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No Vacuum: Initial timing at beginning (read only) should be somewhere around 8 degrees BTDC. Doesn't really matter.
At 3500 rpm Total timing should be at 36 degrees. If not adjust the distributor until it is. This is the one that matters.
Once it is rock steady at 36 degrees at 3500, experiment with the rpm a little. A little higher, a little lower. If it changes tell us. If timing goes higher than 36 Do Not Drive it!
As you slowly drop the rpm from 3500 at some point the timing should start to drop from 36, tell us what that rpm is.
Then go re-read the timing at idle, do not change it, just tell us what it is.
Still no vacuum.
Report back.
Vacuum is the last step and you must get all the above correct first.
Last edited by leigh1322; May 4, 2021 at 04:27 PM.
[QUOTE=lionelhutz;1603400357]Here's a simple rule - Use the adjustment on the light to get the timing mark to be at 0* OR leave the light set to 0* and read degrees from the timing tab. Never mix both methods.
Do this:
1. Disconnect the vacuum advance and plug it.
DONE
2. Hold the rpm at 3500rpm and adjust the light until the timing mark is at 0*. Take the reading on the timing light.
20 DEGREES
3. Drop it back to idle. Adjust the timing light until the timing mark is at 0*. Take the reading on the timing light.
0 DEGREES
4. Plug in the vacuum advance. Adjust the timing light until the timing mark is at 0*. Take the reading on the timing light.
19 DEGREES
DOES THIS SOUND RIGHT BEFORE I CONTINUE. Caps so you see my response
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Your timing light is broke or you don't know how to use it. The '400' number is engine rpm. I doubt the engine can idle at 400 rpm. And you can't have 19* initial advance at 0 rpm i.e. the engine has stopped. Same deal with vacuum advance at 400 rpm i.e. engine can't idle that low. Go back and do what Bikespace says. But set your idle speed to 800 rpm before you start. That said, 20* mechanical is probably correct. !9* vacuum advance is probably correct. 0* initial might be correct but is WAY off. What you want is 36* total advance (mechanical + initial) at 3500 rpm (it should really be 3000 rpm). That will give you 16* initial at 800 rpm and 0* mechanical at 800. Verify like Bikespace said. AND FORGET ABOUT VACUUM ADVANCE AT THIS STAGE!!!! Plug the port where the vacuum hose is connected, either at the carb or on the manifold. Just make sure its plugged. We'll come back to the vacuum advance after you set your total timing to 36* at 3500 rpm.
Your timing light is broke or you don't know how to use it. The '400' number is engine rpm. I doubt the engine can idle at 400 rpm. And you can't have 19* initial advance at 0 rpm i.e. the engine has stopped. Same deal with vacuum advance at 400 rpm i.e. engine can't idle that low. Go back and do what Bikespace says. But set your idle speed to 800 rpm before you start. That said, 20* mechanical is probably correct. !9* vacuum advance is probably correct. 0* initial might be correct but is WAY off. What you want is 36* total advance (mechanical + initial) at 3500 rpm (it should really be 3000 rpm). That will give you 16* initial at 800 rpm and 0* mechanical at 800. Verify like Bikespace said. AND FORGET ABOUT VACUUM ADVANCE AT THIS STAGE!!!! Plug the port where the vacuum hose is connected, either at the carb or on the manifold. Just make sure its plugged. We'll come back to the vacuum advance after you set your total timing to 36* at 3500 rpm.
Well let me redo it.
as an FYI after I did all steps I ended at 560rpm when I set the dial to 36 my timing mark is at zero on idle with vac connected. Let me start again at higher idle
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Originally Posted by michael lamoglia
[
sorry for the delay neighbor showed up with beer he thought I needed one hearing me rev this thing. I kicked him out. Here we go:
forget the zero I had turned the car off at that point but forgot to take the pic. My bad.
so I REDID it all. Forget vac advance. Here we go.
A. set idle to 800rpm
b. No vac connected, held idle at 3600 and had to set my gun to 22 to get the timing mark to zero. (Close to wha to had before) [b]So that gives you 22* mechanical advance and 0* initial. OK.
c. Dropped it back to idle. Had to set gun to zero degrees to get timing Mark to zero. So that confirms 0* initial.
d. Skipped plugging in advance Good.
e. Held rpm to 3600 and set timing light to 36. Moved dizzy till it got to zero. OK, that gives you 14* initial and 22* mechanical. Good.
f. As an FYI back to idle timing mark is on zero. Idle goes from 630 when starting to 700. NO VAC. Not good. You should see the 0* mark on the timing tab when your timing light is set to 14*.
See bold but I know you know that.
Edit: I'm assuming that you have springs in your dist'r that are heavy enough to prevent any mechanical advance at your idle speed.
