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White Exhaust Smoke

One method to determine if a head gasket has failed from the coolant passage to the cylinder: warm engine at idle with radiator cap off, when engine reaches idle operating temp ( thermostat has opened ), observe coolant inside radiator for any air bubbles.
 
Not to my knowledge no. I bought the car from a mechanic who fixes up barn finds. I am assuming that he did what was necessary to sell.
If I was in your situation I would remove all of the spark plugs for evidence of a coolant leak. The chances are higher of a leak in the cylinder at the back of the engine and the cylinder at the front of the engine, I would remove those 2 spark plugs first. (Just my personal preference)
 
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If I was in your situation I would remove all of the spark plugs for evidence of a coolant leak. The chances are higher of a leak in the cylinder at the back of the engine and the cylinder at the front of the engine, I would remove those 2 spark plugs first. (Just my personal preference)
Thanks. I am going to run the car while leaving the radiator cap off until the thermostat opens up first and see if I can detect any bubbles in the coolant. If I see any I am planning on pulling the spark plugs. I am guessing that I am going to see bubbles due to the fact that the white smoke seems to intensify after idling for a minute or two. However I have not had excessive coolant loss. Maybe it is a small crack in the gasket? Not sure. I will report back.
Thanks for all the help.
 
How far are you driving it? You sure it just isn't warmed up completely? Most cars put out steam from the exhaust for a mile or so after a cold start. You have added ZERO coolant in 6 months?
And what do you mean by a crankcase gasket leaking oil into the combustion chamber? Never heard of such a gasket. You might have oil getting in past old valve stem seals that are cracked, but that should give blue smoke. And that smoke usually stops after it runs for a bit unless those seals are in really bad shape.
Okay, took the radiator cap off and let the engine run at idle for 20 minutes. I observed the temperature gauge and go up and still no bubbles! Still getting a bit of white smoke. I am going to really run her out this weekend and pay attention to the radiator. Also still no antifreeze in the oil.
 
Coolant leaking into the chambers should produce steam, not smoke. I still think you are getting a little oil past the valve stem seals. Oil smoke is such a very light blue, that you can easily mistake it for white if it's just a little bit. It's a slant 6, and could possibly still have the old original valve stem seals. My 64 Fury 361 still had the originals with 90K miles on it, and I was getting some oil smoke. I replaced the seals and I have NONE now.
Keep a check on your oil and coolant levels, and just drive and enjoy the car.
 
Coolant leaking into the chambers should produce steam, not smoke. I still think you are getting a little oil past the valve stem seals. Oil smoke is such a very light blue, that you can easily mistake it for white if it's just a little bit. It's a slant 6, and could possibly still have the old original valve stem seals. My 64 Fury 361 still had the originals with 90K miles on it, and I was getting some oil smoke. I replaced the seals and I have NONE now.
Keep a check on your oil and coolant levels, and just drive and enjoy the car.
Thanks bud.
 
Checking spark plugs is a good idea. If coolant is getting into a chamber the plugs get 'steam cleaned' & look whiter/cleaner.

I asked this earlier: power brakes?
 
Checking spark plugs is a good idea. If coolant is getting into a chamber the plugs get 'steam cleaned' & look whiter/cleaner.

I asked this earlier: power brakes?
Will do. Drum brakes. I assume my breaks are manual. How can I tell?
 
My dear-departed dad would tell me look at the simple things first. As posted, there are a wealth of checks you can make that are not complex before getting more invasive and expensive. It seems that you haven’t obtained information on the overall condition of the motor, or what was done to it to get it back on the road; but engine seems to run fine? That's good.

Do some simple checks to see how the engine is tuned using an rpm, vac gauge and timing light. This is to rule out possible causes. All might be fine; but IMO, some things to ASSURE me it’s right. There could be some accumulation of carbon in the motor, you can run an engine cleaner through it. Lol, if you haven’t seen enough smoke yet, you will doing this. I’ve used marvel mystery oil (lot’s of other products for this including seafoam I’ve used) adding a few ounces of this to the oil and gas to burn off deposits. Run it a few hundred miles then change the oil/filter. Add it to the fuel over a few tanks of gas. Who knows, if you’re running unleaded gas and the valve seats weren’t changed on the motor, this could be a gremlin. I used a lead additive in one of my motors until installing hardened seats on the rebuild.

Could this be the problem or remedy? Maybe no; but again if I don’t know what’s been done to the motor some guy fixed – yet no obvious ills that point to more major issues, simple things to.
 
