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My 427 started smoking from drivers side, I checked no oil in water or water in oil, decided to do compression check passenger sides 200 and drives side close to 210 each cylinder found oil to be dirty and #1 and 3 plugs in this condition Changing plugs and oil today to see if that helps, but why would rating be so high or is that normal, maybe valve seals?
Smoking black blue, your plugs look pretty black to me.
Blue smoke part time valve stem seals
Blue smoke all the time rings
Black smoke rich = looking at them plugs
Rating, do you mean compression readings = maybe carbon buildup in chambers. be more concerned if your readings were more than that.
Run something thru it to clean the intake, valves.
Shop I worked at used automatic trans fluid
Smoking black blue, your plugs look pretty black to me.
Blue smoke part time valve stem seals
Blue smoke all the time rings
Black smoke rich = looking at them plugs
Rating, do you mean compression readings = maybe carbon buildup in chambers. be more concerned if your readings were more than that.
Run something thru it to clean the intake, valves.
Shop I worked at used automatic trans fluid
yes my valve chambers last year were pretty much carbon filled when I got the car , I ran BG109 and 44K cleaner thru the engine, smoke looks white, but no antifreeze loss or milky oil will see how it does after another oil change waiting on Lucas Hot Rod oil today
yes my valve chambers last year were pretty much carbon filled when I got the car , I ran BG109 and 44K cleaner thru the engine, smoke looks white, but no antifreeze loss or milky oil will see how it does after another oil change waiting on Lucas Hot Rod oil today
unless you get hotter plugs, it is going to get worse.
even then oil may just be too much.
what plugs are you running?
The drivers side bank of cylinders is running hotter.
You have oil deposits on which # plugs? 1-3-5-7?
An Intake Gasket Leak will make a cylinder run lean, (hotter) and will burn oily mist from the lifter valley.
Forget spraying any flammable substance around the upper Intakes gasket. That seldom works. The fan blows propane, carb cleaner, etc away from the area.
Intake gaskets leaks are often on the bottom side of the gasket at the lifter valley. Or, undetectable.
Hook up a vacuum gauge to full manifold vac. A bouncing needle is often an Inlet vacuum leak. Either valve seat or Intake gasket.
The drivers side bank of cylinders is running hotter.
You have oil deposits on which # plugs? 1-3-5-7?
An Intake Gasket Leak will make a cylinder run lean, (hotter) and will burn oily mist from the lifter valley.
Forget spraying any flammable substance around the upper Intakes gasket. That seldom works. The fan blows propane, carb cleaner, etc away from the area.
Intake gaskets leaks are often on the bottom side of the gasket at the lifter valley. Or, undetectable.
Hook up a vacuum gauge to full manifold vac. A bouncing needle is often an Inlet vacuum leak. Either valve seat or Intake gasket.
1 and 3 were fouled 1 more than 3 the rest were normal, I did put new intake gasket last year which is is when I noticed the carbon deposits, I have drained the old oil and do have vacuum gauge once the oil arrives today I will start and check for leaks.
Go around that end of the intake and snug the bolts down.....are they loose? Pull the carb and stick a scope down those to ports.......do you see any oil? Scopes are super cheap these days and can be run by your smartphone.
Hotter plug is never a fix unless way too cold of a plug was used to begin with.........
The suggestion on the resistance of those two plug wires is nothing to rule out........
It could be an intake leak but what does the vacuum gauge say? Smooth steady gauge rules that out.......
200-210psi compression is damn good.....no issues there......the higher your overall compression, the more a bad cylinder will stick out......you are less than 6%....great.
jbradley02
H-m-m-m-m-m. I like quotes: Quotes reveal history of an engine and help diagnose.
I did put new Intake Gaskets on recently. That's when the carbon deposits showed up too.
Before wrenching on the Intake removal, try a vacuum reading just to be sure.
This is an easy fix if that is the problem. Take a Sharpie and make a little mark on the distributor base flange and onto the Intake for future reference of timing.
Set the crank at #1 TDC. You only have to drain part of the coolant. Pull dizzy, remove throttle cable & carb, upper Rad hose, heater hose, some vacuum lines.
You will only be out some new gaskets < $20 + some sealant $10.
jbradley02
H-m-m-m-m-m. I like quotes: Quotes reveal history of an engine and help diagnose.
I did put new Intake Gaskets on recently. That's when the carbon deposits showed up too.
Before wrenching on the Intake removal, try a vacuum reading just to be sure.
This is an easy fix if that is the problem. Take a Sharpie and make a little mark on the distributor base flange and onto the Intake for future reference of timing.
Set the crank at #1 TDC. You only have to drain part of the coolant. Pull dizzy, remove throttle cable & carb, upper Rad hose, heater hose, some vacuum lines.
You will only be out some new gaskets < $20 + some sealant $10.
Regarding last suggestions smoke was not occurring until recently, last year before car put away was fine, but I did vacuum check from distributor port got 15 also on intake same, should the ported be 0 at idle? Accelerated then match intake? , still smoking after plugs and Lucas hot rod oil change, I say white smoke but could be gray, taking Friday to guy at Garage that races and builds engines for his take on it then will revert
I'm sure someone will tell me if I'm wrong, but doesn't white smoke indicated a head gasket leak or somehow coolant getting into combustion chamber? Are you seeing hotter coolant temps or overheating at all? I'm not sure if it's possible for this to be the case and not show up on a compression test. Maybe a leak down test will show if this is the case and you could check for bubbles in the coolant. If it still seems to run okay and have a decent vacuum reading, maybe it's a small head gasket leak- enough to show smoke but not effect performance. Keep an eye on coolant level. When I had a small head gasket leak, it only went into combustion chamber and caused white smoke. It took a bit for coolant level to drop to the point where it started overheating. I know the guys chiming in are giving you great advice- I always learn more when I read their posts!
