White tailpipe exhause briefly after starting

[fordfun]

Shortly after start-up there's a great deal of white exhaust smoke coming thru the tailpipe on my 1929 Sport Coupe with Mod. B head & carb. It clears in 2-3 minutes, and is not present while driving. I start the engine with the GAV open 1/2 turn, and close that as soon as the engine runs without stalling (by closing it too early). Closing the GAV seems to have no immediate effect on the smoking. It seems that the longer the car sits between drives, the longer it takes for the smoke to clear. Any thoughts on what's going on here?

Thanks - Bill

[Y-Blockhead]

Is your radiator level going down? White Smoke = Water, Blue Smoke = Oil, Black = Too Rich (GAV open too much).

Maybe you have a head gasket weeping into a cylinder while it sits. Do you have any signs of water in your oil?

[jax55]

Is it actually smoke or could it be steam? Could be from hot exhaust and cool ambient temps creating condensation in the exhaust system.
White smoke indicates water or anti freeze. Are you losing coolant when you check it?
2-3 minutes kind of says condensation to me.. if it were in the cylinder I think it would be gone more quickly.

[tbirdtbird]

be suspicious of a water leak at the head gasket.
steps to follow:
1) do a compression test. Cyls should be within 10%. Example, if highest is 60, lowest should be about 54. Be especially aware of readings on the siamesed cyls; ie 1-2 and 3-4. Post results.

2) re-torque head a couple times. There is tremendous controversy here about whether that should be done hot or cold. Take your pick. I prefer hot, since the studs are expanded (lengthened) when hot and I want all the stretch taken out. To me, if you re-torque cold, then when the engine warms up, the studs lengthen, and now you have less torque (clamping force) than when you started.
However there are those on here for which this (cold) apparently works.

report back

[Mitch//pa]

Does a miss fire occur when the smoke is coming out? Is the oil cloudy / milky? I usually perform a leak down test after I test it with combustion gas dye then do a retorque first if tests prove positive

[iverson]

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sounds like head gaskit maybe you could take out plugs after sitting and before starting and take a look? or hold paper or cardboard over plug holes and spin eng? maybe something will spit out?

[Tom Wesenberg]

If you pull the head be sure to check the new gasket for fit to the head and also fit to the block. You don't want either side of the fire rings to be unsupported, and you don't want any coolant holes open to places they shouldn't go. Since you have a B head on an A block be especially aware of any mismatch as just described.

[CT Jack]

Sounds like a leaking head gasket. Replace it with a copper gasket and torque it to 50#-FT using the proper tightening sequence. Run the engine for about 20 mins letting it get hot. Shut it off and let it completely cool down. Then retorque the head following the proper sequence. Repeat the retorquing procedure several times after running/driving it several times. Retorquing has to be done when the engine is completely cold. Doing this will properly seat the new gasket.

[tbirdtbird]

50 ft-lbs?

[fordfun]

Well I have more information than when I started.

* The cooling system is down a qt.
* No apparent water seen thru plug holes
* Oil does not look milky
* Checked head nuts for torque and all seemed OK (55#)
* I'll do a compression test tomorrow

I've never done a Leak-down test. Can that be done with Compression test gauge or do I need more equipment?

Is it important to test fluid for combustion gases? If so, what do I need for that?

Thanks for all of the good advice. Seems like I'm headed toward pulling the head, which will be a new experience.

[Pete]

Originally Posted by tbirdtbird

2) re-torque head a couple times. There is tremendous controversy here about whether that should be done hot or cold. Take your pick. I prefer hot, since the studs are expanded (lengthened) when hot and I want all the stretch taken out. To me, if you re-torque cold, then when the engine warms up, the studs lengthen, and now you have less torque (clamping force) than when you started.
However there are those on here for which this (cold) apparently works.

report back

You are as full of shit as a Christmas goose!
You need a kindergarten course in metalurgy.

[Deny1950]

Pete instead of insulting the guy why not simply tell him why it should be done cold. may be you could grab a ride with him to the kindergarten when you go for your diplomace class.

[CT Jack]

Yes, the units for torque or moments are Newton-Meters, Pound-Feet, Pound-Inches

[H. L. Chauvin]

Hi Bill,

With us being miles away, many aforementioned suggestions are very thoughtful assumptions without "seeing" exactly what you have; so small added details like in your reply # 10 are important.

In your mentioning, "* The cooling system is down a qt." ......... it would be helpful if we knew since "when".

Also, it would be helpful to report:

A. Overall coolant level and coolant losses after a few days of observing coolant level.

B. ( If coolant were leaking on the floor, appears you would have already checked and reported this.)

C. Is it possible you are having no coolant leaks and not losing coolant when car is parked and not running; however, have noticeable coolant leaks only when car is first
started; and/or have coolant leaks while engine is running.

D. Could be coolant entering a tiny crevice only because of combustion chamber suction when engine is started cold ..... then when exhaust manifold and muffler gets hot ..... coolant makes steam ..... then with additional heat, when engine metal expands with more heat, the leak stops.

