Warning against using ARP L19 rod bolts...

[blykins]

Hmm...I have a set of Oliver rods with L-19 bolts for my new build.  Food for thought.

I'd consider swapping the bolts out. 

I've used many sets of Oliver rods with L19 bolts over the years, but before a couple of years ago, I had never seen any warnings about how you should handle them.  It wasn't on the spec sheet, but if you do some research, you're supposed to wear gloves, not use certain solvents on them, keep them in oil, etc.  For most scenarios, the ARP 2000 bolt will be just as strong, without all the finicky-ness, or you can switch to the ARP Custom Age bolts.

An ARP 2000 bolt is not as strong as a L19.  The Custom age 625+ is stronger than an L-19. Are so many applications that even an ARP 8740 bolt is fine that we forget to consider what is needed for a given application. Without knowing the weight of the rod/piston, stroke, and RPM and calculating the load the bolts will see nobody can say a lesser bolt will be ok.  If the rods are new and have been stored/handled properly I see no reason not to use them.  If you want to go with a different bolt I'd suggest call Oliver and let them recommend what bolt will work for your application.  Whenever possible before changing anything with rod bolts always best to speak to the rod manufacture as the design and material of the rod go hand in hand with the rod bolt.  Most connecting rod manufactures custom spec their rod bolts.

Just remember changing to a different bolt may require resizing the rod big end.  Really should check the big end with the bolts properly stretched regardless.

In my situation, the engine had come back for freshening and I replaced all of the rod bolts with brand new ones.  They came right out of the package from Oliver, got lubed up with CMD, then cycled to check stretch.  They were brand spankin new bolts and my guess is that one fractured/failed, which caused the other to fail because it couldn't handle the load by itself. 

In my buddy's situation, they called the rod manufacturer and the rod manufacturer told them to just switch to ARP 2000 bolts.  The rods didn't need resizing, so they went with it. 

I do agree that Phil should call Oliver and ask their opinion on a different bolt (they do have different options), that's why I used general terms such as, "I'd consider swapping them" and "For most scenarios..."   

In a lot of cases, the ARP 2000 bolt may be a solid option.  I'm starting a couple builds that will use Jay's heads and one of them is using a set of Molnar Power Adder rods.  They have ARP 2000 bolts. 

He will just have to call Oliver and see what they suggest, but I would firmly urge him (or anyone) to call and inquire.  This is the second instance of an L19 bolt failing close to home and a quick Google search will show many more.   You just don't see/hear that from the other bolts. 

[blykins]

Phil, I got out the torque sheet for Oliver rods and they offer 3 different bolts with their rods:  L19, ARP 2000, and the 625 bolt.   Since they offer the rods with all of those bolts, it would be an easy phone call to see what would be needed with the other two. 

What stinks is that their instruction sheet says to clean all parts thoroughly before lubing the bolts up and checking stretch.   It certainly doesn't tell you how to handle the L19 bolts and from reading some other sources, the L19 bolt doesn't like some types of solvents. 

[philminotti]

Yeah, I did the research when I bought the rods a while ago... It's something that crossed my mind.  I was aware of the handling precautions... That being said, if a rod bolt needs that much TLC to avoid potentially catastrophic failure, philosophically that's just a bit weird, in my opinion.  Good grief, this isn't a Space X Raptor engine for chrissakes. I wasn't planning on doing my build in a sealed, positive pressure clean room, surrounded by HEPA filters, bathed in UV light while wearing a bunny suit😂

[blykins]

Yeah, I did the research when I bought the rods a while ago... It's something that crossed my mind.  I was aware of the handling precautions... That being said, if a rod bolt needs that much TLC to avoid potentially catastrophic failure, philosophically that's just a bit weird, in my opinion.  Good grief, this isn't a Space X Raptor engine for chrissakes. I wasn't planning on doing my build in a sealed, positive pressure clean room, surrounded by HEPA filters, bathed in UV light while wearing a bunny suit😂

Hey, let’s be serious. There’s nothing at all wrong with wearing a bunny suit while working on engines.

