Another PCV valve question, cycle rate?
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Joined: Jul 2008
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From: Airdrie Alberta
Another PCV valve question, cycle rate?
To get my 79 on the road, one of the things I did was put in a new PCV valve. When it's idling, the PCV valve sounds like its opening/closing super fast,, and when I take it out and plug the bottom, the motor idle smooths out,,, is this normal to have the PCV valve cycling so fast?
I know my distributor was bubba'd,, it needs to be reset one tooth and the vacuum tubing has been bubba'd to fix the removal of most of the polution control,,, so assuming the vacuum is hooked up correctly,, is the pcv cycling normal?, or should be "open" all the time at idle?
Thanks guys
David.
I know my distributor was bubba'd,, it needs to be reset one tooth and the vacuum tubing has been bubba'd to fix the removal of most of the polution control,,, so assuming the vacuum is hooked up correctly,, is the pcv cycling normal?, or should be "open" all the time at idle?
Thanks guys
David.
Drifting
Joined: Apr 2008
Posts: 1,305
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From: Lewisburg WV
thegazman
Are you sure your PCV is hooked up to the right port on the carb? Do you have the stock Q-Jet carb? I assume your car is a 79. I have a 79 L82, but I'm sure the line routing would be the same. Let me know. I can take a picture of mine and forward it to you. All of my smog equipment has been removed.
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Joined: Jul 2008
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From: Airdrie Alberta
thegazman,, if you could send me your routing picture, that would give me an excellent start.
As far as I know,,, I have the original L48 motor and carb. I haven't done any number matching research yet, with as far as I know 28K miles,, I haven't yet felt the need.
Many thanks!
David.
As far as I know,,, I have the original L48 motor and carb. I haven't done any number matching research yet, with as far as I know 28K miles,, I haven't yet felt the need.
Many thanks!
David.
Are you sure your PCV is hooked up to the right port on the carb? Do you have the stock Q-Jet carb? I assume your car is a 79. I have a 79 L82, but I'm sure the line routing would be the same. Let me know. I can take a picture of mine and forward it to you. All of my smog equipment has been removed.
Drifting
Joined: Apr 2008
Posts: 1,305
Likes: 2
From: Lewisburg WV
thegazman
David....Here's a photo of my PVC and vacuum advance routing. As you may notice I have modified most of smog equipment; however, the PVC and vacuum advance lines are still attached in the same place on the Q-Jet carb as the original.
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Joined: Jul 2008
Posts: 60
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From: Airdrie Alberta
thegazman & pws69,,, many thanks,,, now I have something to play with tonight.
Once I get the PCV/vacuum/advance lines straightened out, I can find #1 TDC and reset the distributor and do a little timing.
Thanks again!
David.
Once I get the PCV/vacuum/advance lines straightened out, I can find #1 TDC and reset the distributor and do a little timing.
Thanks again!
David.
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Joined: Jul 2008
Posts: 60
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From: Airdrie Alberta
I found the distributor at least one cog off,, it's sitting in correct now and it takes just a quick flip off the key to fire instead of a 10 second crank. I used a vacuum gauge to prelim set the timing and this weekend buddy is bringing his timing light. The PCV valve tubing does come off the correct port, but a vacuum line splits off it and runs to the fender fume cannister. The PCV valve still cycles like a sewing machine(?) I checked the PCV vent line and there is definitely suction there when the PCV valve is in so it is working,, maybe a different valve will stop the cyclic clatter,, any suggestions?,, and instead of 220 degrees at idle, the gauge never went over 200(195 thermostat) the whole time it was idling.
One thing I'm still struggling with is the dual snorkel flap vaccuum,,, the flaps with no vacuum stay open, and with vacuum they close. Just the way it should be,,, because Bubba got into the vacuum lines sometime(s) over the last 30 years, and he disconnected the lines,,, could someone help me with getting the snorkel flap tubing back to the way it should be so they work properly?
Edit after: Is this the answer? http://forums.corvetteforum.com/show...snorkel+vacuum
Thanks for all the help so far,, this is a great forum with great people.
David.
One thing I'm still struggling with is the dual snorkel flap vaccuum,,, the flaps with no vacuum stay open, and with vacuum they close. Just the way it should be,,, because Bubba got into the vacuum lines sometime(s) over the last 30 years, and he disconnected the lines,,, could someone help me with getting the snorkel flap tubing back to the way it should be so they work properly?
Edit after: Is this the answer? http://forums.corvetteforum.com/show...snorkel+vacuum
Thanks for all the help so far,, this is a great forum with great people.
David.
Last edited by dewm1; Aug 29, 2008 at 09:21 AM. Reason: speeling!
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
I found the distributor at least one cog off,, it's sitting in correct now and it takes just a quick flip off the key to fire instead of a 10 second crank. I used a vacuum gauge to prelim set the timing and this weekend buddy is bringing his timing light. The PCV valve tubing does come off the correct port, but a vacuum line splits off it and runs to the fender fume cannister. The PCV valve still cycles like a sewing machine(?) I checked the PCV vent line and there is definitely suction there when the PCV valve is in so it is working,, maybe a different valve will stop the cyclic clatter,, any suggestions?,, and instead of 220 degrees at idle, the gauge never went over 200(195 thermostat) the whole time it was idling.
One thing I'm still struggling with is the dual snorkel flap vaccuum,,, the flaps with no vacuum stay open, and with vacuum they close. Just the way it should be,,, because Bubba got into the vacuum lines sometime(s) over the last 30 years, and he disconnected the lines,,, could someone help me with getting the snorkel flap tubing back to the way it should be so they work properly?
Edit after: Is this the answer? http://forums.corvetteforum.com/show...snorkel+vacuum
Thanks for all the help so far,, this is a great forum with great people.
David.
One thing I'm still struggling with is the dual snorkel flap vaccuum,,, the flaps with no vacuum stay open, and with vacuum they close. Just the way it should be,,, because Bubba got into the vacuum lines sometime(s) over the last 30 years, and he disconnected the lines,,, could someone help me with getting the snorkel flap tubing back to the way it should be so they work properly?
Edit after: Is this the answer? http://forums.corvetteforum.com/show...snorkel+vacuum
Thanks for all the help so far,, this is a great forum with great people.
David.
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Thread Starter
Advanced
Joined: Jul 2008
Posts: 60
Likes: 0
From: Airdrie Alberta
SH-60B and paul67,, buddy at NAPA asked if it was a L48 or a L82,, so I have to assume it's the right one,,,.
There's more tuning and rebuilding of the carb and distributor in the near future so once that's done with all the vacuum tubing replaced, then we'll see what it's up to.
Thanks!
There's more tuning and rebuilding of the carb and distributor in the near future so once that's done with all the vacuum tubing replaced, then we'll see what it's up to.
Thanks!
