Cracked head

Ja564rm80

Ja564rm80

New member
Joined
Sep 9, 2013
Messages
107
I have a 24v head that has all the bells and whistles. Pulled it off mid season to put rings in the truck and noticed the head has a few cracks in it between some of the valve seats. Doesn't leak or show any signs of anything going through them. I have talked to a few shops and they all say its garbage. Seat will fall out. But I have also talked to some pullers who say where it is cracked is normal. So I guess I'm not sure what to do now. New head? Or just a valve job and run it as long as I can?
 
I've wondered the same thing. Not too big of a deal on a stock head, but when you have a lot of money in one, what's the best way to go. I know they can press in over sized seats and "ping" the head to prevent coming out.
 
The head on my dually was all spider webbed. None of the cracks went through the seats tho. Ran it for quite awhile under some heavier boost (85lbs or so) for awhile.

I was told the same as y'all. But I went through 3 different heater cores in this truck, and can't help but wonder if under heavier boost if those cracks expanded and maybe let some pressure into the coolant system?

Other than that, it seemed to run fine. But being kind of bit picky, I'm going to be replacing the head for price of mind..
 
Every head will crack new or used. If its not cracked yet it will be soon. The one on my 3.0 truck was cracked before I had it worked. Its run fine. It kind of depends on how bad and where they are. On a 12v I wont run one that's cracked to the injector hole but I have used them cracked between the valves. Some times what you are seeing in the seat is just surface cracks and after a valve job the crack goes away. Post up some picks
 
The valve seat does not appear to be cracked. Just in between the od of 2 of the seats. I will try to get some pics up later today!
 
When we pulled our 12 valve head after our turbo explosion, I had to pull the valves to clean the aluminum from them.

Every exhaust seat was cracked through the seat and into the head. Some had several cracks and some were cracked between the valves.

I simply had no other choice so I lapped the valves back in and ran the head. It is fine so far.

None of the intake seats were cracked.
 
Ja564rm80 said:
The valve seat does not appear to be cracked. Just in between the od of 2 of the seats. I will try to get some pics up later today!
Click to expand...

What that is a hot spot. Some have milled that little ridge down so it doesn't get hot and crack. Are you sure it has press in seats? Some 24v didn't. I believe in 01 they went to the press in seats as my 01 dropped one but I have a 2000 head that doesn't have them
 
DISTURBED said:
Every head will crack new or used. If its not cracked yet it will be soon. The one on my 3.0 truck was cracked before I had it worked. Its run fine. It kind of depends on how bad and where they are. On a 12v I wont run one that's cracked to the injector hole but I have used them cracked between the valves. Some times what you are seeing in the seat is just surface cracks and after a valve job the crack goes away. Post up some picks
Click to expand...

Why wouldn't you run one that's cracked into a injector hole?
 
6.4 F-350 said:
Why wouldn't you run one that's cracked into a injector hole?
Click to expand...

I don't like to run them because the only thing stopping the compression/fire from blowing back up past the injector is the copper washer. I just wont run them on a high hp build with all the money spent in machine work. I had one do that and it ate the injector washer till I figured out what the issue was. It mostly falls back to how bad they are cracked. I did have a head crack between the valves so bad you could almost stick a #2 pencil lead in it. I was blowing between the intake and exhaust port on my puller.
 
Last edited:
The head on my drag truck was cracked when I ported it and mounted the intake on it 6 years ago. At the time I did it it was just kind of an expiremental thing and I thought if it didn't work out it was a cracked head and I wouldn't have much to lose. Last spring I built a new 6.7 motor and I put it on that. I am making somewhere in the 1400 hp range . There are more cracks in it now then 6 yrs ago but its not leaking the seats are tight and its making good power.
I would check and make sure the seats are still good and tight and if they are I would run it.
 
thank you toolman!!! that was kind of what i was looking for. i hope it lasts!!
 
You must log in or register to reply here.
Back
Top