[67xr7cat]

It is totally possible had some bad bolts. Was some ARP 2000 bolts guys were saying broke too. For sure even an ARP 8740 is more than enough for most applications and that may surprise some. Really comes down to application, how much margin of error, and comfort level.

Can add to the list moisture for the L-19. Really to a much lesser extent the ARP 2000 and ARP 8740 can have same issue. Really have go to the Custom Age 625+ to be fully rid of it. Of course that is a better bolt all around just expensive.

I've always run the bolts in and out and torqued then 3-4 times. Measure the length before and after. I know with the new lube say don't have to, but cannot hurt and maybe put a few cycles on them if have a bad bolt the stretch will change.

Then is the lost art of feel. Long time ago we had a Custom age bolt that when tightened felt different. That bolt got replaced.

I just cannot get on the L19 "look at it sideways
it will explode" bandwagon. Yes need to wear gloves and keep them oiled something should do anyway, but I'd think if was really that bad ARP would have stopped selling it, but each should do what they are comfortable with.

[frnkeore]

This is kinda odd to me. Even with the few instances described here, I'm sure there are more. Are people not relating this issue to ARP?

If they are telling ARP, I would think ARP would ask for all the bolts in those engines back, to research what is happening.

You could also research it yourself by sending them to a metallurgist and have them tested or if you have access to Xray and a hardness tester, you could do some of it. Inclusions in the metal and out of spec steel or HT (to hard) could cause this but, we won't know until they can be tested, after the fact.

Seems to important to me, that ARP would turn a blind eye to this!

[67xr7cat]

Yes good point Frank would think first thing be call ARP or the rod mfg. when you have a bolt failure. Guess is engine builders get so used to hi performance aftermarket parts not fitting, always needing some kind of work or massaging.

[Yellow Truck]

Yeah, I did the research when I bought the rods a while ago... It's something that crossed my mind.  I was aware of the handling precautions... That being said, if a rod bolt needs that much TLC to avoid potentially catastrophic failure, philosophically that's just a bit weird, in my opinion.  Good grief, this isn't a Space X Raptor engine for chrissakes. I wasn't planning on doing my build in a sealed, positive pressure clean room, surrounded by HEPA filters, bathed in UV light while wearing a bunny suit😂

Hey, let’s be serious. There’s nothing at all wrong with wearing a bunny suit while working on engines.

Seriously, we need pictures.

[1968galaxie]

One must also remember that there are many ARP bolt forgeries (fake parts) available.
Just like aircraft AN parts.
There are many cases where fake (Chinese copies) hardware is sold into the US market.

[blykins]

I reported it to Oliver when it happened and my buddy also reported his failure to the rod manufacturer that he was using.   I'm not sure if they contacted ARP or not, but in my case, the rod bolts had Oliver imprinted on the bolt heads, so I thought I should contact Oliver. 

[67xr7cat]

I reported it to Oliver when it happened and my buddy also reported his failure to the rod manufacturer that he was using.   I'm not sure if they contacted ARP or not, but in my case, the rod bolts had Oliver imprinted on the bolt heads, so I thought I should contact Oliver.

Good so what did they say? Were the bolts sent back for analysis? Am sure they are the real deal. Considering how many rod bolts they make is bound to be a few bad ones.  Sure nobody want to hear that, but that is why have to pay attention to the details. As Jay mentioned about bad heat treat can ruin your day. Bunny suit or not  I'd just sure rather find out while still on the bench then at 7,000 RPM!

[blykins]

I reported it to Oliver when it happened and my buddy also reported his failure to the rod manufacturer that he was using.   I'm not sure if they contacted ARP or not, but in my case, the rod bolts had Oliver imprinted on the bolt heads, so I thought I should contact Oliver.

