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Blown head gasket..

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ronzet

ronzet

Jedi Knight
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LBC Fans,

After fighting my cooling problems I have finally determined where my coolant was going... out the tailpipe...

I have pulled the newly rebuilt and milled head an have ordered a new head gasket..

I have a question however.

I had installed and spec torqued the head and have run it for probably 300 miles... I, hate say this, failed to retorque the head a second time.

The query.. Is it necessary to have the head remilled in case of any warpage or should I just re-install and torque.. run for a little while and retorque???
 
If the 'decked' it 300 miles ago & it was flat & you've not run it hot, it shouldn't need anything done to it....I'd be more interested in why a new head gasket went in 300 miles!
 
Tony,

I DID overheat it once... to a point where it quit....cooled down and then drove it home. It was at night and since I have yet to put panel lights on the gauges did not see the temp gauge until it was well into the 230+ range... I did a compression check afterwards and found that 1,2 and 4 are 165 psi, 3 is 150.. about what it was right after the re-build.

When I pulled the head there was a few water beads in #1 only. I could not determine from the gasket where the leak was...
 
Straightedge the head, Ron. With a MACHINIST'S straightedge. That'll tell the tale.
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif since you ran it hot.
 
Tony and Dr.Entropy,

As usual, a wealth of knowledge at our beckon call... /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif

Will advise results of straightedge test... I will shine a light behind the straightedge as I check the surface... /bcforum/images/%%GRAEMLIN_URL%%/rolleyes.gif
 
With the straight edge, use feeler gauges to check for gaps, make sure you apply pressure at the staright edge at the point you are checking, a head gasket will handle up to about .002" gap, after that is needs to be decked.
 
Hap Waldrop said:
With the straight efge, use feeler gauges to check for gaps, make sure you apply pressure at the staright edge at the point you are checking, a head gasket will handle up to about .002" gap, after that is needs to be decked.
Click to expand...
That, folks, is information that needs to be printed & put in your garage notebook!
 
tony barnhill said:
If the 'decked' it 300 miles ago & it was flat & you've not run it hot, it shouldn't need anything done to it....I'd be more interested in why a new head gasket went in 300 miles!
Click to expand...

My Spitfire did the same thing. I've determined that I should have invested in new head studs and not tried to re-use the originals.
 
Hap,

Thanks for the guidence....... This process will be done this evening and I will let you know what I find.... /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
Just a quick update....

I had my radiator re-cored, bought a fan shroud and installed them this weekend... Unfortunately I had set the rocker cover inside next to the grille , installed the radiator only to find that I could not get the Rocker Cover out past the radiator soooo, uninstalled and reinstalled the radiator and shroud )(#)@#*($)@#$*)

Then, after checking for the .002 or less clearance on the head and block (in case it had warped)... installed the head and torqued it.. 25, 40, 50 ft.lbs. three times around... # 10 BROKE on the third round..... sigh... ordered a new set of studs....

<span style="font-weight: bold">BY THE WAY... The head gasket is new... CAN I re-use it even though it has been torqued but not run??? Please advise..</span>
The good news is I got my B running and back on the road... I worked on it because I did not want to break SOMETHING ELSE on my A on Sunday... AAARRRRGGGGHHHHH :wall:

I will let you all know how the radiator and shroud works once I get the D***d car back on the road....
 
Go get a spray-can of "HighTack" Permatex. Wipe the "pre-torqued" gasket clean and follow the instructions onna can after ya have those shiny-new head studs-n-nuts.

ummm... and ya may wanna invest in a "tea cart" for layin' out parts on, from now on. :devilgrin:
 
DrEntropy...

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]ummm... and ya may wanna invest in a "tea cart" for layin' out parts on, from now on.
[/QUOTE]

Nawww, I just keep throwing the parts over my shoulder as I remove 'um... :square: OR burying them in some obscure inaccessable spot.... :thumbsup:
 
Update:

I received the replacement studs yesterday and installed them along with a new head gasket and new rocker studs and the necessary miscellaneous gaskets... I worked into the night and at about 12:30a, finished putting everything back together...

I turned on the key, heard the familiar ticking of the fuel pump, but not enough juice to turn the car over... :wall:

I will charge the batteries this afternoon and start it all up...<span style="font-style: italic">film at 11:00</span>

<span style="font-weight: bold">By the way, how long before I re-torque the head???</span>

ALSO.. by the way.. what happened to the large selection of comic heads?!!??

Thanks..
 
Oh, 100 miles or so, several good cycles of hot to cold on the engine. I seem to remember the dealers recommended 1000 miles.
 
Thanks for the advice Jack.... I just want to DRIVE the D#)$ thing without worrying more than is usually needed....
 
If ya HighTack'd it, you might even FORGET the re-torque. If ya just *need* to feel like you're useful, do it at a third full "heat/cool" cycle.
 
DrEntropy,

Thanks for the comment and advice...

I used a new gasket but opted out of the high tack treatment.. not that it was not good advice, I have a bias against using gasket seals or treatments in areas like the head, exhaust, etc...

Call me crazy, :crazyeyes: but scraping old gaskets off when replacing with new is not one of my favorite pastimes....

For future reference, however, I am always willing to learn new things, sooo the high tack product is one that grabs but will easily release when being removed???

Thanks again
 
I'd recommend the retorque even with the high tack, you find the outer studs will take more turning on the retorque than you would imaging, yes on the high tack being easier to clean up on than composite gasket alone.
 
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