6.0 headgaskets leaking with ARP studs
Let me start off by saying long time reader, first time poster.
I have an '03 F350 6.0L and I have been head studded for over 3 years and 160,000+ km. The work was done by myself and another tech while we both worked at a local Ford dealer. I had pulled the engine and did a complete re-seal at approximately 205,000km. The truck now has 360,000km and I have since moved on to another shop and no longer work for Ford. l also have egr blocked off and have been running a Diablo Predator tuner since studs. Nothing much else done other than AFE intake and MBRP exhaust.
Started with noticing lack of heat on decel when coming to a stop and then also some venting/wetness around my degas bottle cap. I tried a new cap and thermostat to start and that didnt fix it. Next I installed a pressure gauge inline with the degas bottle and this is where Im pretty sure my heads/gaskets are leaking again. I have 17psi with the cap on after a hard road test (which anything more is getting vented via the 16psi cap) and it goes from 0-15psi in less than 5 min of mild (light acceleration, less than 10-15psi boost) driving when its cold. I never left the gauge on the resevoir any longer to see what the max it went to because I didnt want to over pressure the cooling system and rupture a hose, etc.
We used a combustion sniffer in the degas bottle but our fluid was a couple years old (not sure if it has a shelf life or not) and the fluid didnt change color as I expected it to with the cooling system pressure up so quickly with what I am pretty sure is combustion gases. I have been talking back and forth with one of my Ford diesel tech friends and he is pretty sure its my heads leaking again. Just the lack of color change on the fluid (yes, it is diesel compatible fluid) and not seeing or hearing of many people having to do gaskets again after studs is making me second guess our diagnosis.
My question is: Have any of you out there had many heads/gaskets leak after they are studded? OEM gaskets were used when it was done too. Is there any other way I could be getting this kind of pressure that quickly in my cooling system? And have any of you re-used ARP studs?
I plan on calling ARP today and seeing if I can get some info on the re-use of the studs. And I heard from another friend that ARP actually recommends re-torquing of the studs after some use on them. Has anyone heard of this before? This would be one big PITA on a 6.0 if this was the case.
Thanks in advance for any/all replies!
Last edited by 6.0rigrocket; 02-28-2013 at 07:56 AM.