When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
As for the PCV system, You should have fresh air going in so that its easier for the vapors that are in there to get sucked out. You dont need a hose going to the air cleaner, you can just use a plug in little valve cover breather in the oil fill hole. https://www.summitracing.com/parts/k...1490/overview/
Okay! So just to be clear, all I need to do is take out the cap circled in the picture and replace it with that filter? No alterations to the drivers' side valve covers/hoses? Also. Sidenote. I have never poured oil into the passenger side cap. Should I be? I thought it all poured in through the drivers' side oil cap on the valve, as that's where the dipstick is. But now I'm wondering why that cap is there if not to also pour oil into.
Here's a PCV diagram that is so old (in Internet years), that it is a static GIF!
The breather hose on the passenger side lets in filtered air from the air cleaner (and, consequently, prevents oil vapor mist from covering your engine compartment). The PCV lets the manifold vacuum suck out the blowby vapors, and that's the important part, but there must be a breather on the other valve cover, too, whether pulling from the air cleaner through a filter (stock in later years), or just from the engine compartment (as many aftermarket systems, do).
Have you considered a drop-base air cleaner? If you can find one that fits, it might give you more filter area for the same hood clearance.
You may also want to pickup a mechanic's stethoscope to diagnose the location of engine noises. A vacuum hose will work in a pinch.
Thanks so much! This helped me make sense of it all. What my current system is missing is a point of entry for clean air to enter the valves. If I add the filter on the passenger side oil cap, clear air will enter down into the valves, flow through the engine, come out through the hose (on my drivers side oil filler cap), and enter into carb to be recycled. Correct?
Even 2 inches is going to be too high. But I agree I need to put the bigger cleaner back on. I will have to cut a paper filter in half and screw it down tight. That's what I have done with the current air filter there. It's cut down to probably less than an inch tall.
Here's my buddy's 1970 350 engine setup which is just like your's. The carb is an Edelbrock 1406 with an Edelbrock 1221 Air Filter with a 2" element. I put some bits of clay on top of the filter and then closed the hood. As you can see, the hood didn't even touch the 1/2" high bits of clay.
2" filter element inside an Edelbrock #1221 assembly sitting on top of an Edelbrock 1406 Carb. Lots of clearance!
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Originally Posted by BlankSlate
Thanks so much! This helped me make sense of it all. What my current system is missing is a point of entry for clean air to enter the valves. If I add the filter on the passenger side oil cap, clear air will enter down into the valves, flow through the engine, come out through the hose (on my drivers side oil filler cap), and enter into carb to be recycled. Correct?
Alright! Went down to Pep Boys and grabbed a breather. But as with everything on this car, nothing is easy. As you can see, the air pressure cannister that raises the wiper shield is blocking the way. Can't fit.
Seems like the simplest fix would be to swap the oil filler cap with the hose running to the carb (on the drivers side valve cover) to the passenger side valve cover. Is that okay to do? I figured it was but wanted to double check. As you can see, the breather would have plenty of room on the drivers side. And the hose-connected cap should fit on the passenger side.
The PCV has an intended orientation based on the engine rotation. In theory, the as the crank rotates, air is pulled from the passenger side and blow towards the drivers side. In practice, it may not matter much, so your idea is likely better than what you have.
I'd try to find some correct valve covers which will be shorter, and may provide the room you need, provided you don't have roller rockers installed.
Rough night. Stayed up til 5 AM (still awake) working on it. Got the throttle replaced, but it was a nightmare putting the linkage for the gas pedal back in. But that would all be fine if it weren't for what happened when I tried to start the car.
The engine screamed. SCREAMED. When I hit the accelerator. Smelled a little smoke after. I am scared to death I somehow messed something vital up while tinkering with the throttle, but idk how. Maybe I damaged some wiring while under the dash. Or maybe my new setup is causing the scream (again, its not a squeal. A SCREAM.) Take a look at my new setup and see if you can spot any potential causes of the noise.
I am a little relieved because I googled engine screaming, and it sounds like it could just be alternator belt. But why on earth was that affected while I worked on my carb?
Other details: I HAD been hearing a sortve high pitched buzz when I drove earlier in the week. Maybe that was the belt in the early stages of going bad?
I also took out the AC plastic from behind my dash. My AC isnt equipped, so it was just in the way. Again, idk how that would cause the noise but just giving all the information.
Please help!
Originally Posted by Rescue Rogers
As for the PCV system, You should have fresh air going in so that its easier for the vapors that are in there to get sucked out. You dont need a hose going to the air cleaner, you can just use a plug in little valve cover breather in the oil fill hole. https://www.summitracing.com/parts/k...1490/overview/
Originally Posted by Bikespace
Here's a PCV diagram that is so old (in Internet years), that it is a static GIF!
