Distributor Vacuum Advance
Thread Starter
Racer
Joined: Jun 2007
Posts: 272
Likes: 1
Distributor Vacuum Advance
I have a stock 327 in a 62 with correct intake manifold. The problem is the vacuum advance canister hits the manifold and can not correctly time the engine. Yes, it runs but I have way too much advance, like way past the marks.
Hopfully here is a picture. Are the different shape advances?
Thanks,
Bob
Hopfully here is a picture. Are the different shape advances?
Thanks,
Bob
Le Mans Master
Joined: Dec 2007
Posts: 8,000
Likes: 659
From: Puget Sound
Are you disconnecting the vacuum advance when checking the timing? Your pic. shows that the interference is preventing you from advancing the timing further. If you still have a problem, just move all your plug wires 1 position counter clockwise. The #1 plug wire should be directly above the point adjustment window. Yours is not.
Jim
Jim
Last edited by 1snake; Apr 5, 2012 at 10:30 AM.
Le Mans Master
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From: Puget Sound
Team Owner
Joined: Jul 2006
Posts: 22,131
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From: Kannapolis NC
Here's a picture of a 62 to show you what I mean by yours looks low. If it's a matter of rotation only, you can do as stated and move the wires a space each to change the rotation set point
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
What's your current base timing set at with the vacuum advance disconnected and plugged and the distributor in the position shown in your photo?
Correct wire indexing in the cap will have the #1 wire in the next cap tower clockwise from the adjustment window, not the one above it.
Correct wire indexing in the cap will have the #1 wire in the next cap tower clockwise from the adjustment window, not the one above it.
Le Mans Master
Joined: Dec 2007
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From: Puget Sound
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,873
From: Greenville, Indiana
I have a stock 327 in a 62 with correct intake manifold. The problem is the vacuum advance canister hits the manifold and can not correctly time the engine. Yes, it runs but I have way too much advance, like way past the marks.
Hopfully here is a picture. Are the different shape advances?
Thanks,
Bob
Hopfully here is a picture. Are the different shape advances?
Thanks,
Bob
If you re-index the wires to correct, your timing will further advance so you need to reset the gear mesh on the camshaft.
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Le Mans Master
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St. Jude Donor '10-'12-'13
Le Mans Master
Joined: Dec 2007
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From: Puget Sound
No. Just lift the dist. up enough to disengage it from the cam gear and turn the rotor 1 or 2 teeth the direction you want. The dist. won't drop all the way back down (not engage with the oil pump drive) but when you turn the motor over a little, it will.
Jim
Pro
Joined: Dec 2008
Posts: 520
Likes: 20
From: Horseheads NY
Start from scratch,pull dist stuff number1 hole with tissue bump it over until the tissue flys out,check you timing mark on balancer and turn it with a ratchet
Until timing mark is at 0. Redrop dist,bump it over a few times and
It will drop into oil pump shaft. Make sure rotor is at about 6:30 when you drop it,plug vacuum hose when you disconnect from advance and retime
Until timing mark is at 0. Redrop dist,bump it over a few times and
It will drop into oil pump shaft. Make sure rotor is at about 6:30 when you drop it,plug vacuum hose when you disconnect from advance and retime
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
It may still not be possible to set the timing and in that case, the OP will have to turn the gear a half turn on the distributor shaft and reseat the distributor. This might explain why the cap is wired wrong, if it really is.
Pro
Joined: Aug 2010
Posts: 578
Likes: 11
also here's a picture of my '62 327 and the vacuum advance...looks like it's a little to the right of where yours is located.
Thread Starter
Racer
Joined: Jun 2007
Posts: 272
Likes: 1
OK guys, let me try to sum up everyone's input and what I need to do or have done:
1. Plug wires need to be repositioned 1 hole clockwise.
2. Distributor needs to be re-indexed with cam and oil pump
3. Engine needs to be retimed.
Someone asked what my degrees of advance. I do not know but the mark on the dampener is well beyond the farthest mark on the indicator, at least twice the distance between the 0 and the most advance mark.
So what affect(s) does being this far out of time have on the engine? Once everything is to spec, will this have any affect on either performance and/or fuel mileage? The engine is a stock 327/300HP with powerglide. I usually only put enough gas in for the day's drive but estimate I get 10/12 MPG.
I am not sure I am up to making the adjustments of the distributor to cam and oil pump. Is this part something that is basic or more advanced? I have never needed an engine mechanic so I do not know what questions to ask to judge their knowledge and skills.
