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Discussion Starter #1 (Edited)
I've been dealing with this wonderful problem recently, and prayed it was just valve stem seals. The smoke doesn't show up until the engine is warmed up. The smoke is white with maybe a slight blue tint on there, everyone else is saying its just white, I personally think it looks a bit blue. Smoke would get worse when gas pedal is depressed. There isn't any water in the oil and I don't see any cracks on the block from the outside. First time I found the problem I had it idling for a while and a lot of water seemed to come out of the exhaust.

Anyways, I open her up and it looks like the seals are still new from the previous owner. Turns out they didn't lie about an engine rebuild, well so far so good at least haven't looked further into the engine. What I did notice though is that one of the pushrods had gunk on it while all the others did not. What is this an indicator of? Could it be the possible reason why I might be having a bit of an oil leak?

I appreciate any help or ideas as to what it could be, I'll have some photos added to show, and I really wanna get her back on the road!

Extra info:
3spd manual transmission
been a while since the engine rebuild (35k-ish)and it was running fine up till now.
 

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It sounds like the rings haven't sealed on the cylinder walls. If you have pure white smoke, it points to automatic trans fluid getting into the exhaust. Are you leaking oil or possibly sucking it up through your PCV valve? Make sure your PCV is working and the breather on the opposite head isn't clogged.
 

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^^^^^^^ Previous owner had the 302 rebuilt and had the wrong rings installed. They never seated properly, which required me to pull the engine and re-ring after only 5000 miles.
 

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Discussion Starter #4
I'm sorry I didnt put enough info, its been 35k since the engine rebuild and there was no smoking problems before that, I sure hope that isn't a possible problem after this long. Also its a 3spd manual haven't touched the transmission fluid yet though, not sure how that thing's health is yet.

The pcv valve looks like it has a lot of oil on the bottom of it, the breather on the other side is open and is normally connected via tube to the air box.
 

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There is no way for transmission fluid to get inside the combustion chamber unless you put it in the gas tank or pour it in the carb...
Do you have to put water or coolant in the radiator from time to time? That would indicate water getting into the combustion chamber.
Take off your oil cap and PCV valve and look at them for any milky brownish mess in them, or on your dipstick after it has been off for a while. That would indicate water getting into the crankcase.
You can have your cooling system pressure checked and "sniffed" to see if combustion exhaust gases are going into your cooling system.
It is possible you have a bad head gasket, a cracked head, or a cracked block, especially if it has sat a long time and corrosion has taken its toll or an improper coolant ratio led to freezing and a freeze plug didn't do its job.
 

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Since we can’t really rely on the color of the smoke since there seems to be some debate, does it smell like burning oil? It has a very distinctive smell. If not, you’re burning water. My solution would be to put new gaskets on the intake, heads, and water pump. A little trick that can be used is to spray starting fluid around the intake and other engine areas. If everything is correct, it shouldn’t affect anything. If the engine starts to rev up though, you’ve got a blown gasket.
 

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Put a sheet of cardboard under the car and park it overnight and see what's on it in the morning... but DON'T MOVE THE CARDBOARD. If there's any sign of a leak, you'll be able to see where it's dripping from and follow the trail of whatever is leaking to where it's leaking from.
My initial guess is a blown head gasket, but for me back in 2005 it was a crack in the block... and, believe it or not, I patched it with JB Weld. Figured I'd get the rest of the summer out of it.
It held til 2015.
JB rocks!!
I have another engine now, but yeah... JB.
 

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That doesn't look bad, at all. A couple things... do you notice any oil consumption? One thing that CAN explain white "smoke" along with more water out the tailpipes is a higher ethanol content in the fuel and its absorption of water. Ethanol is hygroscopic so if the ethanol content goes up and the humidity is high or the gas station tanks have a "water issue" that ends up in the fuel and when the mixture gets ignited the water turns to steam, condenses in the exhaust and you get water vapor and liquid out the tailpipe.
 