The breather hose on the passenger side lets in filtered air from the air cleaner (and, consequently, prevents oil vapor mist from covering your engine compartment). The PCV lets the manifold vacuum suck out the blowby vapors, and that's the important part, but there must be a breather on the other valve cover, too, whether pulling from the air cleaner through a filter (stock in later years), or just from the engine compartment (as many aftermarket systems, do).
Have you considered a drop-base air cleaner? If you can find one that fits, it might give you more filter area for the same hood clearance.
You may also want to pickup a mechanic's stethoscope to diagnose the location of engine noises. A vacuum hose will work in a pinch.
Regards the PCV valve and orientation....take a look at the pic you posted of your engine and then the reference from the Zip Corvettes description of standard valve covers and how they are oriented on the engine regards passenger side and driver's side.
The covers are on the wrong sides.
Bubba has been all over your car.
Some engines on other cars run the PCV hose out of the carb base over to a valve cover and the PVC valve is inline that hose. As opposed to the PCV being mounted into the grommet in the valve cover. Looks like that is what you have here (minus the PCV valve). Typically the grommet for a PCV valve into the valve cover is a smaller hole.
Larger grommets/holes are often old style breathers pre-PVC days.
You could fix your setup but it might be easier to just look at what was stock and using that.
Someone tried to make shiny chrome valve covers work, without looking at how the system is designed to work..
Btw.....taping the gas line to a HOT water heater line is not a good idea. You are heating up the fuel right at that spot.
No insult intended but that is a bubba move.
Keep working at it.
You'll learn.
Experience is often the best teacher. It just takes time and proper research.
Last edited by bmans vette; 05-22-2019 at 05:21 PM.
Did your model year come with a fuel tank vapor canister?
If it did, the PVC on the driver's side is supposed to have a T fitting that hooks up one side to the fuel vapor canister.
It could be the previous owner just got rid of it, but it is supposed to help with the gas smell.
The engine should run fine without it, but could be a good functional project in the future.
There are many types of breathers, you may just shop around for 1 with a lower profile.
That edelbrock carb seems to be causing all kinds of bubba with your engine; for safety and performance sake, I think it's worth finding a used quadrajet and rebuilding it. Maybe someone on craigslist would even trade for your Edelbrock carb. I know it's summer time and you probably just want to drive the thing, but I would think about this at least in the long term.
In a prior post you mentioned the engine made sounds like rushing air when pressing on the gas pedal. It's tough to tell with a video, but this could just be the clutch fan on the front of the water pump pushing more air, but it could also could be a vacuum line that's uncapped. Could be smart to plug all the vacuum lines other than for distributor to test it.
Last edited by mongoose87; 05-22-2019 at 06:58 PM.
Regards the PCV valve and orientation....take a look at the pic you posted of your engine and then the reference from the Zip Corvettes description of standard valve covers and how they are oriented on the engine regards passenger side and driver's side.
The covers are on the wrong sides.
Bubba has been all over your car.
Some engines on other cars run the PCV hose out of the carb base over to a valve cover and the PVC valve is inline that hose. As opposed to the PCV being mounted into the grommet in the valve cover. Looks like that is what you have here (minus the PCV valve). Typically the grommet for a PCV valve into the valve cover is a smaller hole.
Larger grommets/holes are often old style breathers pre-PVC days.
You could fix your setup but it might be easier to just look at what was stock and using that.
Someone tried to make shiny chrome valve covers work, without looking at how the system is designed to work..
Btw.....taping the gas line to a HOT water heater line is not a good idea. You are heating up the fuel right at that spot.
No insult intended but that is a bubba move.
Keep working at it.
You'll learn.
Experience is often the best teacher. It just takes time and proper research.
Thanks! Are you certain about the wrong side thing? Most 69 corvette engines I find have the breather on the back passenger side, just like mine. As well as the hose on the drivers' side, just like mine.
And just to clarify, I didn't tape the fuel line to the hose. I WRAPPED the fuel line and the hose (separately) with heat reductive tape.
Last edited by BlankSlate; 05-22-2019 at 07:32 PM.
Thanks! Are you certain about the wrong side thing? Most 69 corvette engines I find have the breather on the back passenger side, just like mine. As well as the hose on the drivers' side, just like mine.
And just to clarify, I didn't tape the fuel line to the hose. I WRAPPED the fuel line and the hose (separately) with heat reductive tape.
That's the way mine came, stock as pictured. But mine has the shorter pancake style late '69 wiper canister.....which would allow more room for a breather.
Thanks! Are you certain about the wrong side thing? Most 69 corvette engines I find have the breather on the back passenger side, just like mine. As well as the hose on the drivers' side, just like mine.
And just to clarify, I didn't tape the fuel line to the hose. I WRAPPED the fuel line and the hose (separately) with heat reductive tape.
AND your pic shows that there is a fill cap in the place where the breather is supposed to be on the engine (passenger rear hole).
So how is yours the same for every other 69 out there? I must be missing something.
And if you think the fuel line, heat resistant taped to the heater line is fine....ok...... your car.
Later
05-20-2019, 07:03 PM
