Ported vs Manifold Vacuum?
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,736
Likes: 37
From: Stockton Ca
Ported vs Manifold Vacuum?
For some strange reason my 74 idle goes too low when I come to a stop.
It comes back up slowly.
I'm thinking the vac adv is not working properly?
Or someone switched the vac hoses.
Which hose is full man vac?
TIA
R
It comes back up slowly.
I'm thinking the vac adv is not working properly?
Or someone switched the vac hoses.
Which hose is full man vac?
TIA
R
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,736
Likes: 37
From: Stockton Ca
I can pull hoses and get the timing light.
My motor has always been on full man vac.
19* adv and 32* total.
For some reason it is rough on idle.
I'm wondering is my vac adv is not working properly?
My motor has always been on full man vac.
19* adv and 32* total.
For some reason it is rough on idle.
I'm wondering is my vac adv is not working properly?
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,736
Likes: 37
From: Stockton Ca
On my AG the ports are almost side by side?
I'm being lazy, my back is killing me and I don't feel like hanging over the engine!
I'm pretty sure it already right and its a vac issue.
I don't want to deal with that!
This is what happens when a car is left in the driveway for a few years. WTF
I'm being lazy, my back is killing me and I don't feel like hanging over the engine!
I'm pretty sure it already right and its a vac issue.
I don't want to deal with that!
This is what happens when a car is left in the driveway for a few years. WTF
Race Director
Joined: Mar 2017
Posts: 11,927
Likes: 4,497
From: Virginia
Good thing it's a 74! Otherwise the CARB police would already be on the way.
If you don't have a Mity-Vac (with a gauge), or a vacuum gauge, you can test the ports with your finger.
It will take a minute of leaning over your engine, though. A Mity-Vac plus a timing light will tell you if the problem is the vac can itself, which do fail.
If you don't have a Mity-Vac (with a gauge), or a vacuum gauge, you can test the ports with your finger.
It will take a minute of leaning over your engine, though. A Mity-Vac plus a timing light will tell you if the problem is the vac can itself, which do fail.
1967 Pedal Car Champion
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Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,736
Likes: 37
From: Stockton Ca
Edl Air Gap.
I think this will get settled w/vac gauge.
There could be a small vac leak somewhere else?
I just know it didn't have this much trouble returning to a proper idle.
Some sea foam and carb cleaner are tomorrow.
It has been a while, I remember the problem solving! lol
I think this will get settled w/vac gauge.
There could be a small vac leak somewhere else?
I just know it didn't have this much trouble returning to a proper idle.
Some sea foam and carb cleaner are tomorrow.
It has been a while, I remember the problem solving! lol
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Who says its vacuum related?
Could be the fast idle choke decides to cancel late, once and for all.
Could be the rusty springs / weights in the dizzy.
Could be some weird chit going on with the secondary throttle shaft.
Could be the fast idle choke decides to cancel late, once and for all.
Could be the rusty springs / weights in the dizzy.
Could be some weird chit going on with the secondary throttle shaft.
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From: Sunshine Coast, Queensland, Australia
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Cruise-In VIII Veteran
Imagine, being a professional mechanic, with only 50 years of practice. Just learning obviously.
One of the things We Joke about the MOST at work.
is YouTube video's!
People who know how to make video's make video's.
People who know how to repair vehicles have no F in clue how to make video's and don't give 2 *****!
WATCH all the you tube videos you can. The guys that actually know how to repair your car are laughing.
One of the things We Joke about the MOST at work.
is YouTube video's!
People who know how to make video's make video's.
People who know how to repair vehicles have no F in clue how to make video's and don't give 2 *****!
WATCH all the you tube videos you can. The guys that actually know how to repair your car are laughing.
Melting Slicks
Joined: May 2021
Posts: 2,264
Likes: 1,309
From: Fleming Island, FL
Imagine, being a professional mechanic, with only 50 years of practice. Just learning obviously.
One of the things We Joke about the MOST at work.
is YouTube video's!
People who know how to make video's make video's.
People who know how to repair vehicles have no F in clue how to make video's and don't give 2 *****!
WATCH all the you tube videos you can. The guys that actually know how to repair your car are laughing.
One of the things We Joke about the MOST at work.
is YouTube video's!
People who know how to make video's make video's.
People who know how to repair vehicles have no F in clue how to make video's and don't give 2 *****!
WATCH all the you tube videos you can. The guys that actually know how to repair your car are laughing.
There are a few good Youtube channels. Jammie of "Dead Dodge Garage" makes excellent videos and knows his stuff too.
Race Director
Joined: May 2006
Posts: 18,695
Likes: 2,572
On my AG the ports are almost side by side?
I'm being lazy, my back is killing me and I don't feel like hanging over the engine!
I'm pretty sure it already right and its a vac issue.
I don't want to deal with that!
This is what happens when a car is left in the driveway for a few years. WTF
I'm being lazy, my back is killing me and I don't feel like hanging over the engine!
I'm pretty sure it already right and its a vac issue.
I don't want to deal with that!
This is what happens when a car is left in the driveway for a few years. WTF
A timing light will tell you if your vacuum advance is working.