Engine/Transmission (1998.5 - 2002) ARP Stud questions??? Retorque?

[GOT-Torque]

Two questions:



1) Is the bolt hole in the block open to the engine internals? Meaning, if you use a tap to extend the threads, could the shavings end up in the engine oil? I assume since you have to use a bottoming tap, it means the hole has a bottom and the shavings can't go anywhere? If so, I don't have a problem using a shop vac and small tube to clean out the shavings, however if I am going to risk getting shaving in the engine oil I would be very leary of doing this.



2) I plan to install the studs without removing the head and leaving the stock gasket in place. When should I retorque the head studs or is it even necessary since I'm not using O-rings?



Any tips or procedures for installing the studs?



Thanks for you help.

 

[Wyatt 1]

If I remember correctly you will have a time with the back headbolts without jacking up the body off the frame. When I installed mine I had the head off and to put the head back on I had to jack the body up, something like that, take a hard look at the back of the head close to the fire wall that lip that sticks out is the problem. Dont know what to call the lip, where the windshield wipers are at???

 

[jwilliams3]

No the holes in the block are blind.

 

[SKneeland]

the back bolts are tight, but i did mine without any drastic measures (or tapping anything for that matter)



left the head on the block and followed the torque pattern one bolt at a time



then retorqued all again



drove it for a day, retorqued & reset valves

 

[Todd T]

you can take the head bolts out one at a time and install the studs and torque them.



The bolt holes are all blind, but you should chase the threads with a blind/bottoming tap to make sure you get the studs all the way in the block.



if doing it one at a time you dont really need to follow a torque sequence. I'd suggest running it up to temp and re-torquing after you are all done though.



Wyatt 1- the cowl! You jacked the body up? what were you thinking? or were you?? just set the head on, lube the studs, set'em in, screw'em in, lube the washers and nuts and install them and torque to spec :-laf



I heard of a guy superglueing his fire rings into the head to install them too. OH-MY-GOSH!



uuuhh McFly, that stuff dries hard and takes up space that wasnt accounted for when cutting the grooves

 

[GOT-Torque]

So after installing the studs, and readusting the valves. Bring it up to temp, let it cool back down and then retorque, readjust valves, and call it good?



Thanks for all the responses.



All of this work (having the valve cover off) is just my excuse to install the new MACH 4 injectors I'm buying with the studs



Anyone need a low mileage set of DDII's?

 

[Jetpilot]

I prefer to replace the studs one for one using the cummins torque sequence. Use a bottum tap and be sure the holes are tapped to the bottum. Then use a shop vac with a tube to clean out all the shavings. Bottum the studs out in the block and back out 1/2 turn. Don't lube the bottum of the studs threads but be sure and use lots of lube on the top threads, washer, and nut. Torque to 125# and reset valves. You really don't need to do a retorque since no rings were installed. Also the longer studs go on the outside towards to exhaust manifold.



Doug

 

[Todd T]

Hey Doug, has ARP changed their studs since March of this year? Mine were all the same length and the white sheet that came with them said to torque to 100lbs using their molly lube which was supplied or 120? (Don’t recall for sure) if using motor oil.



A torque to yield bolt like head studs have a tensile strength of X, once you reach that desired stretch, over tightening (preloading) at this point is setting you up for a good old fashioned tensile overload failure. Either the fastener itself will neck down and fail or the block threads will pull out. ARP's have a higher Rockwell rating which attributes to a higher tensile strength than the brand X studs other vendors might sell that do torque to 120-125lbs. Therefore the ARP’s stretch less, having a lower torque setting but still have as much, if not more, clamping pressure.



Caution should always be taken when you torque and you should follow the spec sheet for that bolt manufacturer.



I've argued this with Brad at Scheids, he keeps telling me to torque my ARP bolts to 120lbs using the molly lube. I won’t do it. Having a metallurgist/machinist in the family has taught me to not always trust outside information.



ON EDIT: I just checked and the ARP 24v (247-4202) kits for our trucks are the 12mm ARP Pro series (220,000 PSI, heat treated) bolts and should be torqued to the following:



122ft lbs using 30wt oil

96ft lbs using ARP (molly) lube



They should be run through 5 cycles before final torque is applied.

 

[Wyatt 1]

Wyatt 1- the cowl! You jacked the body up? what were you thinking?



Todd you make it sound like it was alot of extra work?? 4 bolts no problem I already had the truck torn apart to put the cam in. It sure made it a hell of alot easier when I put them in, but from the sound of you probably know more about anything than I do.

 

[GOT-Torque]

Todd T:



What does the 5 cycles thing mean? Five heat up / cool down cycles?

 

[Todd T]

from the sound of you probably know more about anything than I do.

The day I start to believe that is the day I discontinue to learn anything further in life and I'm too young to start thinking like that I just found it odd for you to lift the body rather than install the head and then the studs when facing that obstacle.



5 cycles: The lubricant has to have a chance to be evenly distributed through the thread edges before it can give an accurate torque reading without catching or ratcheting on the thread edges. They (ARP) call for five cycles for this using the molly lube. That means you have to bring it to just tight back it off and re-tighten 5 times then apply torque to spec.



It's doubtful anyone less than a aircraft mechanic ever does these steps though. I just relayed what the nice fella at ARP told me for the torque procedure.