of advance.
Click to expand...

So the chain would affect the timing of the valves with respect to the crank/pistons, and if left alone, it would of course affect the ignition timing with respect to the crank/pistons. But when you use a timing light, you are setting the timing between the ignition and crank/pistons, right? So you would be compensating for any chain stretch and gear wear (until it stretches/wears again).

I'm not saying that using vacuum to set the ignition isn't a good idea, that's how I did it when I reinstalled the distributor in my TR8, and it resulted in quite a different setting than "by the book", and seems much better.
 
Poolboy,

I'm not reluctant to remove the distributor, as I had to do this to send it to Jeff for rebuilding, but I am reluctant to monkey with the grear below it and the oil pump because I have no experience of this and have read several warnings on the thread to "go slow." Where I sit, if I screw things up with the oil pump mechanism, I'm pretty much up a creek as I'm a long way from a shop that can work on these cars. That's what's behind my reluctance -- just caution.

At present, the vernier is set about half way along its range, a little bit in the direction of Advance. Jeff set it further toward advance than I have it, but I'm pretty close. You are right that I wouldn't know if it is out of phase and wouldn't now how to test it or get it right. I think someone more informed than I am would have to determine that. One test that a friend suggested I performed yesterday: I approached a hill, let the engine lag a bit as I began to climb it, then gave it gas. There was no rattling or pinging or knocking or hesitation. The car just came to life and proceeded briskly up the hill.

I have also examined the rotor of unusual pattern of burn marks.... as I read somewhere. But I'm really in the dark on this

What would you suggest to check if the phasing is correct?
 
You'd have to restore the TDC and cam timing relationship for the timing mart to be valid again.
If you just use a timing light without doing this you are still relying on a timing mark that has gotten to TDC before the cam and distributor, so to speak.
 
Poolboy,

When setting the timing, I always start with the static procedure, making sure that TDC and the cam (with test light) are correct (Is that what you are taling about?). Then, after this is done, I check the timing with an advance timing light and set it 14 degrees BTDC at idle.

Yes... I know that I suggested ending this thread.... but I do want to get this all correct, and the additional information can be of great help to me. Thanks for your patience.
 
poolboy said:
You'd have to restore the TDC and cam timing relationship for the timing mart to be valid again.
If you just use a timing light without doing this you are still relying on a timing mark that has gotten to TDC before the cam and distributor, so to speak.
Click to expand...

I agree on the crank and cam, but the timing light is triggered by the spark, so you are setting the ignition timing in relation to the crank position. In other words, if the timing light indicates the spark is happening at TDC, assuming the mark in the crank is right, then it is at TDC, right?

Now it may be true that with the valve timing off that the optimum ignition timing may be different than specified, and many other factors (such as what we have for fuel these days and any other mods) may change what is optimum.
 
LexTR3 said:
Poolboy,

I'm not reluctant to remove the distributor, as I had to do this to send it to Jeff for rebuilding, but I am reluctant to monkey with the grear below it and the oil pump because I have no experience of this and have read several warnings on the thread to "go slow." Where I sit, if I screw things up with the oil pump mechanism, I'm pretty much up a creek as I'm a long way from a shop that can work on these cars. That's what's behind my reluctance -- just caution.

At present, the vernier is set about half way along its range, a little bit in the direction of Advance. Jeff set it further toward advance than I have it, but I'm pretty close. You are right that I wouldn't know if it is out of phase and wouldn't now how to test it or get it right. I think someone more informed than I am would have to determine that. One test that a friend suggested I performed yesterday: I approached a hill, let the engine lag a bit as I began to climb it, then gave it gas. There was no rattling or pinging or knocking or hesitation. The car just ceme to life and proceeded briskly up the hill.


I have also examined the rotor of unusual pattern of burn marks.... as I read somewhere. But I'm really in the dark on this

What would you suggest to check if the phasing is correct?
Click to expand...
If not reluctant, you sure do sound intimidated about some of this stuff, Ed
You can do a google search on the phasing issue. Look up "Phasing a distributor/ rotor". If you have enough miles on the rotor you may have a look at the scortch marks. If you do have them develope within 1/4 to 1/3 of the total distance from the leading edge, you are probably in phase at the speed at which you normally drive. Of course as the centrifugal advance increases the more the mark moves toward the leading edge. So if you are so reserved in your driving habits and your centrifugal advance never max's out you may be misled. If the day comes that you need some speed to get out of danger or whatever, then you may have misfire and lack the power that you expected
 
Poolboy,

As you can see from my posting, I have looked for the scortch marks, and everthing looks fine. I am reserved in my driving habits, but not all the time. From time to time I open it up to 60-66 and the car just surges ahead... no hesitation. Plenty of power, as far as I can tell.... but mayby I'm missing something...

BTW: I have the Phasing a distributor/rotor and have struggled through it two times, but it's still a bit of a mystery to me. I'll keep working on it.
 
I remember back when I was in High School I had a volvo P1800 with twin SU's I use to get the carbs set get the idle set and then start advancing the distributor, go for a drive, reset the idle, advance the dist, go for a drive, and keep doing this till the engine started pinging under heavy driving load and back off a till it quit pinging, set the idle and I was done, I never had a timing light and never burned anything up looks like we took distributor 101 to quantum physics!

if it runs good, you are happy with the performance, no pinging,I would say you are good to go

but its all good info and thanks for Jeffs post since he rebuilt my dist too

Hondo
 
Poolboy, I assume you mean Jeff's third paragraph. The car did not ping at 15 degrees BTDC (the top of Jeff's suggested range). I realize that what you are saying is that I should keep on advancing it until it pings, and then retard it. As it stands, I have it set at 14 degrees BTDC, which is where Jeff said I probably would get the best performance for my car, my driving, etc., etc.

Jeff did a magnificent job. My only problem was in achieving his specificatons.

It would be hard for me to imagine the car running any better than it is now. Performs like a new car.
 
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