THIRD BLOWN HEAD GASKET! please HELP!!!!!

[srvtribute]

PHOTO ATTACHED

Here we go.. I assembled, torqued etc. Car ran MINT, 4 times around the block then lost cylinders 3+4 again. I disassembled the head again. Blown gasket in between 3+4 just like the previous time. NOW THE PLOT THICKENS. I compared both blown gaskets and they were identical, with burn marks in the same spot! Now, if you're leaning on the driver side fender and looking at the engine, there is a hole in the engine block at about 1 o'clock in relation to the #4 cylinder which doesn't seem to go anywhere, yet is blocked off by the head gasket. Both times the head gasket had a hole burned through it in that spot. before I reassembled the head, I assumed that this hole was an antifreeze port and there was antifreeze left in the hole before assembly. Could it be possible that the coolant in the hole boiled and blew the gasket?? HELP-

PHOTO ATTACHED

 

[Billm]

Of course you have checked the head and block to see how flat they were before you assembled the engine first didn't you? Is there any evidence of erosion on either surface around the areas of the blow-out?
Bill

 

[Baz]

If there's a warp in there, they'll keep blowing until leveled.

 

[jlaird]

/ubbthreads/images/graemlins/iagree.gif

Has to be something wrong with the mateing surfaces I would think. Check the head first that is the most likely cause. Err, have it checked at machine shop.

 

[srvtribute]

what's your theory on the hole filled with antifreeze?
I'm gonna send in the head tomorrow am. I bought this head reman from victoia b.

 

[Billm]

I just read your links on the MG side and may have changed my mind. If you haven't yet pulled the head you should try TIGHTENING those head nuts to see just where they are NOW (you will need a "bendbeam" type torque wrench to read this) but I will bet that those two (or more) studs are not at 44 ft-lbs but probably at 20 to 30 and either the threads in the block are destroyed and pulling out or the studs are not grade5 but may now be grade "crud" and are stretching and not holding torque.
Bill

 

[Baz]

If it's reman, I would 'assume' that it was straight and level. Is the block warped? If it's your third, then it's not out of the question that some trauma to the block has also occured.
Are you taking the block to the machine shop also?

 

[srvtribute]

Hi Barry,
ASSUME is the key word here. When I first got the car, it overheated at highway speed. I had the original head checked and it was cracked. A mechanic friend of mine installed the reman head. A week later,I lost 3+4 cyl.I then replaced the gasket myself to spec. 10 minuted later I lost 3+4 again I'm assuming the reman head was level. THE CAR NEVER OVERHEATED with the new head.
It's a possibility that it wasn't. I think at this point, I'll replace all studs, nuts etc and get the head checked/leveled and try again. I'm gettin to be a master at dismantling this baby in record time! The good news is that the car ran unbelievable with the new weber dgv. Suggestions/opinions are greatly appreciated!
Eddie /ubbthreads/images/graemlins/driving.gif

 

[jlaird]

What a pain, but you'll get there.

 

[srvtribute]

Thanks for the encouragement Jack! I haven't been this greasy since my Harley shovelhead chopper days. LOVE IT!!!!
Eddie /ubbthreads/images/graemlins/confused.gif

 

[Baz]

It will be a pain, but the midget needs you. There's a not so obvious reason why it keeps a' poppin, that you'll need to track it down so it doesn't keep happening. Nothing more frustrating than to keep repairing something, and it go bad again. Take your time.

 

[srvtribute]

Im there for the little devil ,which I've affectionately named "TAZ". I will not rest until it's solved!

 

[Morris]

Where are you sourcing those head gaskets? The 77 1500 should have a recess around each cylinder bore and a ring on the head gasket that fits into said bore to prevent it from blowing between cylinders. The gasket in the picture does not appear to have the ring. Earlier Triumph 1500s and 1300s (essentially the same engine with a different crankshaft) did not have this ring. Is it possible you are using a head gasket for the early engines?

 

[srvtribute]

Good eye! That pic was for reference purposes. The 2 I used, from vb and one from an import shop. They both had the ring on the gaskets. The 1/3 inch bores in the block still have me puzzled. any info on those?

 

[Morris]

That's what the ring fits into.

I reccomend only using Payen brand gaskets. I also reccomend buying them from Tony (theautoist.com I believe).

If you previously had a cracked head, things must have gotten pretty hot at some point. It may be neccessary to mill the block which could have gotten warped a bit when the head cracked?

When is the last time you check your spark timing? Could spark detonation cause this problem? It doesn't seem like it. Maybe someone smarter than me knows...

 

[DrEntropy]

Remove all the studs and check the block (after scrupulously cleaning it!) for raised metal around the stud holes (chamfering these is a real benefit, BTW) and the block surface with a GOOD straight-edge. Should not be able to see light twixt block and tool anywhere... I think the most "gap" permissible is 0.002". Good to have a shop check that "reman" head. Take nothing for granted at this point.

On reassembly, clean the stud holes "hospital clean" and use red LocTite on the stud-to-block threads. I *DO* lube the nuts (some will cringe and take exception) on torquing the head in place, following the "map" for sequence. And I've rarely "retorqued" cast iron to cast iron head/block LBC's. Though in this instance I would be inclined to do it.

HTH!

 

[jlaird]

Excellent advise Doc. I completely concur.

Thats a big 10-4

 

[DrEntropy]

Can we get a fee for the consultation, Jack? /ubbthreads/images/graemlins/jester.gif

 

[jlaird]

Yea prob Doc. That good feeling you get when you help out even if it is via long distance.

 

[DrEntropy]

/ubbthreads/images/graemlins/thumbsup.gif Works fer me.