My dear-departed dad would tell me look at the simple things first. As posted, there are a wealth of checks you can make that are not complex before getting more invasive and expensive. It seems that you haven’t obtained information on the overall condition of the motor, or what was done to it to get it back on the road; but engine seems to run fine? That's good.

Do some simple checks to see how the engine is tuned using an rpm, vac gauge and timing light. This is to rule out possible causes. All might be fine; but IMO, some things to ASSURE me it’s right. There could be some accumulation of carbon in the motor, you can run an engine cleaner through it. Lol, if you haven’t seen enough smoke yet, you will doing this. I’ve used marvel mystery oil (lot’s of other products for this including seafoam I’ve used) adding a few ounces of this to the oil and gas to burn off deposits. Run it a few hundred miles then change the oil/filter. Add it to the fuel over a few tanks of gas. Who knows, if you’re running unleaded gas and the valve seats weren’t changed on the motor, this could be a gremlin. I used a lead additive in one of my motors until installing hardened seats on the rebuild.

Could this be the problem or remedy? Maybe no; but again if I don’t know what’s been done to the motor some guy fixed – yet no obvious ills that point to more major issues, simple things to.
I am going to go ahead with the spark plug inspection. I am also planning on doing a carb rebuild as I know for sure that my fuel bowl is leaking and needs a new gasket.
If I do go ahead with the rpm and timing gauge, how can I apply this data to fine tuning the engine? I have a shop manual and I assume the ideal engine timing and stats would be listed there. Would these kinds of issues result in the exhaust smoke issue?
Thanks.
 
Yes, the specs are in the FSM, timing, dwell, gap, rpm, setting carb – tuning info assuming few modifications to engine – stock specs. A motor out of spec can emit exhaust smoke/smell. Again, this is my 2 cents on things I’d check out, since you may not know what has been done to the engine and its condition. You’ve done a few things to find no serious issues, no loss of oil or coolant, no milky way, no leaks. A carboned up valve could be a culprit (I had luck on one of my engines running marvel through it for a few hundred miles). Have you heard any strong ticking noises in the motor? Same deal with a cylinder, could be crapped up (carbon). Looking at the plugs can offer some indication. If you can still contact the guy that worked on it, could ask him what he did on the motor. Checking your fuel bowl, look for indication of gumming up. Rebuilding carb could be a good idea; but I’d run cleaner through it first then tuning. He might a had some old parts lying around he used, or possibly some that are not correct for the motor. My guess is the goal wasn’t spending any more on repairing or rebuilding than having it run decent and selling. Again, I’m not sure all this is going to solve the problem, but assuring it’s tuned right, no skanked parts, and given a clean out before I’d start tearing it down. I held off for a few years before I rebuilt my last motor as it ran good enough. The rebuild in my case was to beef it up not because it didn't run decent.
 
Yes, the specs are in the FSM, timing, dwell, gap, rpm, setting carb – tuning info assuming few modifications to engine – stock specs. A motor out of spec can emit exhaust smoke/smell. Again, this is my 2 cents on things I’d check out, since you may not know what has been done to the engine and its condition. You’ve done a few things to find no serious issues, no loss of oil or coolant, no milky way, no leaks. A carboned up valve could be a culprit (I had luck on one of my engines running marvel through it for a few hundred miles). Have you heard any strong ticking noises in the motor? Same deal with a cylinder, could be crapped up (carbon). Looking at the plugs can offer some indication. If you can still contact the guy that worked on it, could ask him what he did on the motor. Checking your fuel bowl, look for indication of gumming up. Rebuilding carb could be a good idea; but I’d run cleaner through it first then tuning. He might a had some old parts lying around he used, or possibly some that are not correct for the motor. My guess is the goal wasn’t spending any more on repairing or rebuilding than having it run decent and selling. Again, I’m not sure all this is going to solve the problem, but assuring it’s tuned right, no skanked parts, and given a clean out before I’d start tearing it down. I held off for a few years before I rebuilt my last motor as it ran good enough. The rebuild in my case was to beef it up not because it didn't run decent.
Thanks Ron, no ticking. I will do some more inspecting and tinkering around and then possibly try the cleaner route. I am a bit reluctant with the cleaner as I just changed the oil a month ago, but we will see what kind of $ I have.
Regardless I will get back to you and let you know what kind of progress I am making. Thanks for all the info again.
 
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