Guess the issue!?

[HOOV3R]

electrolysis? Isn't that like a hair removal procedure?

WTF? LOL

 

[Denver]

I bet something like a small nut or bolt made it's way into the cylinder and destroyed that hole or a bent rod.

 

[Derek@Vision Diesel]

Well the head is off.

We have clear valve to piston contact on a couple of cylidners, though very faint on most. #5 has a pretty good knick in it, not sure what could have caused it other than installation error or something. No cracks that I can find and without removing valves everything looks good so far. Other than the fact that the piston is coated and its very clear it wasnt burning very hot in there.
#3 and #5 have the best indication of some piston/valve romance, but it doesnt look like anything i havent seen before.

Going to remove valves and see what we can find.

Also going to get the fan out of the way so we can roll the motor over, that piston was at TDC when i pulled the head off so i cant see the cylinder wall at all.

 

[Derek@Vision Diesel]

Piston #5:

Piston #1

 

[Twisted Excursion]

Guessing got a lifter that came apart.

 

[FORD7.3]

Called it..

 

[SteveBricks]

^^^^^Caused by too much material removed from the heads.

 

[FORD7.3]

^^^^^Caused by too much material removed from the heads.

Exactly!!

 

[Derek@Vision Diesel]

Question for you guys, havent been in the business long enough to know the specs.

at what point do you get to "too much" on taking material off the deck? .012-.014 was removed here.
The valves and rockers all operated great before removal of the head, ill inspect lifters here in a few minutes. Really thought I would find something more obvious though.

 

[hawgdoctor]

Our machinist won't go over 0.010" on 6.0, or 6.4 heads. After that you are wag under the minimum thickness FWIW.

Sent from my DROID RAZR using Tapatalk 2

 

[Derek@Vision Diesel]

Our machinist won't go over 0.010" on 6.0, or 6.4 heads. After that you are wag under the minimum thickness FWIW.

Sent from my DROID RAZR using Tapatalk 2

Good to know! Well more than that was taken off here, as ive stated.

Lifters all seem to be in tact.

 

[brian89]

Not a machinist but i feel that if somebody gives me a range for amount of material removed, they don't know what they are doing, a range beforehand is different, but after i feel like it should be one number, .010" removed. just a thought

 

[Derek@Vision Diesel]

Not a machinist but i feel that if somebody gives me a range for amount of material removed, they don't know what they are doing, a range beforehand is different, but after i feel like it should be one number, .010" removed. just a thought

If it is warped then there is different amounts removed in different areas.

 

[Mdub707]

There's no magic number for what can our can't be removed. Fords spec is a minimum head thickness of 3.74in. IIRC

 

[brian89]

Ahh i see, makes sense, my bad

 

[Mike's Diesel Performance]

I won't go over .008" at the very most.

 

[kevin]

im a newb when comes to these 6.0s But to me that block looks like its been decked.. doesnt look like anythings been shaved off the pistons

 

[Derek@Vision Diesel]

Let me ask you this.... Not a motor builder here (yet), but what is the amount that the piston should go above block surface (if that makes sense?). Is that amount measurable?

I believe the block has been decked as well or just cleaned extremely well.

Being as though these heads have over .012 taken off of them, would the consensus be that they are junk and we should start fresh? I havent done enough of them to recommend forking out the money for new heads... We do appreciate the help though, love to learn!

 

[Derek@Vision Diesel]

some things come to mind... if for some reason too much was taken off the head, what issues start happening. Protrusion was set accordingly so it shouldnt be valve interference or anything. The heads get weak, i realize that, but these havent failed in any way yet, no cracks or anything.

 

[kevin]

i dont remember the piston
protrusion off the top of my head.. if they took X much off the deck Then they should have taken X much off the pistons