ARP head studs

racertracer · **Posted:** Thu Apr 25, 2013 3:31 am

LMWatBullRun wrote:

There should be a hardened high strength washer to spread the load and reduce the bolt to head friction. If the bolts were about 7 mm longer, and we had a high strength washer, I think you might get good results re-using the bolts,

That is good information and if it fixes the problem with little or no additional costs, some may choose to reuse the bolts.

Here's my thoughts; while the head is off and at the shop being tested, have it worked on to accept the washers if it passes as being re-usable. The head will always require testing after a HG leak, so while it's at the shop have the work done.

Have the shop remove 7mm of material around the hole so that a hardened washer can be installed and the existing TTY bolts can be reused.

Chase and clean the threads in the head and on the bolts, procure ARP lube to use at reinstall.

Reusing the existing TTY bolts with a hardened washer may not be as strong as the ARP studs, but it may be just enough to fix the problem, thoughts?

LMWatBullRun · **Posted:** Thu Apr 25, 2013 8:47 am

Hmmm.

A few issues come to mind:

Cost of machining 18 recesses is likely to be non-trivial.
Also, don't know whether you could deepen the recess by the washer thickness
and not weaken an already weak head too much. I do not know what is under the washer recess, but there are cooling passages down there.....

It would probably cheaper to buy bolts a bit longer than to do the machining.

Also, while the washers will reduce head galling and improve clamping, you still have the issue with coarse threads in the block inducing significant variance.

Bottom line, if you are going to stay with bolts and add washers, I would buy longer bolts.

But I still think that studs are a better solution, and the added cost for those is small next to the costs of a top end overhaul.

kjjet · **Posted:** Thu Apr 25, 2013 8:55 am

LMWatBullRun wrote:

Hmmm.

A few issues come to mind:

Cost of machining 18 recesses is likely to be non-trivial.
Also, don't know whether you could deepen the recess by the washer thickness
and not weaken an already weak head too much. I do not know what is under the washer recess, but there are cooling passages down there.....

It would probably cheaper to buy bolts a bit longer than to do the machining.

Also, while the washers will reduce head galling and improve clamping, you still have the issue with coarse threads in the block inducing significant variance.

Bottom line, if you are going to stay with bolts and add washers, I would buy longer bolts.

But I still think that studs are a better solution, and the added cost for those is small next to the costs of a top end overhaul.

I Totally agree!!

audiboy86 · **Posted:** Thu Apr 25, 2013 2:16 pm

Acttualy the cost difference is slimmer then most think 291.06 shipped for the studs 112 shipped if you know who to ask on the forums so it come out to 403.06 shipped to your door. Where the stock set up will run you +260 shipped to your door. So do i think that 140 is worth the peace of mind yes do i want my jeeps motor to be the least of my worries on the trail absolutely. So mine will be getting the head stud set up and the new metal glow plugs from overseas (cant recall the name to save my life :banghead:

) and hopefully i will be done till time for some upgrades.

LMWatBullRun · **Posted:** Fri Apr 26, 2013 5:52 pm

For those folks who do not yet have overt leaky HG/warped head but who do not want to pay for studs, the washers can be had from ARP, and I am sure that bolts 5 mm longer can be had too. Smoothing the head bolt recess by reaming off the ridge could be done by hand using the reamer R2.0 suggested, and cleaning the block threads and using ARP lube would result in much better than factory clamping force. But as Audiboy points out, you are not going to spend much more to get much better performance with ARP studs.

If I simply could not afford new bolts or studs, but knew I might have a problem, I think I would use ARP lube on the threads and heads of the existing bolts and reinstall using the turn of bolt method in the FSM. I'd do that with a torque wrench, and any low torque bolts would get some more rotation.

dthdcrd · **Posted:** Sun Jun 02, 2013 8:25 pm

Just finished this job over the weekend. Thanks to this thread, Larry and many other useful bits of information from this forum.