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White smoke is coolant. Start with pressure testing the cooling system and that will usually show a leak if there is one. There is another test that uses a chemical that reacts to exhaust in the cooling system but it isn't used a whole lot as it's pricey for what it is. I would test it cold and then if it passed test it again after the engine is hot being careful not to blow hot water all over yourself.
Water coming out the tailpipe is normal as water is one of the byproducts of perfect combustion. You will notice that fuel injected cars usually have quite a bit of water even after initial condensation has burned out of the exhaust.
 

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I put my money on the comments pf the previous two posters (Woodchuck & elcam84), both valid in my opinion.
 

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I put my money on the comments pf the previous two posters (Woodchuck & elcam84), both valid in my opinion.
+1.
White smoke is usually water or coolant. When the car is first started its usually just condensation and not a problem. If the car is warmed up and smoking white then it's likely water from somewhere - either in the gas or a coolant leak into a cylinder. Pressure testing the cooling system is an easy way to find out if there is a leak somewhere. I think you can get a loaner pressure checker kit at your local parts store.
Edit: If coolant/water is entering the combustion chamber you won't necessarily see it in the oil.
 

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Discussion Starter #12
Alright, so it smells like burnt oil (and it doesn't smell sweet like coolant would).

I've done a compression check already, all consistent number and it held pressure just fine. Did that with both a warm and cold engine.

usually when I try to remove radiator cap (when it's cold I wouldnt dare try to open is when its hot) there's still pressure and coolant tends to shoot out as soon as i open it. I was worried that may have meant it was overfilled so I removed some coolant and it still occurs. Maybe I didn't remove enough?

There are no coolant or oil leaks over night or once warmed up.

When it does start to smoke though, the smoke will eventually start to come from the breather cap and the pcv valve if I open it.

And what would explain my one pushrod being gunked up significantly more than the others? though it may not be much gunk in the first place.
 

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Take a video or at least a picture of the smoke and post it here. Sounds like a head gasket issue.
 

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If it's oil you're burning and the compression check is ok it's a very good thing as it eliminates a lot of issues. A compression check and a radiator pressure check eliminates (I think) most head gasket problems.

First, check to make sure the PCV valve is working correctly... does it rattle or is it stuck open so that oil from under the valve covers can be sucked into the carb.

If it is not a bad PCV valve it is likely that you are getting oil into the combustion chamber via:
(1) the intake values - either worn valve guides or bad valve seals. But if it is either of these you usually see blueish smoke mainly at startup after a night of sitting as the engine sucks in the small pool of oil that has developed overnight.
(2) Internal leaks from the intake manifold-to-head gasket. Oil vapor from the lifter valley is getting sucked into the combustion chamber at the interface between the intake and head. Possibly when the engine heats up, uneven expansion causes the gasket not to seal, but only when hot. Unfortunately, I don't really know any good way of determining whether this could be the problem.


Re: "...there's still pressure and coolant tends to shoot out as soon as i open it. I was worried that may have meant it was overfilled so I removed some coolant and it still occurs. Maybe I didn't remove enough?"
It also may be that there are some air pockets in the cooling system. Has the cooling system been "burped" sufficiently?
 

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Discussion Starter #15
I got a new pcv valve anyways from my last order of things, I'm probably gonna take the intake off, change all the gaskets, put everything back, and check through everything again. Or should I just go ahead and take the extra step and change the head gaskets? Problem is I don't have the real estate atm to remove the engine at my house. Anyone ever remove the heads without removing the engine? seems rather tight in there.
 

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I got a new pcv valve anyways from my last order of things, I'm probably gonna take the intake off, change all the gaskets, put everything back, and check through everything again. Or should I just go ahead and take the extra step and change the head gaskets? Problem is I don't have the real estate atm to remove the engine at my house. Anyone ever remove the heads without removing the engine? seems rather tight in there.
You can 100% take the heads off without removing the engine. I broke a valve keeper which dropped the valve down into the piston. Long story short, I just decided to upgrade to Trick Flow aluminum heads.
 

