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08 6.7L Slight Build (Blown HG)

4.9K views 34 replies 11 participants last post by  SpeedyWs6  
#1 ·
Hey guys and gals,
I just picked up a 08 Mega Cab with a G56. "Luckily" for me it blew the Head Gasket while the previous owner still had it so it helped with the price a little, and has forced me to start wrenching on it before I start driving it.

Here is the parts list for it:
ARP's
Push Rods
Hamilton Valve Springs
Decked Head
lazarsmith gasket
Anarchy diesel 2nd gen S467.7 Billet kit
BD Exhaust brake
Exergy 60% Injectors
Exergy 10 mm pump
FASS Pump
Anarchy Tuning
Insight CTS

Does any one have the Pac Brake loadleash? I hear they are coming out with one for the manual transmission, I wish it wasnt connected via OBD II. Has anyone used the OBD II splitter thing to plug two devices in? Or how do the load leash by Pac Brake work for you's?

Thanks!
 
#6 ·
I had the head decked and I need 0.010" HG to make up for what was decked off of it.

load leash will work with any exhaust brake or the VGT, but they are currently making one that is more stand alone and will not require any modifications.

the truck has a SBDD3850 in it already.
 
#3 ·
Blacks diesel sells a 2nd gen swap with an exhaust brake.. There was a few videos floating around a while back!
 
#4 ·
That load leash will not work without the vgt along with it. It's not an actual jacobs engine brake, it's just a bleeder style brake.
 
#7 ·
It will work without the VGT if it has an exhaust brake installed. It will just take some modifications. Pac Brake is working on one now that will do exactly what I want it to do too.
 
#8 ·
Studs, springs, push rods, lift pump on order today. Injectors and injection pump tomorrow, along with second gen turbo kit this week.
I am anticipating 750ish hp, and hope I don't spit out a rod....
 
#10 ·
My build with what's in my Sig done 757 and 15xx torque.
 
#11 ·
Interesting. I would be happy with that. It will be interesting to see the difference with a mod'd pump. Also I guess there is a difference with the tuning. What do you feel is holding you back from more? Tuning? air? fuel? rods? lol
 
#12 ·
Air is my hold back most definitely. But my tow tune is 680hp and 1300 and some change lbs of torque. Dont take me wrong though cause my 757 is deffinatly a little hot for my turbo, but my set up would be a great mid 600 daily driving build that wouldnt run hot at that level and im sure live a long time not being near maxed out. I seen the dyno sheet for a guy with my same build but just bigger housing on his 72 and it put down 850hp. But he only had 3 more lbs torque then I did and put it down about 200 or so rpm farther in the rpm curve then mine. I'd like to maybe next year throw a 591 under my 72 for a twin set up and put some rods in and shoot for 1,000. But that is still on the wish list lol.
 
#13 ·
So I have the studs, springs, push rods, lift pump, HG, injectors and cp3. Just waiting on the turbo setup from Anarchy which is to be in on Monday. I already have the tunes from Anarchy though.
With a bit of reading I think I am going to get a valair triple disc and lazarsmiths trans brace. Obviously need to add traction bars to attempt to keep the rear end planted.
So up next will be monitoring electronics (edge stuff) then the brace and bd remote exhaust brake and traction bars. When I get back out to Calgary I hope to make a trip down to GFP and get some air flow upgrades.
Lastly if I can find all required material to swap in an FSO-8406A fuller 6 speed I hope to do that before I grenade the G56.
 
#14 ·
So I want to run a back pressure sensor on my CTS, what do I need to do to not "burn/melt" the sensor. I have seen them before with almost a copper coil spiraled a bunch of times and then go into the pressure sensor.
Is this correct? Anyone know where I can get the material from or what it is exactly that is used?
Thanks in advanced!
 
#15 ·
So I got my BD Exhuast brake on order... they are on back order, what the he11. So this weekend I had some spare time so I made a rip down to GDP and got a bunch of goodies from Richard, thanks again for meeting me on a saturday.
From GDP I got the ccv breather, air boss, S-2 intake manifold, intercooler pipe, boost boots, and a remote grid heater. So hopefully I can get everything out of this S467.7 and not be restricted by the stock stuff.

I really want to know what I need to do to run a back pressure gauge on my CTS, someone must be running one somewhere.....
 
#16 ·
Exhaust brake is in, finishing up the wiring for the gauges on the CTS. need to get it warm and do the last stud re torque and its good to go!

Test drive is tomorrow night!
 
#17 ·
who knows what is the easiest way to upload pictures that are on my phone?
 
#19 ·
I recently blew my head gasket on my 2008 6.7 come to find out it was from the vgt turbo so I would recommend changing your manifold and turbo while you have I tore apart. I did 425 arp studs with full sinister gasket kit and sold my smarty and also did the level 1 tuning from anarchy diesel. he sells the the second gen swap kits for a fair price. im running the s467.7 swap on mine and its incredible an worth every dollar.
 
#20 ·
Manifold is off, Phil's S467.7 is on, has every glacier diesel air improvement possible, exergy 60's and 10 mm pump, anarchy tuning, BD exhaust brake, and ARP's installed.

Looking forward to tonight!
 
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#21 ·
I havent been able to find a 467.7 with a bd exhaust brake sound clip, any chance you can get a video? I have only had the 467.7 two weeks but i do miss the exhaust brake. how do you like it? any down side?
 