Let me say I am not an experienced mechanic but am far from the average do it yourselfer. I did work in a garage for two years. Service many of my own cars and have friends in the business that provide tools knowledge etc..

I did the stud replacement because on two occasions while towing, long upgrade, maintaining steady boost, 18lbs or so, coolant made its way into the overflow. It was my belief that just enough (mili second) pressure escaped into the coolant and pushed it out. I have other reasons but don't need to get into all. The fact is this is a good thing if it works or not.

The job took me 9hrs. This was with the right tools in an auto repair shop. A Porsche, Audi, Volkswagen, master tech a lift away to help with any questions etc. I was moving at a good clip.

Just wanted to give a perspective on this for anyone looking to tackle it. Take your time, pay attention and get stuff out of your way to make it easier to work. It is not something to take on if you have never done something like this before IMO.

LMWatBullRun · **Posted:** Tue Jun 04, 2013 9:33 pm

Thanks for the post, DTHDCRD and I am most interested to see whether this solves your coolant loss problem.
This is how this engine should have been put together from the start, IMO; a commercial grade wet cylinder sleeved motor with cheap "TTY" head bolts? Why machine the head with a recess if not for a high strength washer? Anyhow, I think you are the fifth person I know about to do this; I was the second, but I did not know anybody else had done it until after I had.

cmpbiker · **Joined:** Mon Mar 29, 2010 1:26 pm **Posts:** 62

I am starting to get some bubbles in the coolant along with it eating up antifreeze so I am in need of a fix. It really is just one money sucking event after another isn't it?

Would one of you smart people feel inclined to write a quick step by step to get to the point where we can replace the bolts with studs? I know my way around an engine but don't know enough about the VM to know what needs to be removed and what can be worked around.

Thanks!

papaindigo · **Posted:** Mon Jun 10, 2013 12:40 pm

Go to viewtopic.php?f=98&t=75479 for a writeup on rocker/lifter replacement that covers how to get far enough in to get to the head bolts.

LMWatBullRun · **Posted:** Sat Jul 06, 2013 10:21 pm

dthdcrd wrote:

Just finished this job over the weekend. Thanks to this thread, Larry and many other useful bits of information from this forum.
Let me say I am not an experienced mechanic but am far from the average do it yourselfer. I did work in a garage for two years. Service many of my own cars and have friends in the business that provide tools knowledge etc..
I did the stud replacement because on two occasions while towing, long upgrade, maintaining steady boost, 18lbs or so, coolant made its way into the overflow. It was my belief that just enough (mili second) pressure escaped into the coolant and pushed it out. I have other reasons but don't need to get into all. The fact is this is a good thing if it works or not. The job took me 9hrs. This was with the right tools in an auto repair shop. A Porsche, Audi, Volkswagen, master tech a lift away to help with any questions etc. I was moving at a good clip. Just wanted to give a perspective on this for anyone looking to tackle it. Take your time, pay attention and get stuff out of your way to make it easier to work. It is not something to take on if you have never done something like this before IMO.

Any updates?
There are a number of folks that have apparently decided to do this, any after action reports?

audiboy86 · **Posted:** Sun Jul 07, 2013 10:58 am

I have them installed and have about 1k on the motor without and issue.

racertracer · **Posted:** Sun Jul 07, 2013 11:47 am

I would like to know what VM Motori has to says about installing a hardened washer with the existing TTY bolt, to increase the clamping area.

I plan to again contact VM Motori to see what they have to say about adding a hardened washer to the existing TTY bolts without any other work to the head along using the ARP Lube.

LM you suggest a 7mm but could a lesser thickness apply.... arriving at a happy medium for both new washer and OEM bolts.

I am suggesting not procuring new bolts at all, but to reuse the existing ones.

VM Motori has probably had enough of me, by now.

Thoughts!