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I got a new pcv valve anyways from my last order of things, I'm probably gonna take the intake off, change all the gaskets, put everything back, and check through everything again. Or should I just go ahead and take the extra step and change the head gaskets? Problem is I don't have the real estate atm to remove the engine at my house. Anyone ever remove the heads without removing the engine? seems rather tight in there.
Here are my thoughts about the head gaskets.

The head gasket seals and isolates the (1) combustion chambers, (2) coolant passages and (3) oil passages (I think the only place where oil passes through the head gasket is where it drains from the top of the head under the valve cover back down to the block??). So if the compression test passes and a radiator pressure test passes (-> no coolant leaks anywhere), in theory, you should not have to change the head gaskets.

The only caveat to this that I can think of is if there is some heat-related issue where the gasket starts to leak when the engine is hot - you may want to check to make sure all the head bolts are torqued to spec. It also might be (hopefully, not) a crack somewhere on the head/block that is causing the problem when hot.

One benefit in removing the heads is that you can check the valves while you have them off. You can also check to make sure the heads and the top of the block are planar.

The only other way to get oil into the combustion chamber is from (1) valve stems/seals (2) past the piston rings and (3) from an intake-to-head gasket leak into the lifter valley.

One final note, if you're burning a lot of oil you should see some signs of fouling on some of your spark plugs.
 

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Discussion Starter #18
Here are my thoughts about the head gaskets.

The head gasket seals and isolates the (1) combustion chambers, (2) coolant passages and (3) oil passages (I think the only place where oil passes through the head gasket is where it drains from the top of the head under the valve cover back down to the block??). So if the compression test passes and a radiator pressure test passes (-> no coolant leaks anywhere), in theory, you should not have to change the head gaskets.

The only caveat to this that I can think of is if there is some heat-related issue where the gasket starts to leak when the engine is hot - you may want to check to make sure all the head bolts are torqued to spec. It also might be (hopefully, not) a crack somewhere on the head/block that is causing the problem when hot.

One benefit in removing the heads is that you can check the valves while you have them off. You can also check to make sure the heads and the top of the block are planar.

The only other way to get oil into the combustion chamber is from (1) valve stems/seals (2) past the piston rings and (3) from an intake-to-head gasket leak into the lifter valley.

One final note, if you're burning a lot of oil you should see some signs of fouling on some of your spark plugs.
And I completely agree with you with the head gasket info you stated.

Not a bad idea to go ahead and retorque the bolts though

Ah yes, I did find some dark carbon fouling on my plugs, and thats part of the reason I feel it is oil. I can't rule out that maybe it was gas though because I was running rich right before all this. Just did my tune up and then I started having these problems.
 

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And I completely agree with you with the head gasket info you stated.

Not a bad idea to go ahead and retorque the bolts though

Ah yes, I did find some dark carbon fouling on my plugs, and thats part of the reason I feel it is oil. I can't rule out that maybe it was gas though because I was running rich right before all this. Just did my tune up and then I started having these problems.
One more thing (sorry if this is obvious)... if you are getting fouling on all your plugs ~equally then it's likely not a head gasket problem (or valve stems, cracks, etc) as that should be localized to one or two plugs. And the only place where I could even conceive of a head gasket causing a problem with oil being burnt is one of the cylinders near the ends of the heads where the oil drains back into the block.
 

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Discussion Starter #20 (Edited)
A little update on this, so I had retorqued the heads and intake manifold. Looks like it still smokes the same. Next step, planning on digging under the intake manifold. Going to order the seals for that now.

I didn't end up doing much when removed the valve covers, since the seals still looked new. I did notice that the valve stem seals weren't those umbrella type seals. Could maybe the shop it was taken to have chosen the wrong type of seals? or are those seals with the metal tension ring around it just fine?
 
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