72 Dart 360 PVC valve issues

[middleagecrisis]

Two thoughts for you. First, do you have the PCV line in a valve cover hole that is baffled? You could be pulling oil in if it’s an open hole with no baffle. Second, could be that your valve guides are excessively worn and your rings not so much. My duster came with a 318 that smoked oil quite a bit at idle. I simply put new valve stem seals on it, as the old ones were completely gone with just disintegrated remnants in the valve area. After doing so, no more smoke at idle and the motor runs very good for what it is. I would check the PVC valve first and then determine when the motor is smoking. If at idle, or just after startup, it’s most likely the valve stem seals. If it’s all the time, most likely, the rings are the major culprit. This will give you an idea where you’re getting your blow by. I agree the ignition timing isn’t the problem.

 

[Brandenthepilot]

Two thoughts for you. First, do you have the PCV line in a valve cover hole that is baffled? You could be pulling oil in if it’s an open hole with no baffle. Second, could be that your valve guides are excessively worn and your rings not so much. My duster came with a 318 that smoked oil quite a bit at idle. I simply put new valve stem seals on it, as the old ones were completely gone with just disintegrated remnants in the valve area. After doing so, no more smoke at idle and the motor runs very good for what it is. I would check the PVC valve first and then determine when the motor is smoking. If at idle, or just after startup, it’s most likely the valve stem seals. If it’s all the time, most likely, the rings are the major culprit. This will give you an idea where you’re getting your blow by. I agree the ignition timing isn’t the problem.

The smoking is bad at idle... but doesnt go away when actually driving the car. the only time the smoke went away is when I tookthe PVC off and just put the hose in. My initial thought was that the valve wasnt creating enough suction.

 

[middleagecrisis]

If you remove the PCV valve and shake it, can you hear the little ball moving around inside? Have you tried other vacuum sources for the PCV valve besides where you have it? Does the hole where the PCV valve is plugged into have a baffle in it or does it go straight through to the head?

 

[Brandenthepilot]

If you remove the PCV valve and shake it, can you hear the little ball moving around inside? Have you tried other vacuum sources for the PCV valve besides where you have it? Does the hole where the PCV valve is plugged into have a baffle in it or does it go straight through to the head?

I haven’t tried other vacuum sources yet. When I remember the valve it seems to have great suction at the hose, just not when the valve is in. And yes the covers have baffles

 

[Brandenthepilot]

Take the oil fill cap off while it is running and put your hand over the hole to see if there is pressure building there.

Don't want a lot of pressure there or it can start pushing oil out the rear main, and that's no fun to fix.


☆☆☆☆☆

There’s definitely pressure in the oil fill cap.

 

[Brandenthepilot]

Just an update on this.

Pulled the hose off and cleaned it as much as possible going to the manifold.

I removed the oil filler cap, and there’s significant pressure being pushed out. Let the engine warm up a bit and there’s been some smoke coming from the passenger side headers. Not sure if there oil falling on the from somewhere specific, but when I was changing the spark plugs, I noticed there was oil in the number 8 plug.

Could that be a sign of significant blow by?

 

[George Jets]

If the car had been sitting for a long time, then you need to reseat the rings.

They get carboned up and don't push out to the cylinder walls to seal like they are supposed to. 1 pint of seafoam in the oil take it out and run it, then let the car sit for a week so the sea foam can do it's job loosening up the rings.

Then fire it up, warm it up and then change out the oil and filter using 5w 30 (thin is key), then take it out and run it good to heat it up for about an hour. Then change out the oil and filter again and go back to your regular oil 10w 30 and rings should start sealing better by now and problems go away.

If you really want to attach the carbon around the rings, pull all the plugs and put 1 oz of seafoam in each cylinder and let it sit for a week. Your oil will turn paint black after doing this. Then go though the routine above changing out to the thin oil etc....

Have saved many an engine by doing this and have gotten them to burn clean by cleaning the carbon from the rings with seafoam, then they are able to expand out again and wear into the cylinder walls again to make a good seal. Diesel engine too, no more smoke out the exhaust.

