engine goin under the knife

Finch

Finch

5150
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Mar 14, 2009
Messages
148
the truck came up with a knock over the weekend, took it to a buddies shop and confirmed it was a wrist pin that was going out...my question what should i have done wile the head is off? later plans involve twin and a lot more fuel

stuff so far
o rings/HG
studs
injectors cleaned/checked
port n polish, possible exhaust seats
 
Id say if its an early 04 to get the larger valve seats right away. No reason to do this all twice. Id say grab some valve springs and keepers too if budget allows.
 
I'd run a stock mls and arp 625's. I'd also do as Chris says and install oversize seats to ensure they stay put. The stockers with high mileage and power aren't trustworthy.
 
TheBigNasty said:
I'd run a stock mls and arp 625's. I'd also do as Chris says and install oversize seats to ensure they stay put. The stockers with high mileage and power aren't trustworthy.
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nothing right now is in the budget, i just don't want to pull the head again.

is there a different in the 425's vs 625?
the 425's are rated to 220,000 tensile strength, 260 for the 425's

anything special to the seats or just a hair oversize?
 
The seats are .005" oversize and frozen before they are installed so they will fit. The 625's will control your head better with the extra clamp force. The typical reason a MLS gasket fails is because the head lifts. I like them because usually even if you lift the head it will reseal itself. It won't be as good as new but it will still hold alot, whereas a 12/24v gasket is typically destroyed and you are stranded.
 
TheBigNasty said:
The seats are .005" oversize and frozen before they are installed so they will fit. The 625's will control your head better with the extra clamp force. The typical reason a MLS gasket fails is because the head lifts. I like them because usually even if you lift the head it will reseal itself. It won't be as good as new but it will still hold alot, whereas a 12/24v gasket is typically destroyed and you are stranded.
Click to expand...

ahh, gotcha, just on the exhast side?
 
TheBigNasty said:
The seats are .005" oversize and frozen before they are installed so they will fit. The 625's will control your head better with the extra clamp force. The typical reason a MLS gasket fails is because the head lifts. I like them because usually even if you lift the head it will reseal itself. It won't be as good as new but it will still hold alot, whereas a 12/24v gasket is typically destroyed and you are stranded.
Click to expand...

Couldnt agree more here!
 
i was chatting with Tim Barber about cylinder head differences, he recommends on the 03/04 motors that if you pull off the head, replace it with a 05/06 head. better valve seat material,better valves and port design. i would say start off with a 05/06 head then have the work done, since you are planning on compounds later go with 625's or the A-1 H11 studs.
 
Boostediesel said:
i was chatting with Tim Barber about cylinder head differences, he recommends on the 03/04 motors that if you pull off the head, replace it with a 05/06 head. better valve seat material,better valves and port design. i would say start off with a 05/06 head then have the work done, since you are planning on compounds later go with 625's or the A-1 H11 studs.
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how much of a difference vs a 04 port/polished head?

also, where is the best place to get o rings and a HG?

thanks again guy for all the insight and advice
 
i dont know the flow differences between a ported/polished head versus a potrted /polished 05/06 head, but from what he was explaining to me was the port design specificly in the 06 head was less restrictive than the 03/04.also from he was explaining is the 05/06 heads have the inconel exhaust valves, so basically you are starting with a better platform with 05/06 head.
 
truck is coming apart tomorrow, really looking forward to driving it again... last question, what should i torque the head studs to? 125? Thanks guys
 
dangerous06 said:
yup do it 3 times!
Click to expand...

i found instructions on here some where, forgot who wrote them:


Torque the head to Cummins spec
Step1- all bolts to 66 ft.lbs.
Step2- recheck all bolts.
Step3- all bolts to 89 ft.lbs.
Step4- recheck all bolts.
Step5- rotate all bolts an additional 90degrees-(bolts) if using Studs torque to-125 ft.lbs.
Check valve clearance when done.
Bring engine up to operating temperature(without driving!)
Let engine cool down to about 95degrees to begin Line Torque Procedure.

To line torque head:
Make a mark with a magic marker, so you have a reference point on top of the bolthead or nut(studs).
Then start at the front(pass. side of head) bolt/stud-nut, loosen it up, then re-torque it to 125 ft.lbs.(studs) 90ft.lbs.(bolts.)
Proceed down that line of bolt/studs, doing same thing, one at a time.

*NOTE*
If you notice more than 1/8th inch rotation of the bolt while doing last step, then you may have a bolt that has 'stretched'
You need to pull that one out and measure it with a Cummins Bolt Guide, or Bolt Stretch Indicator.

Do not forget to re-check valve clearances once procedure is done.
Intake : .010"
Exhaust : .020"


Drive truck for the next week but keep the boost psi under 30psi during this time. (crucial)
By doing this,the different heat cycles will get the head to 'settle' better.

After a weeks time has passed, do the Line Torque Procedure again. Same exact way you did the first time. Drive it again for a week. And you can get into the pedal a little bit more but don't go maxing it out just yet.

After a weeks time has passed again the head should have settled by now and you can do the last line torque procedure and you should be good to drive it HARD. (as long as you don't see any movement from your marks.)
 
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