Flathead 6 head gasket issue?

[Guest 251flathead]

Hello everyone, this is my first post. I recently purchased a 1950 Chrysler Windsor with a 251 Flathead 6 with the Spitfire head. It has 88,000 original miles. Cylinders 1,2,4,5, and 6 all have 110 psi compression, while #3 has 100 (not too bad) and the oil pressure is at 55 psi while cruising. The car runs really well, but I've noticed lots of steam from the pipe even after it's warm. It seems like it often wants to steam. I can take it for a nice, long drive, park it for 30 minutes, and have it steam and drip a puddle of water under the tail pipe. Maybe this is normal, but none of my other cars have ever done this. They steam in the morning until everything gets hot, then the steaming stops.

The oil isn't milky, so I'm not sure what to think. The coolant looks ok. The steam isn't sweet smelling, as far as I can tell.

I'm asking because even though my gut tells me that maybe it's normal for an old car (my first classic), I'm still afraid that there could be something wrong. Does anyone have any ideas? Should I just do it anyway and use the opportunity to clean out coolant passages and the combustion chambers? I would just go ahead and do it, as it's an easy job, but I hate to tear into a good motor for nothing. #3 being the only cylinder with a variation makes me curious upon this...

I really appreciate the help everyone,

Dan

[Rusty_OToole]

It does sound like a failing head gasket.

Here is a simple test. Take out the spark plugs and examine them. If any plug is perfectly clean it indicates a coolant leak into that cylinder.

What does your heat gauge say ?

It is possible to pressure test your cooling system with a pump that goes in place of the rad cap. Any garage should be able to do this.

Your car does not have a coolant overflow container. So, you need to leave room for expansion at the top of the rad and not fill it completely full. As long as the top of the rad core is covered when cold you are OK.

These are the first things that come to mind. I would check the spark plugs before I did anything else.

Edited February 16, 2011 by Rusty_OToole (see edit history)

[c49er]

Be careful pressurizing these old MoPar radiators-the chrysler was maxed out at 4 lbs pressure. You get it tested at too high a pressure and you will find a leak- a new one!

Bob

[JACK M]

A leak down tester that goes into the spark plug hole may help you. Put several lbs into the cylinder and look for bubbles in the radiator, or water from the exhaust. The plug from that cylinder may look cleaner than the rest as described above.

[Guest 251flathead]

Hey everyone, thanks for the replies. I actually just replaced the plugs a couple hundred miles ago or so and they all looked normal. The car was stored since 1969, so I figured a tune up was in order . I could recheck them, which is not a problem.

The car use to run in the 165ish range, but now runs in the 195 range after I drained the coolant and put in a fresh 50/50 mix. I didn't flush it (didn't have time), which is what im doing next week. Im also going to pull the freeze plugs and clean out any sludge I find. Im thinking that when I fooled with it I stirred up some stuff and now it for sure needs a flush.

So, im not sure if it needs it, but if I do the cooling system, id like to do the hg if needed.

[Joe Cocuzza]

to all in this Forum.

I have copied and pasted a thread from the Buick Forum about using the "new" type anti-freeze in our older cars.

Here it is:

Under NO CIRCUMSTANCES should an "Extended Life" antifreeze, which utilizes Organic Additive Technology (OAT, H-OAT, or N-OAT) as one of its chemicals, ever be used in our cars over 10 years old. It attacks the gaskets and gasket cements in our cars, causing major leaks and forcing ultra-expensive repairs. The "Silver Ghost Association" Rolls Royce people have documented massive cooling system failures apparently caused by this anti-freeze product.

Antifreeze that can be used safely in our cars uses older-fashioned Inorganic Additive Technology (IAT) additive.

You cannot tell by the color of the antifreeze if it's safe to use. Also, the product may be labelled "Safe for Older Cars"--meaning 10 years old at most. Brands to be AVOIDED are all Prestone lines and Zerex's G-05 in the Gold-color container. Avoid any "extended-life" antifreeze. None of us wants to pull and rebuild our cars' engines.

Acceptable brands are Peak, Peak's HD Product "Sierra," and Zerex Original Green in the WHITE container.

If any of the OAT, H-OAT, or N-OAT products are in your car the cooling system should promptly be drained--radiator and block-- the system flushed thoroughly, and IAT antifreeze installed. I am checking to see what's in my 37 Buick and 40 LaSalle.

The article is in Newsletter LVII Number 8 2010. It will be posted on the ACDCLUB.ORG site in a few days in the newsletters section of the forum.

Forewarned is forearmed.

[Alfa]

All the above is excellent advice.

Given that you have good compression pressures in all but one cylinder, and that the low one is still with 10% of the others, I would not worry too much about loss of compression.

A cylinder leakage test would be an excellent idea as this allows for diagnosis in that you can hear where the air is escaping.

One final thought; does the car have a stainless exhaust? Stainless steel is a very poor heat conductor and tends to cause more steam at the tailpipe, and for longer, because the exhaust gases remain warm until they reach the tailpipe exit. It may be nothing more serious than this.

Adam..