Here is proof this works, this truck sat in a pasture for 6 years outside, has 96,000 miles on it. When it first started up it smoked... pretty bad. Did the seafoam down the spark plug holes and let it set, multiple oil changes back to back over a 2 week period.

Running nice and strong now and no more smoke out the tailpipe, rings are seated again. Proof's in the pudding.

Yes it's my custom built ignition.


If your PCV is rattling, back down your timing and it will take car of that too. Ask me how I know.....


* * * * *

 

[Bewy]

[1] I told you in post #22 that the engine is worn. If it is THAT worn that the you are getting oil in the spark plug,
then the only fix........is to strip the engine & fix it properly.
[2] A worn engine can carbon up the PCV such that it no longer rattles. A 'rattle' test is not conclusive for an engine like this. It has gone beyond testing PCVs....

 

[RustyRatRod]

Another side note not related to your PCV issues, but is nonetheless very important. Your throttle pressure (kickdown) linkage is adjusted very poorly. The throttle pin on the carburetor should be at the rear most of the slot in the linkage so that as soon as the throttle is opened, it begins to push the kickdown linkage back. As it is now, the transmission is not getting proper line pressure when it should be. That will eventually end the life of your transmission if it's not already damaged it.

 

[Brandenthepilot]

If the car had been sitting for a long time, then you need to reseat the rings.

They get carboned up and don't push out to the cylinder walls to seal like they are supposed to. 1 pint of seafoam in the oil take it out and run it, then let the car sit for a week so the sea foam can do it's job loosening up the rings.

Then fire it up, warm it up and then change out the oil and filter using 5w 30 (thin is key), then take it out and run it good to heat it up for about an hour. Then change out the oil and filter again and go back to your regular oil 10w 30 and rings should start sealing better by now and problems go away.

If you really want to attach the carbon around the rings, pull all the plugs and put 1 oz of seafoam in each cylinder and let it sit for a week. Your oil will turn paint black after doing this. Then go though the routine above changing out to the thin oil etc....

Have saved many an engine by doing this and have gotten them to burn clean by cleaning the carbon from the rings with seafoam, then they are able to expand out again and wear into the cylinder walls again to make a good seal. Diesel engine too, no more smoke out the exhaust.

Here is proof this works, this truck sat in a pasture for 6 years outside, has 96,000 miles on it. When it first started up it smoked... pretty bad. Did the seafoam down the spark plug holes and let it set, multiple oil changes back to back over a 2 week period.

Running nice and strong now and no more smoke out the tailpipe, rings are seated again. Proof's in the pudding.


View attachment 1716384572

View attachment 1716384573

Yes it's my custom built ignition.


If your PCV is rattling, back down your timing and it will take car of that too. Ask me how I know.....


* * * * *

I’m going to give this a shock. This weekend and see what happens. Going to post the c

If the car had been sitting for a long time, then you need to reseat the rings.

They get carboned up and don't push out to the cylinder walls to seal like they are supposed to. 1 pint of seafoam in the oil take it out and run it, then let the car sit for a week so the sea foam can do it's job loosening up the rings.

Then fire it up, warm it up and then change out the oil and filter using 5w 30 (thin is key), then take it out and run it good to heat it up for about an hour. Then change out the oil and filter again and go back to your regular oil 10w 30 and rings should start sealing better by now and problems go away.

If you really want to attach the carbon around the rings, pull all the plugs and put 1 oz of seafoam in each cylinder and let it sit for a week. Your oil will turn paint black after doing this. Then go though the routine above changing out to the thin oil etc....

Have saved many an engine by doing this and have gotten them to burn clean by cleaning the carbon from the rings with seafoam, then they are able to expand out again and wear into the cylinder walls again to make a good seal. Diesel engine too, no more smoke out the exhaust.

Here is proof this works, this truck sat in a pasture for 6 years outside, has 96,000 miles on it. When it first started up it smoked... pretty bad. Did the seafoam down the spark plug holes and let it set, multiple oil changes back to back over a 2 week period.

Running nice and strong now and no more smoke out the tailpipe, rings are seated again. Proof's in the pudding.


View attachment 1716384572

View attachment 1716384573

Yes it's my custom built ignition.