#22 ·
Well late last night I got the truck out for a rip. Runs strong obviously, but it was raining, so traction was obviously an issue. I also have a CEL for a U010C and I emailed Phil and he responded right away. It was even later at night. Customer service is great!

I have the exhaust brake installed but still need to get the push/pull switch in from BD. I do not want to cut a pointless hole in my dash. Over the next couple days I hope to get pictures, videos etc up and will be sure to do a review on the exhaust brake.
 
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#24 ·
So I have been half way across the country during most of this build which has slowed things down DRASTICALLY! it was all together back around the time of the last posts. It made it maybe 200 km and the head gasket let go again. So now I ditched the ARP 425's, and went with ARP 625's, got a Haisley Fire Ring head gasket kit and had the head cut for rings. It should be good to go come christmas time! will be a great present!

Here is a list of the mods as it stands:
-ARP Head Studs 625
-Decked and fire ringed head
-Haisley Machine Fire Ring head gasket
-Hamilton Cams 103 LB Valve Springs
-Hamilton Cams Heavy Duty Pushrods
-60% Exergy Injectors, not just the nozzles, full balanced injectors
-10mm Exergy stroker pump.
-Anarchy S467.7 2nd gen kit
-BD remote mount 4' Exhaust brake with push pull switch mounted to manual shifter
-FASS 150 GPH titanium lift pump
-Edge CTS
-Edge Turbo Timer controlled by the CTS
-4 relays for switches controlled by the Edge CTS
-2 Edge pressure sensors one for Turbo Drive pressure/exhaust brake back pressure, one for fuel lift pump to CP3 pressure
-EGT Sensor for Edge CTS
- 0-100 PSI Pressure sensor for rear air bags displayed on Edge CTS
- Rear air bags are filled by pressing a button on the Edge CTS that activates a relay/solenoid to fill the rear air bags
-GDP Air boss
-GDP intake horn
-GDP inline grid heater
-GDP Crankcase breather
-Anarchy Diesel EFI Live tunes
-Snow Performance Water Meth Injection MPG MAX (incase it gets warm pulling heavy)

I think that gets most of it.
 
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#25 ·
So this F**king truck...
Seems to be running fine again but I have a list of codes now.

P0118
P0128
P0217
P051C
P2269

I also have my washer fluid level low on the O/H display.

I think my thermostat is screwed and stuck shut. I have no heat in the cab, the system is pressurizing and coolant in the rad is slowly getting warm. The hose from the rad to the thermostat gets hard but not hot.

I unplugged the ECT sensor and the temp gauge never moved but the CTS Displayed a different value and corrected itself as soon as I plugged it back in.

Is it possible I have a wiring issue? Maybe a ground issue? or is it a possible ECM failing?

I really wish I had a way to view the logic in the ECM to know what triggers all of these and what it takes to re set them. Also where the pins are to test everything would be amazing, does this document even exist?
 
#26 ·
someone must have an idea.....

Is it also possible I am getting no circulation from the pump if I have no heat in the cab? Does anyone have a drawing how the heating core loop is tied into the block and how the water pump affects this loop? Like does the thermostat need to be open before there is flow through the heater core?

It sounds to me like I have a couple issues but its looking like I also have a screwed water pump. anyway to test and confirm instead of throwing parts at it?

Thanks guys and gals
 
#27 · (Edited)
Heater core is on the bypass loop, circulates water regardless of thermostat position, cools the turbo controller too so be careful..... Sounds like you sheared the pin on the impeller and she is windmilling..... Never mind I see you have a 467..... No way to test water pump except to pull it and make sure the spiny thing don't spin when you hold the pulley .
 
#28 ·
ok, thanks for the info. sounds like that is my issue too. What causes the pin to sheer off?
What causes the pin to sheer off?

Where does the temp gauge get its info from? When I pulled the ECT sednsor right by the thermostat the CTS was reading 190 F (88 C) but the gauge was showing 140 F (60 C) (as low as the gauge goes)

If I have what appears to be soot in the coolant I would assume my head gasket is still blown?
 
#29 ·
ok, thanks for the info. sounds like that is my issue too. What causes the pin to sheer off?
What causes the pin to sheer off? piss poor luck......

Where does the temp gauge get its info from? When I pulled the ECT sednsor right by the thermostat the CTS was reading 190 F (88 C) but the gauge was showing 140 F (60 C) (as low as the gauge goes) there may be a second sensor the ecm/dash gets its info from... does you dash temp move at all?

If I have what appears to be soot in the coolant I would assume my head gasket is still blown?
could be left over from last blown gasket.
 
#30 ·
I took it for a drive (maybe 30 miles) and I had to push on it pretty hard to get the temp gauge to move at all. I saw a bit of a change on the cts but it will read a lot lower.

Sounds good on the water pump pin.

I hope it is left over from the previous gasket.....

What are the odds I have a cracked block? I had a very competent machine shop look over the block and prep it. The same shop machined the head for the Haisely Fire Ring gasket.

I had a reputable shop install the head.... I didnt notice soot before when I first drove it but I see coolant now....
 
#35 ·
I replaced a 6.7 due to a cracked block. I never could find the crack. We pressure tested the head and replaced the gasket twice before we put a short block in it.