Adding head studs to a diesel

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I was thinking of putting head studs in my truck. I got a guy who does good work, but I'm not sure if you're supposed to do this. He said you can just remove a bolt and replace it with the stud.

Maybe he explained it wrong. Can you remove all the bolts and just put studs in and keep the same head gasket? My head gasket isn't blown, just want to do some preventative measures.
 
Mostly I'd check the TQ on the existing bolts. New VC gasket. Any adjustments needed while I was in there. If the bolts TQ down and they were off by less than 10#, I would not worry. If one or two are off by more than 10#, THEN you think another clamping strategy ...

Now, on some engines, if you rotate the head bolts, they will weep coolant. Don't know if this is one of those engines ...

Studs are a different animal. They usually go in with a mild thread locker so they won't rotate once installed and the nuts will. But, this is all something to be discussed with your technician ...

And a lot of this has to do with the thread depth into the block deck, how much distortion the bolts cause vs studs, etc. It's not cut and dry ...
 
You can replace them one at a time if the gasket isn't blown, IF this is a stock engine with no modifications......It's a waste of money!

On my 1997 Dodge 12 Valve running 35 PSI, TST fuel Plate, Cranked AFC Wheel......I popped the heads off 2 head bolts pulling a grade with 13,0000 pounds. Smelled coolant & limped it to a parking lot, Cleared the coolant from the bolt holes, Sent my wife to Cummins to buy 2 bolts, Torque them back down & didn't change the head gasket 'til 8 months later.

My current Duramax has 380,000 plus miles on it with stock bolts....I learned my lesson trying to tow heavy with modified engines!!!

If want to spend money on your 6.7L ISB.....Put some genuine Bosch reman Injectors in it IF it has over 150,000 on it!!!!
 
Originally Posted By: clinebarger

On my 1997 Dodge 12 Valve ..................I popped the heads off 2 head bolts


That's pretty wild... never heard of that before
 
Originally Posted By: Linctex
Originally Posted By: clinebarger

On my 1997 Dodge 12 Valve ..................I popped the heads off 2 head bolts


That's pretty wild... never heard of that before


If I didn't witness it....I would have a hard time believing it myself. I was pushing it really hard....Had to almost stop at the bottom of the grade & lost all momentum. I sure don't miss that NV4500!!!
 
Originally Posted By: clinebarger
You can replace them one at a time if the gasket isn't blown, IF this is a stock engine with no modifications......It's a waste of money!


^^^^This

If its a Ford, the last couple near the firewall won't go without cutting clearance in the firewall.


Edit, I see your sig is a dodge.
 
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Originally Posted By: motor_oil_madman
Do you have to remove head bolts/studs to replace injectors?


No. They just have an injector clamp that holds them in the head.

Do you have some bad injectors? Common rail diesels don't need larger injectors for big increase in HP and torque. If you have injector issues, you may want to upgrade your fuel filter situation. The OEM big 3 don't set up their trucks right with filter systems. That's why the common rail injectors have issues.
 
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Yes, it's been done this way too many times to count on 6.7 engines.

Not bad to have as preventive maintenance, but hardly necessary. I would also vote for getting new injectors and a CAT filter setup first. Dropping an injector is baaaaaaaaaaaaaad news.
 
Originally Posted By: clinebarger
Originally Posted By: Linctex
Originally Posted By: clinebarger

On my 1997 Dodge 12 Valve ..................I popped the heads off 2 head bolts


That's pretty wild... never heard of that before


If I didn't witness it....I would have a hard time believing it myself. I was pushing it really hard....Had to almost stop at the bottom of the grade & lost all momentum. I sure don't miss that NV4500!!!



What was wrong with the NV4500?
 
Originally Posted By: DoubleWasp
Yes, it's been done this way too many times to count on 6.7 engines.

Not bad to have as preventive maintenance, but hardly necessary. I would also vote for getting new injectors and a CAT filter setup first. Dropping an injector is baaaaaaaaaaaaaad news.


I'm at 120,000 miles and like 5300hrs. Chrysler put out an upgraded filter for this engine back in 09 i think. It filters 100 percent at 5 microns and like 95 percent at 3 microns. Still not the recommended minimum of 3 microns that Bosch recommends but pretty close.
 