If your PCV is rattling, back down your timing and it will take car of that too. Ask me how I know.....


* * * * *

Doing a compression test today just to do it. I’ll get all of this done this weekend and see what happens, I appreciate the help. I’ll keep you posted.

 

[Brandenthepilot]

[1] I told you in post #22 that the engine is worn. If it is THAT worn that the you are getting oil in the spark plug,
then the only fix........is to strip the engine & fix it properly.
[2] A worn engine can carbon up the PCV such that it no longer rattles. A 'rattle' test is not conclusive for an engine like this. It has gone beyond testing PCVs....

But the PCV is rattling still. Just doesn’t see to be vacuuming anything unless I remove the valve and use only the hose. However I have come to the conclusion that I might as well just rebuild the engine.

 

[Brandenthepilot]

Another side note not related to your PCV issues, but is nonetheless very important. Your throttle pressure (kickdown) linkage is adjusted very poorly. The throttle pin on the carburetor should be at the rear most of the slot in the linkage so that as soon as the throttle is opened, it begins to push the kickdown linkage back. As it is now, the transmission is not getting proper line pressure when it should be. That will eventually end the life of your transmission if it's not already damaged it.

I know it is an absolute disaster. Never messed with a carburetor/intake before, so I’ve been reading more and more about it. I’ll try to get it done today and most some pics if you don’t mind helping.

 

[middleagecrisis]

Before you decide to pull the engine, run a compression test and post the numbers. You should have no more than a 10% variance between the cylinders. You could have a trashed valve guide on the cylinder that has the oil on the spark plug. A compression test is still show good cylinder pressure even if you have bad guide(s) that’s causing you to burn oil.You may still have to freshen the heads, but you might not need to totally go through the engine. We’re standing by for the compression numbers.

 

[Brandenthepilot]

Alright so here’s an update from today.

I called the gentleman that sold us the car and got some details. The car has a 360 that was not original to this car specifically - it was then stroked to a 408. If that helps any.

First - cleaned out the carb and throttle body and really focused on the port that the PCV valve is coming in through. Turned the car on and there was great suction. Let the car warm up and again, started getting some smoke/gasses that the plastic PCV wasn’t helping with. There was then smoke coming from what looked like below the headers.

Second - I ran a warm compression test (I forgot the throttle should be wide open) I’m planning on running one with it open if someone thinks it would average out the numbers below some more. Anyways, here are the numbers. these are give or take a few as my gauge doesn’t have precise markings.

8 - 120 PSI
6 - 125 PSI
4 - 130 PSI
2 - 125 PSI

7 - 135 PSI
5 - 130 PSI
3 - 130 PSI
1 - 135 PSI

With the gap on one side I’m going to assume it might be time for a rebuild?!please let me know your thoughts.

@RustyRatRod I took the time to dial in that kick back link it’s nice and tight now and pushes back perfectly to get the notch on the trans to open up all of the way with the throttle opened up as well.

One questions I wanted to bring up on the distributor - again I never messed around with timing stuff. But on the below picture, I notice there are two number 1’s…. Which one should the first wire be ran based off of?

Thanks you all in advance.

 

[middleagecrisis]

Not knowing a lot about how the motor was built, I won’t comment on the compression numbers. However, one bank being significantly lower than the other tells me it might be head gasket related. If the motor was just plain worn out, you would have low compression numbers, or more variance on all cylinders. It might be time to pull off the one head that has the low numbers and see if you can find evidence of a head gasket failure between six and eight. Posting pictures of the head gasket on here will allow us to see damage that you might not be seeing as obvious. This would also be a good time for you to examine the heads for evidence of oil being pulled in through the intake valve guide. This will show as oily buildup in the bowl area and on top of the valve. Bad rings don’t do this, only bad guides. You may get lucky and only need to do a valve job on your heads. Either way, I think that one head needs to come off at this point. On another note, have you seen any evidence of oil coming out between the block and the head? You said you saw oil smoke coming from underneath the car.

 

[70SwingerGuy]

Not sure why i said carburator, it runs to the passenger side of the intake. Sorry about that.

