CRG Discussion Forum

Camaro Research Group Discussion => Maintenance => Topic started by: 69z28302 on November 26, 2011, 07:43:13 PM

Title: 69 Dist, Vacuum advance
Post by: 69z28302 on November 26, 2011, 07:43:13 PM

Hey Camaro enthusiast. I'm having trouble with the vacuum advance when I connect it. The car runs fine disconnected and plugged. Set the timing and connect it it shoots the idle way up . The I adjust the idle down and and bleep the throttle and it very slow to return to idle. Both the Distributor and the carb have been rebuilt by very reputable people (but not the same) .

Any Idea's


Thanks CRG
MIke

Title: Re: 69 Dist, Vacuum advance
Post by: Boston14 on November 26, 2011, 09:41:36 PM

Did you read John Z's technical article on ignition timing? Very informative.   :)   http://www.camaros.org/pdf/timing101.pdf

boston14

Title: Re: 69 Dist, Vacuum advance
Post by: TODD on November 26, 2011, 11:11:27 PM

Mike;
My 302 did not like the vacuum can advertised 15 degrees at 8 in hg.
Here's my setup, 15 degrees at crank / 10 degrees distributor (20 crank) total 35 degrees mechanical.
Test driving with vacuum my car would only stand 9 degrees at high speed cruise and idle decently.
I accomplished the vac setting by making my own vac canister stop.
My car would did exhibit a good idle at 30 (15 advance + 15 vac can) it does ok with 24 degrees and no ping at high speed cruise.
Todd

Title: Re: 69 Dist, Vacuum advance
Post by: 69z28302 on November 26, 2011, 11:42:36 PM

My buddy has my timing light with the adavance. When I get I'll set it at the recommended 36 TOTAL  that the restorer recommends and see what happens. I'm wondering if the breaker plate could be binding some how?

I read the John Z article. It was very helpful and well written. 

thanks

Mike

Title: Re: 69 Dist, Vacuum advance
Post by: JohnZ on November 27, 2011, 06:05:45 PM

Quote from: 69z28302 on November 26, 2011, 07:43:13 PM

The I adjust the idle down and and bleep the throttle and it very slow to return to idle. Any Idea's


Thanks CRG
MIke

Sounds like the breaker plate pivot is binding on the upper bushing; it should move freely, and the thick felt washer under it should be saturated with oil - that's the only lubrication the breaker plate pivot gets.

Title: Re: 69 Dist, Vacuum advance
Post by: 69z28302 on November 27, 2011, 06:16:35 PM

I thought that too John. What's the fix? Take it apart and check that plate for binding?

Thx
MIke

Title: Re: 69 Dist, Vacuum advance
Post by: firstgenaddict on November 28, 2011, 05:05:32 PM

Pull the distributor cap off, use a vacuum pump brake bleeder etc, hook it to the vac can and apply vacuum, If is doesn't move there is a problem which must be further investigated.
Next step would be to remove the vac can and see if the plate will rotate by hand.
If you take the VAC can off the distributor the plate should rotate freely.


BTW if you don't have a vac bleeder etc I have pulled another car up beside and used a long piece of hose.