I'm sure someone will tell me if I'm wrong, but doesn't white smoke indicated a head gasket leak or somehow coolant getting into combustion chamber? Are you seeing hotter coolant temps or overheating at all? I'm not sure if it's possible for this to be the case and not show up on a compression test. Maybe a leak down test will show if this is the case and you could check for bubbles in the coolant. If it still seems to run okay and have a decent vacuum reading, maybe it's a small head gasket leak- enough to show smoke but not effect performance. Keep an eye on coolant level. When I had a small head gasket leak, it only went into combustion chamber and caused white smoke. It took a bit for coolant level to drop to the point where it started overheating. I know the guys chiming in are giving you great advice- I always learn more when I read their posts!
I'm sure someone will tell me if I'm wrong, but doesn't white smoke indicated a head gasket leak or somehow coolant getting into combustion chamber? Are you seeing hotter coolant temps or overheating at all? I'm not sure if it's possible for this to be the case and not show up on a compression test. Maybe a leak down test will show if this is the case and you could check for bubbles in the coolant. If it still seems to run okay and have a decent vacuum reading, maybe it's a small head gasket leak- enough to show smoke but not affect performance. Keep an eye on coolant level. When I had a small head gasket leak, it only went into combustion chamber and caused white smoke. It took a bit for coolant level to drop to the point where it started overheating. I know the guys chiming in are giving you great advice- I always learn more when I read their posts!
Thank You what you have said I have tried before asking and again afterwards which is the reason I am taking Friday to get a definitive answer then If I have to remove the heads for head gasket I will also have valve job, seals etc done, hoping it is as simple as that and not lower because then I will just break out the Chevelle for the summer and get the engine rebuilt so fingers crossed
You may not have chosen the best place to tap in a vacuum gauge, but if the needle was steady then you get the jest of the test.
Its difficult sometimes to classify white smoke or gray smoke out the tailpipe. However, coolant is usually a sweet smell where as oil is, . . . . . . .well it stinks!
I really doubt this is a head-gasket issue, but you can monitor your coolant level.
If you are going to pull the heads and have new stem seals installed, that will eliminate those and a faulty Intake Gasket in the future.
A Compression Test will not show bad stem seals or bad Intake Gasket and not really show a bad head gasket.
A Leak-Down Test will not show bad stem seals or bad Intake Gasket but will show faulty head gasket, rings, valve seats.
Myself, I am still leaning towards a bad Intake Gasket that could allow coolant into a cylinder. Could allow oil into a cylinder. And could foul plugs.
Five out of four people have trouble with fractions.
Five out of four people install Intake Manifold Gaskets incorrectly.
Last edited by HeadsU.P.; Jun 14, 2023 at 07:37 PM.
You may not have chosen the best place to tap in a vacuum gauge, but if the needle was steady then you get the jest of the test.
Its difficult sometimes to classify white smoke or gray smoke out the tailpipe. However, coolant is usually a sweet smell where as oil is, . . . . . . .well it stinks!
I really doubt this is a head-gasket issue, but you can monitor your coolant level.
If you are going to pull the heads and have new stem seals installed, that will eliminate those and a faulty Intake Gasket in the future.
A Compression Test will not show bad stem seals or bad Intake Gasket and not really show a bad head gasket.
A Leak-Down Test will not show bad stem seals or bad Intake Gasket but will show faulty head gasket, rings, valve seats.
Myself, I am still leaning towards a bad Intake Gasket that could allow coolant into a cylinder. Could allow oil into a cylinder. And could foul plugs.
Five out of four people have trouble with fractions.
Five out of four people install Intake Manifold Gaskets incorrectly.
Noted and as I have installed intake gaskets before doesn’t mean it is installed correctly this time
Noted and as I have installed intake gaskets before doesn’t mean it is installed correctly this time
to update mechanic at garage said it is oil smoke, took home and did an attempted leak down test #1 90psi air reads 60 on right gauge #3 cylinder steady but initially heating air out of carb no bubbles in radiator or air out of valve cover, as I am not sure doing this correctly have an appointment next week to get done at garage hoping was my errors and rings not gone but if so will have it dealt with
to update mechanic at garage said it is oil smoke, took home and did an attempted leak down test #1 90psi air reads 60 on right gauge #3 cylinder steady but initially heating air out of carb no bubbles in radiator or air out of valve cover, as I am not sure doing this correctly have an appointment next week to get done at garage hoping was my errors and rings not gone but if so will have it dealt with
You have to make sure both valves are shut......easy way to do this is blow the thumb off each cylinder while a helper bumps the key or a remote bumper like I do.....if you are close to TDC on each cylinder you can take the reading.....
You have to make sure both valves are shut......easy way to do this is blow the thumb off each cylinder while a helper bumps the key or a remote bumper like I do.....if you are close to TDC on each cylinder you can take the reading.....
Jebby
I do have a remote starter just have to get under there and connect, but engine has to be hot right? I can try again this weekend before taking to garage next week as it is supposed to rain tomorrow I have an OTC leak down tester, I am sure the air I initially heard was intake valve was not fully closed, and yes he said it was oil burning smoke
I do have a remote starter just have to get under there and connect, but engine has to be hot right? I can try again this weekend before taking to garage next week as it is supposed to rain tomorrow I have an OTC leak down tester, I am sure the air I initially heard was intake valve was not fully closed, and yes he said it was oil burning smoke
Compression reading