Actually, it does run to the carb, Ive circled it in the pic, its just above the spacer near the back of the carb

 

[Brandenthepilot]

Not knowing a lot about how the motor was built, I won’t comment on the compression numbers. However, one bank being significantly lower than the other tells me it might be head gasket related. If the motor was just plain worn out, you would have low compression numbers, or more variance on all cylinders. It might be time to pull off the one head that has the low numbers and see if you can find evidence of a head gasket failure between six and eight. Posting pictures of the head gasket on here will allow us to see damage that you might not be seeing as obvious. This would also be a good time for you to examine the heads for evidence of oil being pulled in through the intake valve guide. This will show as oily buildup in the bowl area and on top of the valve. Bad rings don’t do this, only bad guides. You may get lucky and only need to do a valve job on your heads. Either way, I think that one head needs to come off at this point. On another note, have you seen any evidence of oil coming out between the block and the head? You said you saw oil smoke coming from underneath the car.

The valve covers do have some oil residue on them but I figure it might have been from the oil being blown out of the oil breather.

I’ll break into the headers tomorrow, I’m off so have plenty of time to do it. I’ll take as many pics and I can if the process. There is a small amount of oil underneath the car - but when I got under there and look at it I was convinced it was the oil pan that needed to be worked on. Wanted to get this issue squared away and figure that out later. Lol

I might decide to just pull the whole engine. I don’t want to, but if it’s best for the car then I might as well do it.

 

[RustyRatRod]

Generally speaking, the correct port for the PCV is on the carburetor. The intake manifold port is usually where the power brake booster hose installs, if it is equipped with power brakes.

 

[70SwingerGuy]

Generally speaking, the correct port for the PCV is on the carburetor. The intake manifold port is usually where the power brake booster hose installs, if it is equipped with power brakes.

@RustyRatRod , check my post a couple up, he actually does have it attached to the carb, he was just mistaken by correcting himself

 

[Swinger 340]

Before you decide to pull the engine, run a compression test and post the numbers. You should have no more than a 10% variance between the cylinders. You could have a trashed valve guide on the cylinder that has the oil on the spark plug. A compression test is still show good cylinder pressure even if you have bad guide(s) that’s causing you to burn oil.You may still have to freshen the heads, but you might not need to totally go through the engine. We’re standing by for the compression numbers.

You can change the valve seals without removing the heads. You just need a good compressor. I have done that several times. Just a note, after reading several comments, no one mentioned the PVC should be connected to the carb base and not "FULL" vac from the intake manifold, that is usually for the brake booster. I'm surprise the motor dose not run ruff at low RPM's, when you run the vac line into the valve cover without the PVC. The PVC is design to cut down the amount of vac being drawn from the valve cover. If you are getting blowby with the PVC hooked up, then you have an issue, as some here touched on. Blowby, without the PVC hooked up, I believe is normal. Again, as mentioned by others, do your checking before tearing apart your motor.

 

[Brandenthepilot]

You can change the valve seals without removing the heads. You just need a good compressor. I have done that several times. Just a note, after reading several comments, no one mentioned the PVC should be connected to the carb base and not "FULL" vac from the intake manifold, that is usually for the brake booster. I'm surprise the motor dose not run ruff at low RPM's, when you run the vac line into the valve cover without the PVC. The PVC is design to cut down the amount of vac being drawn from the valve cover. If you are getting blowby with the PVC hooked up, then you have an issue, as some here touched on. Blowby, without the PVC hooked up, I believe is normal. Again, as mentioned by others, do your checking before tearing apart your motor.

I appreciate the info! - do the compression numbers look normal?

 

[RustyRatRod]

I appreciate the info! - do the compression numbers look normal?

I think they've even enough for what you're doing. I wouldn't worry with that end of it. Just tune it the best with what you have. A good loose ignition curve will help tremendously.

 

[AJ/FormS]

Com-on guys look where the PCV goes onto the carb!
That is NOT correct.

 

[RustyRatRod]

Com-on guys look where the PCV goes onto the carb!
That is NOT correct.

On that style Holley, that's the only large manifold vacuum attachment. So yes, it's correct.

 

[nutz]

if it was sitting a while could be some pitting on the cylinder walls
would bore scope it