Last edited by resdoggie; May 4, 2021 at 08:04 PM.
FORGET the last part don’t know what the hell I got that from but yes 14 degrees at zero!!!!! Yes!!!!!! What’s next
That makes more sense!
So we have
800 14
900 14
...
3500 36
So you have 22 degrees of mechanical advance in your distributor (assuming it doesn't keep going up).
First: Figure out what RPM is "all-in", so at what RPM you hit 36 degrees advanced. Go up high, too, to make sure it doesn't keep climbing.
Second: At idle, plug in the vacuum advance. I think you have 19 degrees of vacuum advance (too much!), and your initial will jump from 14 to 33. But then we will know.
Now we are getting somewhere.
14 initial (idle)
22 mechanical advance
36 total at 3500
Now verify the idle and 3500 numbers and lock the distrib down. That part is set.
Please rev it to 36 degrees at 3500 and then slowly back down until the advance starts to drop and let us know the rpm.
Also go to 3500 and go up some and see if the advance climbs.
I hope not.
Car should run great now at 1/2 throttle and up.
Not so much at idle and light throttle.
Next step is the vacuum.
If you really have another 19 degrees with the vac connected, it will be too much. Common problem with a performance curve.
You probably only want about another 12 degrees with the vac. Verify what it gives up (idle only) with vac on / then off.
We'll tell you where to get a limiter to limit the vac advance later.
If you leave it at 19 more on vac it will probably rattle/ping like mad. Not good.
So you have 22 degrees of mechanical advance in your distributor (assuming it doesn't keep going up).
First: Figure out what RPM is "all-in", so at what RPM you hit 36 degrees advanced. Go up high, too, to make sure it doesn't keep climbing.
Idle doesn’t go past 900 BEFORE vac advance. I rev it to 3550-3600 ish to get it to 36 degrees advanced
Second: At idle, plug in the vacuum advance. I think you have 19 degrees of vacuum advance (too much!), and your initial will jump from 14 to 33. But then we will know.
when I plug in manifold vac, I have to set timing light to 36 to get the timing mark to zero.
You can do this which verifies your distributor is working. You don't have to, but it will check the mechanical advance is working.
- Set the gun to 14* and increase the rpm until the timing mark starts to move advanced, Note that rpm.
- Keep increasing the rpm in about 500rpm steps and measure the timing at each rpm. Remember, adjust the light until the timing mark is at 0*. Record the rpm and the timing degrees for each step.
- Stop doing the above step when the timing quits increasing. Hopefully by about 3500rpm it quits increasing.
- Let it go back to idle and double check that the timing is still 14*.
Now to address your vacuum advance.
At idle
- Plug in the vacuum advance and measure the timing. What is it?
- Unplug the vacuum advance and check that the timing is 14* again.
- Plug in the vacuum advance again and measure the timing. You should get the same result as the first time.
If the above checks out then your vacuum advance is working. Next step might be to adjust it if it's now working right.
Now we are getting somewhere.
14 initial (idle)
22 mechanical advance
36 total at 3500
Now verify the idle and 3500 numbers and lock the distrib down. That part is set.
Please rev it to 36 degrees at 3500 and then slowly back down until the advance starts to drop and let us know the rpm.
the advance doesn’t start dropping
till about 900rpm ish.
Also go to 3500 and go up some and see if the advance climbs.
I hope not.
Doesn’t climb!
Car should run great now at 1/2 throttle and up.
Not so much at idle and light throttle.
Next step is the vacuum.
If you really have another 19 degrees with the vac connected, it will be too much. Common problem with a performance curve.
You probably only want about another 12 degrees with the vac. Verify what it gives up (idle only) with vac on / then off.
We'll tell you where to get a limiter to limit the vac advance later.
If you leave it at 19 more on vac it will probably rattle/ping like mad. Not good.
You can do this which verifies your distributor is working. You don't have to, but it will check the mechanical advance is working.
- Set the gun to 14* and increase the rpm until the timing mark starts to move advanced, Note that rpm.
- Keep increasing the rpm in about 500rpm steps and measure the timing at each rpm. Remember, adjust the light until the timing mark is at 0*. Record the rpm and the timing degrees for each step.
- Stop doing the above step when the timing quits increasing. Hopefully by about 3500rpm it quits increasing.
- Let it go back to idle and double check that the timing is still 14*.
Now to address your vacuum advance.
At idle
- Plug in the vacuum advance and measure the timing. What is it?
36degrees on timing light
- Unplug the vacuum advance and check that the timing is 14* again.
It’s at 14 degrees
- Plug in the vacuum advance again and measure the timing. You should get the same result as the first time.
36 degrees
If the above checks out then your vacuum advance is working. Next step might be to adjust it if it's now working right.