[tbirdtbird]

there are some posters here who have forgotten to take their strong prescription medication........
they make Haldol for a reason....
I stand by every word i wrote

[fordfun]

Originally Posted by H. L. Chauvin

Hi Bill,

With us being miles away, many aforementioned suggestions are very thoughtful assumptions without "seeing" exactly what you have; so small added details like in your reply # 10 are important.

In your mentioning, "* The cooling system is down a qt." ......... it would be helpful if we knew since "when".

Also, it would be helpful to report:

A. Overall coolant level and coolant losses after a few days of observing coolant level.

B. ( If coolant were leaking on the floor, appears you would have already checked and reported this.)

C. Is it possible you are having no coolant leaks and not losing coolant when car is parked and not running; however, have noticeable coolant leaks only when car is first
started; and/or have coolant leaks while engine is running.

D. Could be coolant entering a tiny crevice only because of combustion chamber suction when engine is started cold ..... then when exhaust manifold and muffler gets hot ..... coolant makes steam ..... then with additional heat, when engine metal expands with more heat, the leak stops.

HL -

I neglected to mention that my coolant system is essentially "closed". That is, the overflow pipe is connected to a hose that leads to an overflow reservoir so I believe what the radiator spits our is captured. I suspect that I'm losing coolant through another path, and it's emitted thru the tailpipe as steam, as several of you have suggested. I've driven the car 3x this year for a total of about 50 miles.

As previously mentioned, I believe I'm seeing more exhaust (steam?) for longer periods at startup than previously. That is, it's getting worse.

I probably won't get to the compression test until this weekend.

Thanks for all advice - Bill

[Barber31]

Originally Posted by Pete

You are as full of shit as a Christmas goose!
You need a kindergarten course in metalurgy.

I would like to hear your reasoning for this. Although I agree with tbirdtbird I always welcome other ideas that may enlighten me. My 2 points that back up tbirdtbirds comment are 1- "quenching" technique . People who do body work use heat to expand metal and cold water to shrink it back to shape. The same should apply for the studs. 2- I've read the bolt/fastener co. ARP is a top notch manufacturer for this very reason. They are recommended for racing applications for their ability to not stretch like its competitors or snap. So I'd definitely like to hear your ideas on metallurgy that disproves these statements.

[tbirdtbird]

There are proponents of both methods as I already stated. Each camp has its own explanation. Fair enough.
For me, I doubt I will change what I do since in 65 yrs of installing heads, meaning hundreds, I have never had a blown head gasket.

Interestingly, there is a 4-yr college in Kansas where you can get a degree in vintage car restoration. They have some top-notch instructors. All aspects of restoration are covered, mechanicals, body and paint, upholstery, etc. You will have to guess which method they teach there.

As far as ARP bolts, they are superior in quality as you mention, and stretch very very little. When I have used these bolts in some applications I seldom need to re-torque

You will find that the naysayers on this forum will seldom if ever provide any explanations. So much for actually trying to help anyone. They are snipers. Thankfully there are fewer naysayers here than there used to be.

[H. L. Chauvin]

Hi Bill,

Never a bad idea under these coolant loss circumstances to monitor your oil with the dip stick more often ....especially if, as you are noticing ..... coolant loss is increasing ..... coolant in oil is never desirable.

[forever4]

Originally Posted by Barber31

I would like to hear your reasoning for this. Although I agree with tbirdtbird I always welcome other ideas that may enlighten me. My 2 points that back up tbirdtbirds comment are 1- "quenching" technique . People who do body work use heat to expand metal and cold water to shrink it back to shape. The same should apply for the studs. 2- I've read the bolt/fastener co. ARP is a top notch manufacturer for this very reason. They are recommended for racing applications for their ability to not stretch like its competitors or snap. So I'd definitely like to hear your ideas on metallurgy that disproves these statements.

The whole concept of how a bolted joint works and maintains clamp load is based on 'stretch'. Elastic stretch is a good thing. The amount of bolt/stud stretch is controlled through torque application. A non-elastic bolt with "all the stretch removed" is about the worst idea anyone could have for an automotive joint.

The other point is that everything shrinks and expands with temperature change, not just the bolts/studs. Also the head and the block expand and contract. Some 'experts' here don't seem to comprehend that fact.

The idea that premium fasteners are based on "They are recommended for racing applications for their ability to not stretch like its competitors or snap." is also bogus. Does ARP actually say that anywhere?

The sign of a good fastener is both its material properties and design, as well as its consistency and repeatability and minimal variation. Not its ability to 'not stretch'.

In the case of 'low quality' fasteners (think Chinese so-called grade 5 at Lowes), they often have material properties which are lower than their required strength and performance, resulting in permanent yield or fracture during installation or service. Permanent set or fracture is not elastic stretch, and that is a bad thing for fasteners.

Pete is 100% correct.

EDIT:

Originally Posted by tbirdtbird

As far as ARP bolts, they are superior in quality as you mention, and stretch very very little. When I have used these bolts in some applications I seldom need to re-torque

You will find that the naysayers on this forum will seldom if ever provide any explanations. So much for actually trying to help anyone. They are snipers. Thankfully there are fewer naysayers here than there used to be.

No, they actually stretch 'quite a bit', not 'very very little'. That is what makes them work across a range of temperatures and loads.

http://arp-bolts.com/p/technical.php