Blown head gasket. Removed head today.
 

Head gasket has slightly over 1000 miles on it however it is a gasket out of an ebay gasket set.

Head bolts have over 195k on them.

Those are the only reasons I think of. Im 99% sure there wasn't ever any detanation. The car wasn't over heating. Cylinder #2 is the only one I can see water in, the others look dry. Here's a pic of the plugs.

1,2,3,4
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double check the torque on the head bolts. my brand new gasket blew within 25 miles. my torque wrench was waaay off calirbration, like 20 lbs less. put my bolts at 40 lbs.

http://boostedmiata.com/blown_engine/headgasket.jpg

Who built the motor? whatmiata?

Did you put a straightedge on that head and made sure it was in specs?

Yes he did and yes he did.
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99.9% of the time, the reason for a blown head gasket is a warped mating surface...either on the block or head.

He probably fucked something up. My guess. Or you detonated. Pull the head and find out what's wrong. Check the torque on ALL the head bolts before removing it for reference. If it detonated, it will almost always blow between two cylinders. I can not stress this enough, yet you will likely ignore it: DO A LEAKDOWN TEST! There, I said it. Do this and all will be known.

Correct me if im wrong, but I have to replave the gasket in order to do the test, right? Otherwise it will deffinately give false readings, right?
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The test will tell you % cylinder leakdown. If it's blown a head gasket, it will probably leak a lot. :) But doing a leak down test before tearing it down will give you insight as to the actual problem, and what caused it. IE- you may find that pressurizing cylinder 2 results in air pouring out of cylinder three, showing that you blew the HG between two cylinders, hence detonation probably caused the problem. It also might show a trace amount of leakage between 1&2. You may pressurize cylinder 2 and find air leaking into the cooling system as evident by the air bubbles coming out of the radiator. Probably a warped head or deck, improperly torqued head, bad bolts, etc. Or you may pressurize cylinder 2 and find excessive blow by, indicating a cracked ring landing or something of that effect. If it leaks past the rings AND leaked into cylinder 3, you likely had detonation. Where if it only leaked into the crankcase but the HG was fine and no other leaks appear, it's probably from poor machining. (read, honing only instead of bore and hone)

Point is, you'll know exactly what's wrong if you do a leakdown. Don't worry though, like I said, you'll probably ignore this advise and just yank the head off and try to guess what was wrong, fix what you think is wrong, and roll the dice again and see if it fixes it. Check out NA6C-guy, he did this four times in a row. :giggle:

Thanks Pat, The gasket is deffinately shot. #2 cylinder has a puddle of water sitting in it while the other 3 are dry. Also with the car running and the rad cap off the water jumps like crazy.
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wow pats take it easy.... how could you just come on thread and say i "f" up. with out even taking it apart and inspecting your self... you got something against me or something? Ive built plenty of engines and never blew a head gasket. I have a fresh snap-on torque wrench that the engine was assemble with. If the wrench was off i think the engine would have let go and my engine also... phil the thread start/owner brought me the head and said it was fine and did not want me to take it to the machine shop to check it.. so i copper spayed the head gasket put it on and torque down the head to spec, with the original bolts when it said in the factory manual they should be replaced. so who knows the head condition, and what those bolts have been stretch to. also phil did have issue's with water temps (seeing 220+) when he got the engine in. so take it easy with all the putting the blame on the builder.

:fawk:

Yes I did, and whats worse is it was never the damn head gasket in the first place. I was ignoring logic because I thought I knew better (than logic, go figure). The first time it was because of a staple sandwiched between head gasket layers (but the 1.6 isnt MLS is it? So no worries there), but apparently after that, it was my oil control rings, and what I thought was oily coolant, was just oil... stupid me for assuming. I have no advice though, Im probably the last one needing to give advice. Like said, it only took me 4 extra head gaskets, and 4 months of work to get it running (after a full bottom end rebuild of course). :giggle:

You've said some things in the past that showed you weren't much of a machinist/engine builder.

If you didn't check the head, then you don't know if it's warped. No way in hell an engine builder bolts a head down without checking the deck first. It takes a minute of your time and cost nothing. That's ludicrous that you didn't check it. Who checked the deck for flatness? Who checked the head for cracks? Did you chase the threads and degrease the bolts and threads before torquing the head?

If the bolts have been used more than 2 or 3 times before, I would have replaced them. I recently torqued mine for the 3rd time and one reached its yield point stress on the last round of torquing. I stopped before I broke it obviously, but the next time they come out, it's getting new bolts.

Also, did you retorque the head after 500 miles? With a composite gasket you have to, especially for a boosted engine (which should have got a MLS gasket in the first place, hint hint).

So far we have:

• A head that may be warped
• Possibly a cracked head
• A deck that may be wapred
• Head bolts that may be bad
• Head may not have been re-torqued after 500 miles

Sorry, but whatmiata guy ain't building any of my motors. I'd have no confidence in my engine if it lost a head gasket due to one of the above problems. I hope this is the last major issue you have.

CAN I BUILD YOUR NEXT ONE!? :hustler:

lol ok you know what pats......... im sorry you know what your taking about and i dont. maybe you should be a engine builder.. you prob be the best in the world. hey apply for a job in a shop or maybe a high performance shop even. because your the best and right and sorry that i questioned your knowledge.

I've not heard this one...perhaps this is why i'm losing so much oil on my new motor...

Hell, I retorqued my MLS 3 times before I ever started the engine and still had the nuts on the ARP studs tighten up a tiny ammount each time (a few days apart each time). A composite for sure HAS to be retorqued, its not just a good thing to do, its a must.

Very easy to do on a miata, i'm going to check this out tomorrow. I'm sure I need a re-torque. I wonder why FM didn't include this in their instructions they include with the ARP studs...?

When I rebuilt the top end of our integra I also didn't re-torque. It'd be very difficult since you have to remove the cams...

Not related...look elsewhere

I also think you are supposed to do it cold, since the aluminum head would expand when hot. Maybe that is common sense though.

Im not really sure as to why mine didnt hold torque. I may also check mine this weekend. New rebuild at ~350 miles.