Good so what did they say? Were the bolts sent back for analysis? Am sure they are the real deal. Considering how many rod bolts they make is bound to be a few bad ones.  Sure nobody want to hear that, but that is why have to pay attention to the details. As Jay mentioned about bad heat treat can ruin your day. Bunny suit or not  I'd just sure rather find out while still on the bench then at 7,000 RPM!

As I mentioned in the very first post, they “had never heard of that” and were unwilling to help. 

Regardless, with the countless numbers of rods that have went through here with ARP 8740 and 2000 bolts with never an issue, here’s two instances of L19 bolts failing in the past 2 years.  Take it for what it’s worth, it was just meant to be a warning. 

[chilly460]

I’m sure it’s not a black/white issue for when L19s would be “needed” or suggested, but what general type of RPM or application would they be needed?  6500rpm heavy piston, 7000 truck puller, 7500rpm bracket racer…or something more radical?  Trying to understand if any hand wringing trying to decide to take the risk of running them is more an academic exercise than practical application in an FE?

[67xr7cat]

I reported it to Oliver when it happened and my buddy also reported his failure to the rod manufacturer that he was using.   I'm not sure if they contacted ARP or not, but in my case, the rod bolts had Oliver imprinted on the bolt heads, so I thought I should contact Oliver.

Good so what did they say? Were the bolts sent back for analysis? Am sure they are the real deal. Considering how many rod bolts they make is bound to be a few bad ones.  Sure nobody want to hear that, but that is why have to pay attention to the details. As Jay mentioned about bad heat treat can ruin your day. Bunny suit or not  I'd just sure rather find out while still on the bench then at 7,000 RPM!

As I mentioned in the very first post, they “had never heard of that” and were unwilling to help. 

Regardless, with the countless numbers of rods that have went through here with ARP 8740 and 2000 bolts with never an issue, here’s two instances of L19 bolts failing in the past 2 years.  Take it for what it’s worth, it was just meant to be a warning.

Well in the  "take it for what it is worth category" several years ago some guys (engine builders) were complaining about ARP 2000 bolts breaking. Kinda went the same way. You are certainly not the first to raise the issue of the special precautions for the L-19 bolts. I've never had a bad one or first hand known of a bad one. I know of one instance of a custom age 625+ bolt was bad.  Now I never warned anyone not to use them because of it, but guess maybe I should have. Personally if the application warranted an L-19 rod bolt I'd not be afraid to use it.  To me measure them, cycle them several times, measure them again, and use proper technique and handling regardless of rod bolt.

Will say you would think Oliver would at least want to see the bolts or send you another set. 

[67xr7cat]

I’m sure it’s not a black/white issue for when L19s would be “needed” or suggested, but what general type of RPM or application would they be needed?  6500rpm heavy piston, 7000 truck puller, 7500rpm bracket racer…or something more radical?  Trying to understand if any hand wringing trying to decide to take the risk of running them is more an academic exercise than practical application in an FE?

Is an excellent question. An 8740 and 2000 bolt are about the same strength, just the 2000 has about double the fatigue rating. For a lot of uses a 8740 is fine.  A 2000 is a good insurance policy.  When you start getting into higher RPM and heavy rod/piston weight need to calculate the load that the rod bolt will see and it has to be less than its clamp load. Other thing that enters into it is fatigue life.  A better bolt tends to live longer even if a lesser bolt can take the loading trying to pull it apart.

When you get into endurance racing you start to see better rods and bolts being used.  Shop I worked for in a different life built good number of dirt modified and outlaw engines.  Fairly normal for them back then were Custom age 625+ or WSB rod bolts.  Remember a Prostock BBF had s Bryant billet crank and Oliver rods totally melted the rod bearing. Had the rods and bolts not been of that high quality am sure it would have broke the rod which it did not. The crank polished up. Can say the heat treat was real good on that one! 

Sorry not a straight forward answer, but when racing gets serious so do the parts, especially if the goal is to win.  For most street/strip and bracket racers a scat rod and ARP 2000 bolts more than enough.