1dirtyZ

iTrader: (1)

i had just finished putting in the thicker cometic gasket and head studs. i then went to the track to see what i could get. the funny thing is it never pulled as hard as it did before, but i thought it was because of the lower timing.
any how, i do my first run and the car wasn't pulling as strong.
then half way through the secont run i started hearing a tapping noise, i thought it was the clutch comming apart cause it was slipping during shifts, but then it got lowder and i let off. all i could hear next was something like a bad bad exaust leak and there was fluid leaking underneath. so i drove the car back home ( about a mile) with a slight miss and low power.

now to the damage part, i took the heads off and the driver side head had a hloe where it mates to the gasket at the #7 piston. it fried the gasket too. at this point i don't know what went first , the gasket or the head. but i know this: the head has a gouge about 1/8 inch deep.

the other weird thing is i have forged pistons, and they all had a brown tint to them before, after i took the heads off, there was slightly less tint, but at #7 the piston was chrome like new? what caused that? lean condition, the hole and water seepage?

MelloYellow

What year heads do you have?
Not the 97-98 year with the hole notch that allows MLS gaskets to seep/leak, right?

1dirtyZ

iTrader: (1)

no they're the newer ones , 2000-2001 heads.
and trust me the leak is from a hole that seems like something shot right through the head!

MelloYellow

Crazy!

Ported or stock heads?
6.0L heads?

Weld repair work?
How are the springs on Cyl #7?

y2khawk

iTrader: (5)

the clean piston is most likey due to the "steam cleaned" effect of water in the chamber.

Too thin a port job hit the water jacket in the head??

30thta436

iTrader: (10)

How about some pics?

SJH

been there done that years ago with blown 5.0's.
You went lean or detonated, then the headgasket blows, then the combustion goes to work like a cutting torch and notches the heads.
Did that to a new TFS high port head.Had it welded and it was good as new.
You should be able to get it welded up and repaired.
Another time something similar happened but this time we flame notched the block deck and bores. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
No fixing that.
20+psi back in those days when we were still learning = lot's of $ for broken parts.
Good luck with the repairs.
Steve

1dirtyZ

iTrader: (1)

the springs were brand new, i just put them in.
the heads were 6.0 that were ported, but the water came from the hole that was punched out.

and i belive the steam cleanning effect was the cause for that clean piston.

now when you said flame notch what does that mean? is it when the combustion gases escape and cut the head?( isn't that the same as blowing a gaket and having a leak?)

i don't think it went lean , cause the other pistons were ok, and i'm leaning towards the theory that says the head studs didn't clamp down well enough on the gasket. i guess i'll try and repair the head and use the oringed gaskets again.

i'll post pics as soon as i get them.

SS00Blue

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by MelloYellow:
<strong>Most likely the port work got a little thin on the heads.

Did you get them from ValveGod?
Sometimes he sells repaired/re-welded chamber heads that have failed on occasion.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'll call Sean on this post, for sure. I KNOW he'll want to respond. I've dealt with Sean for a few years, and there are others in my business that have dealt with him. His rep is flawless as far as I know...

SC-

PS- I'll go with Matt on this one. Most likely a severely thin port job, weeping into the cylinder. I know of some AFR heads that are famous for this.

<small>[ November 24, 2002, 02:29 PM: Message edited by: SS00Blue ]</small>

y2khawk

iTrader: (5)

Where is the hole exactly?? In the chamber? Did you have the heads machined for bigger springs?

The 6.0 heads I got from Shawn were welded in between the chambers on both heads. At least one spot on each head.

I've had zero problems with them, studs used. If they are torqued to spec you shouldn't have a problem.

1dirtyZ

iTrader: (1)

i belive my heads were also welded between the chambers, but thats not where the problem is.
the leak happened at the point closest to the outside of the chamber (towards the header side), where the gasket is thinest (?).
or you could say halfway between two of the lower head bolts.

i'll try and get pics as soon as i can.

by torquing the studs to spec , do you mean the actual studs in the block or the nuts on the studs?

<small>[ November 24, 2002, 03:28 PM: Message edited by: 1dirtyZ ]</small>

SJH

ho hum..heck maybe it was a bad head.
But like I said , combustion gas notched head decks and blocks are nothing new.
I could tell a lot more though from a pic of the damage.

MelloYellow

I don't mean to jump the gun. Just thinking of what I've seen over the years. Was more port work done after the 6.0L heads arrived?

1dirtyZ

iTrader: (1)

the only work on the ports was touch up work, i checked the ports and they were ok, but i do agree with you mellow, i heard my fare share of port work going bad.

i'll have the pics tonight.( i hope <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> )

1dirtyZ

iTrader: (1)

i have the pics but don't know how to post them.... <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
can someone help me out??

MelloYellow

You could email them to me Zipped and I could post them on Yahoo. Yahoo shrinks them down a bit tho.

1dirtyZ

iTrader: (1)

thanks mello,i think they are about 600k for both , i'll try and email them now.

MelloYellow

Heya,

Here you are:

http://photos.yahoo.com/bc/mjarnoldphotos/vwp?.dir=/Head+%26+Gasket&.src=ph &.dnm=hole+in+head+1.jpg

http://photos.yahoo.com/bc/mjarnoldphotos/vwp?.dir=/Head+%26+Gasket&.dnm=hole+in+hea d3.jpg

Looks like a blown headgasket and really bad detonation, but I'll let the experts speak to it. Doesn't look like a head failure to me.

I've only heard of 1 of the re-welded 6.0L heads ever having a problem in the past. Not sure why the welding is done or if it can cause any strength/structural issues or why some of the 6.0L come that way. Doesn't look like your issue tho.

What bore gasket did you use from Cometic for the 6.0L head bore?

<small>[ November 24, 2002, 10:00 PM: Message edited by: MelloYellow ]</small>

1dirtyZ

iTrader: (1)

thanks alot mello, the gaskets i used were 4.060 and i have a bore of 4.030. the difference is because that slight gap ( about the thickness of 3 papers ) helps keep the gasket edge away fron the combustion chamber which helps reduce the chance of detonation when the head or gasket shifts.
i belive lingenfelter and mallet use that trick.
the wierd thing is i didn't hear any detonation and my timing was set at 20deg.

what if the head wasn't sealed well to the head ( stud not tight enough?), would that cause this kind of damage?

MelloYellow

I'd like to hear other replies for sure.
How about which spark plug type? Gap? Clogged injector? Why is it always Cyl #7 that goes out?

SJH's comment "combustion gas notched head decks and blocks" sounds accurate. This is the first time I've seen this gas notching tho. Makes sense.

<small>[ November 24, 2002, 10:16 PM: Message edited by: MelloYellow ]</small>