As always, I really appreciate everyone's input.
Regards,
Bob
1. Plug wires need to be repositioned 1 hole clockwise.
2. Distributor needs to be re-indexed with cam and oil pump
3. Engine needs to be retimed.
Someone asked what my degrees of advance. I do not know but the mark on the dampener is well beyond the farthest mark on the indicator, at least twice the distance between the 0 and the most advance mark.
So what affect(s) does being this far out of time have on the engine? Once everything is to spec, will this have any affect on either performance and/or fuel mileage? The engine is a stock 327/300HP with powerglide. I usually only put enough gas in for the day's drive but estimate I get 10/12 MPG.
I am not sure I am up to making the adjustments of the distributor to cam and oil pump. Is this part something that is basic or more advanced? I have never needed an engine mechanic so I do not know what questions to ask to judge their knowledge and skills.
As always, I really appreciate everyone's input.
Regards,
Bob
Thread Starter
Racer
Joined: Jun 2007
Posts: 272
Likes: 1
Update: I checked the plug wire placement and they appear to be as adivised previously in this posting. Looking down at the point adjustment window, no. 1 wire is just to the left side of the window. No. 2 is above the window and to the right side.
Drifting
Joined: Aug 2008
Posts: 1,921
Likes: 53
From: Philadelphia Pa
Now that you have the cap wired correctly, take cap off of dist. Undo dist lock down bolt, lift dist and rotate rotor clock wise one tooth, reinstall dist (make sure oil pump rod is properly located), retime.
Also, take a look a John Z's pic in post number 6 and your pic. Notice how your pic shows the number one cap post pointing slightly to the front while in John's pic it's more toward the passenger side fender. Looks like you are off by one tooth. And believe me, there's only ONE way that the distributor will fit in that area. Everything MUST be set correctly for it to work.
Also, take a look a John Z's pic in post number 6 and your pic. Notice how your pic shows the number one cap post pointing slightly to the front while in John's pic it's more toward the passenger side fender. Looks like you are off by one tooth. And believe me, there's only ONE way that the distributor will fit in that area. Everything MUST be set correctly for it to work.
Last edited by Steve59; Apr 6, 2012 at 08:49 AM.
Race Director
Joined: Nov 2000
Posts: 10,338
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From: Beverly Hills (Pine Ridge) Florida
A. Your cap is wired correctly.
B. Turning the dist. CW (away from the intake manifold runner that it is contacting) will lessen the advance.
C. Disconnect and block the vacumm line going to the vac. advance canister before adjusting the ignition timing (you may need to open the throttle a tad to keep the enging running - use a thin piece of cardboard at the throttle stop screw).
D. Note the current ignition timing (as ref.). Then reset the ignition timing per spec., and relock down the dist., and test drive.
If your timing still cannot be set correctly, then we can talk about resetting the distributor, or changing the gear position.
Plasticman
B. Turning the dist. CW (away from the intake manifold runner that it is contacting) will lessen the advance.
C. Disconnect and block the vacumm line going to the vac. advance canister before adjusting the ignition timing (you may need to open the throttle a tad to keep the enging running - use a thin piece of cardboard at the throttle stop screw).
D. Note the current ignition timing (as ref.). Then reset the ignition timing per spec., and relock down the dist., and test drive.
If your timing still cannot be set correctly, then we can talk about resetting the distributor, or changing the gear position.
Plasticman
Last edited by Plasticman; Apr 6, 2012 at 08:50 AM.
Thread Starter
Racer
Joined: Jun 2007
Posts: 272
Likes: 1
Steve69: You and others have mentioned making sure the 'oil pump pump rod is properly located' How do I know if it is properly located? I understand how the distributor gear needs to mesh with the cam gear, but I do not understand the issue with the oil pump. Do you or someone have a picture or tell me where I can see one to better idea of what I am doing?
Thanks again
Thanks again
Tech Contributor
Joined: Aug 1999
Posts: 14,365
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From: At my Bar drinking and wrenching in Lafayette Colorado
Just drop me an e-mail request for my "how to install your distributor" tech paper: JohnZ's photo is from that paper. Your distributor is installed one tooth off, and that's affecting your clocking and ability to get it timed without hitting the manifold runner - common problem. The paper will guide you through the process.
Lars
V8FastCars@msn.com
Lars
V8FastCars@msn.com