Engine problem? Question PLEASE HELP!
Thread Starter
Drifting
Joined: Aug 2000
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From: Peoria AZ
Engine problem? Question PLEASE HELP!
Ok...The engine I currently have in my 65 is a 383 stroker motor, it was installed by the previous owner. It is a 350 block with steel stroker crank, eagle rods, roller cam, twisted wedge heads etc. BUT he wanted it to appear correct so it has the original 461 intake, original carb and the original valve covers on it. I am dangerous enough to know all of the basics on an engine and I have changed many an engine but I still just know just enough to hurt myself..lol. An engine needs to be vented in some way correct? When this guy installed this engine he had a hole drilled into the back of the block that has a 90 degree elbow on it and it wasn't hooked up to anything when I bought the car but it blew oil all over my engine compartment..I talked to a guy here in town and he said just hook it to the carb...I did that and no more oil over my engine compartment BUT when I shut the engine off it always makes a WHOOSH sound that only lasts like 1 second like its letting air out of somewhere. I am assuming something isn't correct. Any help would be much appreciated! 
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From: Washington Michigan
With that setup, the carb is drawing vacuum from the hole in the back of the block (with no method of metering the flow), but there's no "intake" to get fresh air INTO the crankcase.
A better setup would be to connect a hose from the existing elbow at the back of the block to the elbow in the base of the air cleaner (the "intake" side of the system), and use another hose from the nipple on the oil fill tube to the special 90* fitting (with an .090" orifice in it) that screws into the hole in the center of the carb main body on the driver's side (the "exhaust" side of the system). That will give you exactly the same setup in terms of PCV flow as the original '65 arrangement.
A better setup would be to connect a hose from the existing elbow at the back of the block to the elbow in the base of the air cleaner (the "intake" side of the system), and use another hose from the nipple on the oil fill tube to the special 90* fitting (with an .090" orifice in it) that screws into the hole in the center of the carb main body on the driver's side (the "exhaust" side of the system). That will give you exactly the same setup in terms of PCV flow as the original '65 arrangement.
Thread Starter
Drifting
Joined: Aug 2000
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From: Peoria AZ
OK...just to verify what I think you are saying....run a hose from the elbow that was added in the back of the block to the nipple on the bottom of my air cleaner...and then run a hose from the oilfill to the nipple on the base of the carb. Is that correct?
I also just went outside to make sure I had the nipple on the air cleaner and I do....but...I don't have it hooked up as I said I did. I remember now that the guy that was helping me (over the phone) told me I didn't need the hole in the back of the block (I think I do and I think you are saying I do) so he had me cap it off. So what I have right now is that extra hole with the 90* is capped off and I have a hose running from the oilfill tube to the carb base. So I think what you are saying is I just need to run a hose from the extra 90* in the back of the block to the nipple on my air cleaner...is that correct? Thanks for your help!!
I also just went outside to make sure I had the nipple on the air cleaner and I do....but...I don't have it hooked up as I said I did. I remember now that the guy that was helping me (over the phone) told me I didn't need the hole in the back of the block (I think I do and I think you are saying I do) so he had me cap it off. So what I have right now is that extra hole with the 90* is capped off and I have a hose running from the oilfill tube to the carb base. So I think what you are saying is I just need to run a hose from the extra 90* in the back of the block to the nipple on my air cleaner...is that correct? Thanks for your help!!
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From: Dove Mountain Arizona
You need a modified pcv system, not a closed system. Air from one valve cover thru a pcv valve to the base of the carb (vacuum) AND a passive air inlet (oil filler on other valve cover or the old style filler neck on the intake). Without it you run the possibility of blowing out your intake gaskets. Pic
Last edited by MasterDave; Jan 18, 2008 at 01:37 PM.
Thread Starter
Drifting
Joined: Aug 2000
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From: Peoria AZ
I would REALLY like to avoid changing the valve covers as it looks TOTALLY stock right now and if at all possible I would like to keep it that way. If there is no other way then I guess I would have to but it sounds like JohnZ thinks it will work without, if I am reading his post correctly.
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From: Camp Verde AZ
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Do a search on some posts started by me last December and you will see pics of my block that show a hole drilled in the back. That hole is connected to a line that has a PCV valve in it, and connects to the base of the carb. I have another intake vent in the manifold that allows outside air into the block, you simply connect an oil filler tube vent to the base of your air cleaner, or run it the other way, , doesn' matter.
Make sure you put the PCV valve in the right direction.
Doug
Make sure you put the PCV valve in the right direction.
