Oil burn cloud on engine deceleration

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WSUTARD said:
Also. I’m seeing a lot of condensation coming out of my air compressor end. Should I be using a water separator or is the condensation ok going into the cylinder?
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I would not worry too much about it... assuming you're gonna fire it back off as soon as you are done.
 
Well I have hit a snag. Can’t get the air QD in on the #5 or 7 cylinders due to the headers. Gotta grab some nylon rope to try the rope trick.

However, all these seals I’m taking off are basically new. I have started to skip the exhaust seals. I’m not sure this is my issue.
 
WSUTARD said:
Well I have hit a snag. Can’t get the air QD in on the #5 or 7 cylinders due to the headers. Gotta grab some nylon rope to try the rope trick.

However, all these seals I’m taking off are basically new. I have started to skip the exhaust seals. I’m not sure this is my issue.
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Are you leaning towards "not sure it's a seal issue"?
 
Yeah. It’s he next thing. Which would be rings. But I’m going to finish here then test when it stops raining.
 
I found a smoke issue when a PCV was replaced with a different mfg. Once I removed the hose from the carb and ran it to the air cleaner, the smoke went away. Try to choke down the hose by inserting a smaller hose in your PCV hose.
 
WSUTARD said:
Well I have hit a snag. Can’t get the air QD in on the #5 or 7 cylinders due to the headers. Gotta grab some nylon rope to try the rope trick.

However, all these seals I’m taking off are basically new. I have started to skip the exhaust seals. I’m not sure this is my issue.
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If you run the piston to TDC when you have the springs off you can take the air pressure off the cylinder and check the guide for wear by the close but not perfect wiggle test.
 
All the seals were basically new. None showed any signs of wear and they were all pliable.

Next step is to take it to my mechanic for a leak down test.

Here is a video of the play the valve stem has in the guide. I’m not sure if this is within tolerance or not.
 
Those do not look like umbrella seals. Do you know if they were installed with protective sleeves over the valve ends first? A little burr will mess up what looks like a Teflon seal to me.
 
WSUTARD said:
All the seals were basically new. None showed any signs of wear and they were all pliable.

Next step is to take it to my mechanic for a leak down test.

Here is a video of the play the valve stem has in the guide. I’m not sure if this is within tolerance or not.
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On a cast iron guide that is just about as loose as I'd run it without a positive seal.
 
I've not typically seen heavy oil smoke like you reported from your tests on page 2 of this thread just from guide wear. Your guide wear is what I would call moderate. But I can not 100% rule it out; we all see new stuff everyday!

No smoking with hard throttle would typically rule out rings; it all points to the intake tract. I'd still be more inclined to look at the intake gaskets.

BTW, back on page 2 when you tested with no PCV and had lots of smoke under downhill deceleration, was the PCV just gone and the hose to the carb sealed off, or was the hose to the PCV still in the valve cover? Just checking to make sure I understand the test and what the results mean.
 
nm9stheham said:
I've not typically seen heavy oil smoke like you reported from your tests on page 2 of this thread just from guide wear. Your guide wear is what I would call moderate. But I can not 100% rule it out; we all see new stuff everyday!

No smoking with hard throttle would typically rule out rings; it all points to the intake tract. I'd still be more inclined to look at the intake gaskets.

BTW, back on page 2 when you tested with no PCV and had lots of smoke under downhill deceleration, was the PCV just gone and the hose to the carb sealed off, or was the hose to the PCV still in the valve cover? Just checking to make sure I understand the test and what the results mean.
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I removed the PCV from the valve cover but left it attached to carb since my tuning was setup with the additional air coming from the PCV.

I’m not sure how it could still be the intake gaskets as they are new with proper ultra grey around the ports.
 
WSUTARD said:
I removed the PCV from the valve cover but left it attached to carb since my tuning was setup with the additional air coming from the PCV.

I’m not sure how it could still be the intake gaskets as they are new with proper ultra grey around the ports.
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I've seen intake manifolds that were machined wrong from the factory. Also seen them that have been machined wrong but other shops.
 
WSUTARD said:
I removed the PCV from the valve cover but left it attached to carb since my tuning was setup with the additional air coming from the PCV.

I’m not sure how it could still be the intake gaskets as they are new with proper ultra grey around the ports.
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Gotcha.... just thinking what is most likely. Very good on the PCV test setup; that took it out of the picture. Let us know if the seals help.
 
Seals did not help. I’m still getting the same amount of smoke on downhill deceleration.

Regarding the intake. It has sealed up before and has not been altered since. It is an aluminum Edelbrock.

Thinking out of the box here. When I remove the intake, which I have done about 4 now, I use a fine scotch bright pad (grey from Oreily auto) to clean the head and I take surfaces from remaining gasket and RTV. Maybe I have removed just enough of the surface that it’s now causing gasket issues? I highly doubt it but maybe ¯\_(ツ)_/¯

I have an appointment at my mechanic for a leak down test in a week. However, I’m not sure what it will tell me. If this issue was rings I would assume I would be seeing smoke all the time. Same with cracked heads of head gasket issues. He fact that it’s just on downhill deceleration makes this weird. I guess it could be happening on flat deceleration as well but there just isn’t enough time to build up the smoke?

On the downhill deceleration the smoke steadily builds. When I first decelerate there isn’t any smoke. Then as I go longer more smoke comes out. Finally when I stop here is a good amount coming out.
 
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Dang, 4 times? You sure the bolts are torqued enough? I would probably be frustrated enough at that point to go buy a bore-scope to check the intake seal... Drive it and decel down a long hill and after it starts smoking for a bit just pull over and put the scope down the carb.

Was this last test also with the PCV disconnected?
 
MOPEkidD-3 said:
Dang, 4 times? You sure the bolts are torqued enough? I would probably be frustrated enough at that point to go buy a bore-scope to check the intake seal... Drive it and decel down a long hill and after it starts smoking for a bit just pull over and put the scope down the carb.

Was this last test also with the PCV disconnected?
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Well 4 times since owning the car for a year and half, not for this issue.

The PCV is connected and was connected for the last test. I figured it wasn’t an issue since it smoked with or without.
 
The smoke on downhill deceleration is a classic symptom for intake side leaks so it is not really at all weird; the vacuum is highest with the throttle closed and engine braking going on and engine braking is the most sustained going downhill. Put a vacuum gauge on it and look at the vacuum under those conditions and I bet you will see well over 20 in of vacuum even with your cam. That will suck oil through any small opening into the intake tract: seals, guides, intake manifold leaks.
 
WSUTARD said:
Well 4 times since owning the car for a year and half, not for this issue.

The PCV is connected and was connected for the last test. I figured it wasn’t an issue since it smoked with or without.
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Is your PCV on the passenger or drivers valve cover?
 
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