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I would not trust Ford, GM, or Chrysler for a fuel filter for a high pressure fuel injection system. The injectors at stock tune settings see in the range of 22,000 to 25,000 psi at the nozzle. To boot, I most certainly would not trust Bosch/Botch because it seems as if most of their common rail diesel injectors have issues.

If you are going to keep your truck long term, a good investment would be a 12 micron water separator with a lift pump followed by a 2 micron Cat filter. Using the large class 8 style truck size filters. The filters would give you almost lab quality fuel, and the lift pump will save your cp3 high pressure fuel pump. Its the small fine dirt, debris that erodes the injector ball and seats. You can probably do the job for a little over what 1 injector cost's.
 
I don't trust the remanufactured injectors. I hear lots of problems with those. Apparently the only way to get a new set is buy a new truck.
 
It's only at 23,000 at full throttle. Then I believe that's the fuel rail, so you divide that by the number of injectors. I could be wrong about that part though.
 
Originally Posted By: motor_oil_madman
I don't trust the remanufactured injectors. I hear lots of problems with those. Apparently the only way to get a new set is buy a new truck.


I don't have issues with genuine Bosch remans, It's ALL about the install!!!! Absolutely critical to be as clean as possible. One grain of sand can ruin an injector!!

Some of the CR Dodge's I see come from other shops with misfires/hard starts after injector replacement have the "Transfer Tubes" Over or Under torqued. The others are just a dirty install.

I guess I'm glad I cut my teeth on LB7 Duramax's.....You want to talk about a JOB!!
 
Originally Posted By: motor_oil_madman
It's only at 23,000 at full throttle. Then I believe that's the fuel rail, so you divide that by the number of injectors. I could be wrong about that part though.


All 6 injectors receive Rail Pressure, That's why it's called Common Rail.
 
Originally Posted By: Miller88
Originally Posted By: clinebarger
Originally Posted By: Linctex
Originally Posted By: clinebarger

On my 1997 Dodge 12 Valve ..................I popped the heads off 2 head bolts


That's pretty wild... never heard of that before


If I didn't witness it....I would have a hard time believing it myself. I was pushing it really hard....Had to almost stop at the bottom of the grade & lost all momentum. I sure don't miss that NV4500!!!



What was wrong with the NV4500?



Wide ratios coupled to a engine with a very narrow power band, I was meaning to put Governor Springs in.....But, The Gear Case to Block gasket gave up at about 270,000 miles & it had a leaking oil pan gasket so it was time to trade it in.
 
Originally Posted By: motor_oil_madman
Originally Posted By: DoubleWasp
Yes, it's been done this way too many times to count on 6.7 engines.

Not bad to have as preventive maintenance, but hardly necessary. I would also vote for getting new injectors and a CAT filter setup first. Dropping an injector is baaaaaaaaaaaaaad news.


I'm at 120,000 miles and like 5300hrs. Chrysler put out an upgraded filter for this engine back in 09 i think. It filters 100 percent at 5 microns and like 95 percent at 3 microns. Still not the recommended minimum of 3 microns that Bosch recommends but pretty close.


It's a major upgrade over what they were using, but the CAT filters are even more superior.

Fortunately, it's Fleetguard and not Chrysler responsible for the filter.
 
Originally Posted By: clinebarger



Wide ratios coupled to a engine with a very narrow power band, I was meaning to put Governor Springs in.....But, The Gear Case to Block gasket gave up at about 270,000 miles & it had a leaking oil pan gasket so it was time to trade it in.


To me, these engines were always in need of an 8 speed. Basically, a close ratio 6 speed gearbox, plus a granny low 1st gear, and a tall overdrive for 8th gear.

Gears 1-6 beginning with the Nv4500's second gear ratio, and ending with its 5th gear ratio, with closely spaced gears in between. Would likely have flipped people out though, to see a stick with 8 shift positions listed.
 
Why? It's a Cummins. Just maintain it and run it especially if it isn't heavily modified. On a 6.0 PSD I could see doing head studs as a preventative, but the head gaskets aren't a problem on the Cummins engines.

Taking the bolts out and replacing them one by one isn't something I would do either. Unless you have a head gasket problem I would leave it alone.
 
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