LMWatBullRun · **Posted:** Sun Jul 07, 2013 2:13 pm

racertracer wrote:

I would like to know what VM Motori has to says about installing a hardened washer with the existing TTY bolt, to increase the clamping area.

I plan to again contact VM Motori to see what they have to say about adding a hardened washer to the existing TTY bolts without any other work to the head along using the ARP Lube.

LM you suggest a 7mm but could a lesser thickness apply.... arriving at a happy medium for both new washer and OEM bolts.

I am suggesting not procuring new bolts at all, but to reuse the existing ones.

VM Motori has probably had enough of me, by now.

Thoughts!

If you are going to add a washer, you will need a longer bolt to compensate for the washer thickness if you wish to maintain the same thread engagement in the CI block. Given that the ARP washer is about 2 mm, and given that there is extra thread in the hole, I thought it would make sense to buy new TTY bolts, from 5 to 7 mm longer than stock. I have not done any calculations on thread engagement requirements, as the studs match the factory engagement. It may well be that you still have plenty of margin by using the factory bolts with ARP washers, but *I* do not know that. More engagment is better than less.

For under 350 bucks you can have studs and no worries. Save the bucks and buy the studs, is what I say.

Now VM Motori, the evidence to the contrary notwithstanding, is never going to admit that their engineering was anything less than stellar for this engine. You are wasting your time in attempting to get them to agree to any modifications to their 'perfect' motor.

Smacker · **Posted:** Thu Sep 05, 2013 11:22 am

Any updates?
There are a number of folks that have apparently decided to do this, any after action reports?

Installed the ARP studs a couple of weeks (300 Miles). ago along with timing belt, tensioner, serp belt, water pump, pulleys, fan clutch w/ nylon fan and 7 volt glow plugs. all went well and still wondering if I cured the loss of coolant. Had to top off coolant a few times and kind of expected that. Most interesting development was the sound of the engine. It went from tractor like to smooth and solid like our Grand Cherokee CRD. Very pleased so far but the jury is still out on the Italian Steamer.

bugnout · **Posted:** Thu Sep 05, 2013 3:23 pm

Just started yesterday. Plan on putting in significant time this weekend to get it all apart, order any parts I missed and get the ECM reprogrammed by GDE for the 5V metallic GP's. Next weekend I'll be putting it all back together.

racertracer · **Posted:** Thu Sep 05, 2013 6:27 pm

I contacted VM Motori again today to see if they could respond to my request for information.

I want to know if we could use the existing oem TTY bolts with a hardened washer without any modification to the block or oem bolt.

Diana Dupuie of VM NA said that she will have a tech get back to me. I followed up with an email to her.

So we shall see.

racertracer · **Posted:** Fri Sep 20, 2013 6:11 pm

I received an answer from Diana Dupuie of VM Motori NA and as expected here is the response:

" Sorry – No one at VM Motori or VM North America can endorse any changes that you may want to make. They suggest that you go on to the Jeep Liberty’s forums asking if anyone has ever done what you’re asking or if they recommend it. Sorry we couldn’t help more."

geordi · **Posted:** Fri Sep 20, 2013 7:20 pm

So she suggests asking us for advice about her company's motor?

Cute.

Is it just me, or does that really show what kind of knowledge they DO NOT have about their engineering? That is the sort of response I would expect from a dealer, not from the engine maker.

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WolverineFW · **Posted:** Fri Sep 20, 2013 8:37 pm

More like they will not endorse it because they want zero liability if anything goes wrong.....that is what their lawyers will tell them....even if they actually believe the fix to be sound engineering wise.

hucorey · **Joined:** Tue Mar 06, 2012 4:29 am **Posts:** 378

WolverineFW wrote:

More like they will not endorse it because they want zero liability if anything goes wrong.....that is what their lawyers will tell them....even if they actually believe the fix to be sound engineering wise.

True. Now if Jeep had produced many CRD s as Ford did with the 7.3 powerstrokes then I'm sure there would be alot more interest from ARP or performance shops.

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