Doug
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Brett Foote
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From: Greenville, Indiana
[QUOTE=Sean Dunshee;1563684611]OK...just to verify what I think you are saying....run a hose from the elbow that was added in the back of the block to the nipple on the bottom of my air cleaner...and then run a hose from the oilfill to the nipple on the base of the carb. Is that correct?
That's correct. On the vacuum source at the carb, make sure you use a metered orfice like the '65 engines have or use a compatible PCV valve. The air cleaner end should be inside of the air cleaner element to avoid oil vapor contamination.
This will give you a vacuum source to pull in clean filtered air thorugh the air cleaner hose and into the block and then circulate back to the vacuum source.
If you start getting some blowby, it may force oil vapor condesation up in your air cleaner from time/time due to the lack of an oil separator in the block behind the 90* fitting.
That's correct. On the vacuum source at the carb, make sure you use a metered orfice like the '65 engines have or use a compatible PCV valve. The air cleaner end should be inside of the air cleaner element to avoid oil vapor contamination.
This will give you a vacuum source to pull in clean filtered air thorugh the air cleaner hose and into the block and then circulate back to the vacuum source.
If you start getting some blowby, it may force oil vapor condesation up in your air cleaner from time/time due to the lack of an oil separator in the block behind the 90* fitting.
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From: Greenville, Indiana
The metered orfice Chevrolet used screw into the carb base and had a very small hole in it. I don't remember the orfice size but it's maybe a little bigger than paper clip diameter. The nipple size is for 3/8's" hose I believe.
You Holley probably has a very large opening in it which would be okay for a PCV valve but way too big to just slip the hose over it. There may be a vacuum opening on the Holley to screw in the orfice. I don't know.
You can get an oil fill pipe for a '65 engine that has provisions to screw a PCV valve right into it. Then, just run the hose from the valve to the big nipple on the carb and leave your other hose going from the air cleaner to the back of the block.
You Holley probably has a very large opening in it which would be okay for a PCV valve but way too big to just slip the hose over it. There may be a vacuum opening on the Holley to screw in the orfice. I don't know.
You can get an oil fill pipe for a '65 engine that has provisions to screw a PCV valve right into it. Then, just run the hose from the valve to the big nipple on the carb and leave your other hose going from the air cleaner to the back of the block.
Thread Starter
Drifting
Joined: Aug 2000
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From: Peoria AZ
OK..I see what you guys are talking about. I totally was missing what was in JohnZs picture. I see the 90* elbow with the orifice you guys are talking about..Im a little slow..lol. Ok..my current carb does NOT have that elbow nor a provision for it. But, I have my matching numbers engine all restored sitting in a bag and I have a restored dated carb on it that does have what I am looking for, I was planning on just usuning that carb whenever I decided to swap my engine back to NCRS but I think I will instead put it on tomorrow and route everything as you guys are saying. Now, one last question, on the 327 engines I am assuming that the large tube from the back of the block to the large tube on the air cleaner is the same thing that I am trying to replicate on my 350 block..is that correct? And if so...will the 3/8" hose that I have going to my extra hole and elbow going to be large enough to acomplish what I need?
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From: Camp Verde AZ
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Take a drive down to Tempe this Sunday Or saturday early afternoon, (like around noon) and I will show you everything you need to know/do to geta PCV valve installed. I can set you up with a real professional install.
Call me at 480-967-6218 for directions. IM me if you are going to come down.
Doug
Call me at 480-967-6218 for directions. IM me if you are going to come down.
Doug
Thread Starter
Drifting
Joined: Aug 2000
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From: Peoria AZ
That is an awesome offer I will have to take you up on...more so that I want to see that 427ci 61..lol...Is it something that I have to bring my corvette for? To be honest I have never driven my Vette that far and I kinda hate to because I don't know how much I trust it.
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From: Camp Verde AZ
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You don't need the car here, but if I can actually see what you have, i can send you to the hardware and auto parts store and make a PCV adaptor while you wait (requires a lathe). Other wise, you can look at mine to see what i did and do it at your leisure.
Doug
Doug
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From: Camp Verde AZ
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480-967-6218
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From: Washington Michigan
OK..I see what you guys are talking about. I totally was missing what was in JohnZs picture. I see the 90* elbow with the orifice you guys are talking about..Im a little slow..lol. Ok..my current carb does NOT have that elbow nor a provision for it. But, I have my matching numbers engine all restored sitting in a bag and I have a restored dated carb on it that does have what I am looking for, I was planning on just usuning that carb whenever I decided to swap my engine back to NCRS but I think I will instead put it on tomorrow and route everything as you guys are saying.
If you use the original carb, use the '65 oil fill tube (has a nipple on it) with the hose to the special fitting on the side of the carb (Paragon has that 90* fitting with the .090" orifice in it).