Recovering from Blown Head Gasket?

[The Eclector]

I have a '30 Model A Speedster running a Thomas high compression head. Last week I blew the head gasket. Fortunately I was about a half a block from home and was able to shut down the car shortly after it happened. I have since drained both the coolant and the oil. There is evidence of coolant in the oil and perhaps some hydrocarbons in the coolant as well. BTW, coolant is conventional green 50/50 mix.

Q: Is there anything I should do to ensure that I've removed all the coolant from the oil? Once everything is back together and I've put in new fluids, I plan to do at least one oil change after I've driven for a few miles. Should that be sufficient as long as I'm not seeing more coolant draining from the oil sump? Any other suggestions?

Q: Regarding the coolant, is there any reason to do flushing beyond just draining the fluid?

BTW: I suspect the cause of the gasket failure is due to some work done recently on the upper coolant connection tube at the head. The nuts were removed to resolve a leak and reinstalled but never properly torqued. Things were fine but the gasket blew when stomping on the pedal when going about 30 mph. The water pump gasket failed too and coolant was pulsing out of the water pump housing flange with each engine stroke. It was rather dramatic. The head and the block surfaces both look good.

Thanks!

[denniskliesen]

Drop the pan and clean it. That is a must IMHO.

[H. L. Chauvin]

Hi Steve,

In your first question, " Any other suggestions?"

Believe it or not .... there are always one (1) or more reasons why head gaskets fail.

Just to guess at a few: (A) Head and/or block not dead "flat". (B) Studs not tightened in order recommended at proper torque. (C) Incorrect head gasket ..... and the list stretches out towards infinity.

If you know why it blew, we will not need 763 thousand guesses as to why it blew.

[mike657894]

there is about a half a quart or more that gets trapped in the pan.

[MikeK]

Dennis mentioned dropping the pan. Very prudent, as coolant may have filled the oil dipper trays and will not be removed by a simple oil drain.

There is another way to empty the dipper trays without dropping the pan, but it is not for the everyday garage mechanic. It depends on what equipment you have. If you tilt the entire vehicle 38 degrees to the left (carburetor side of vehicle raised up) the dipper tray will empty all four valleys completely into the pan. The fuel tank needs to be less than half full and both left wheels temporarily replaced with old rollers and securely blocked well above the rim line.

[The Eclector]

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Originally Posted by H. L. Chauvin

Hi Steve,

In your first question, " Any other suggestions?"

Believe it or not .... there are always one (1) or more reasons why head gaskets fail.

Just to guess at a few: (A) Head and/or block not dead "flat". (B) Studs not tightened in order recommended at proper torque. (C) Incorrect head gasket ..... and the list stretches out towards infinity.

If you know why it blew, we will not need 763 thousand guesses as to why it blew.

I edited the original post to include my assessment of why it failed. Please re-visit the original post for details. Thanks for the suggestion.

[H. L. Chauvin]

Hi Steve,

Many have had one or both of the ears on this water outlet break when torqued at or above 55 ft. lbs.; hence, some are reluctant to properly torque same.

Never a bad idea to check flatness of both cast iron joint faces where this water outlet abuts the head.

Chances of ear breakage are lessened considerably when omitting this standard thick gasket and substituting a thin, had made manila folder gasket with Permatex No. 2 non-hardening sealant applied to both sides.

With Model A's, appears one may never know until he tries.

[larrys40]

In addition to pulling the pan I would pull the valve cover as well. Oil gets pumped up to the valve chamber quickly and many times upon a breach the valve chamber gets very milky and then lays there. Lots of shop towels to clean it out

Larry shepard

[Ernie Vitucci]

Sometimes we forget to re-torque the head once a year. When I do it, and I drive the car quite a bit, one or two nuts will move a bit. Ernie

[Hotrodfil]

The gasket failed under my Thomas head a few weeks ago. Turns out the 'hardened' washers I'd bought were in fact made of some kind of cheese I reckon. The new nuts I'd used were little better. Suffice to say the nuts were not particularly tight.

[29er]

Originally Posted by Hotrodfil

The gasket failed under my Thomas head a few weeks ago. Turns out the 'hardened' washers I'd bought were in fact made of some kind of cheese I reckon. The new nuts I'd used were little better. Suffice to say the nuts were not particularly tight.

You put washers between the head and the stud nuts?

[Tom Wesenberg]

Originally Posted by 29er

You put washers between the head and the stud nuts?

That's recommended for aluminum heads.

[WHN]

Originally Posted by Ernie Vitucci

Sometimes we forget to re-torque the head once a year. When I do it, and I drive the car quite a bit, one or two nuts will move a bit. Ernie

Thank you for this advice. I just checked, had 4 nuts that moved 2 or 3 lbs. and one needed 6 more lbs.