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Fri Oct 24, 2008 9:59 am

I'm installing the head studs and I thought I would put 20 pounds on them. After all, the heads will get torqued that far...might as well see if the studs will hold. I have had three savers spin on the first four I tried. The second four, I only put in wrench-tight and they didn't spin. I'm thinking about mocking a head up and torquing them with the head on to see if that changes anything.

I mentioned this to Darren (got a new case with 8mm studs and savers) and he wanted me to spin them through the case on the inside and then reinstall with Loctite. It sounded good, but I didn't exactly do that. I dripped some green Loctite (the assembed-parts one) in there and they are still spinning.

What do I do now? Should I try installing the head or spin the savers out first? The case is split, btw.

Fri Oct 24, 2008 11:23 am

You should spin the savers out. Then clean the area and savers with brake cleaner. And then put the Loctite. I'm thinking the problem you are having is that there may be oil or something that is not letting the set up.

Fri Oct 24, 2008 8:22 pm

The Green loctie is not going to cut it , use some blue, or red.

Fri Oct 24, 2008 8:53 pm

Sigurd wrote: I'm installing the head studs and I thought I would put 20 pounds on them. After all, the heads will get torqued that far...might as well see if the studs will hold. I have had three savers spin on the first four I tried. The second four, I only put in wrench-tight and they didn't spin. I'm thinking about mocking a head up and torquing them with the head on to see if that changes anything.

I mentioned this to Darren (got a new case with 8mm studs and savers) and he wanted me to spin them through the case on the inside and then reinstall with Loctite. It sounded good, but I didn't exactly do that. I dripped some green Loctite (the assembed-parts one) in there and they are still spinning.

What do I do now? Should I try installing the head or spin the savers out first? The case is split, btw.

You answered your own question follow the instruction that were given to you and that will solve your problem

Sat Oct 25, 2008 12:38 am

Darren Gurrola wrote: The Green loctie is not going to cut it , use some blue, or red.
Begging your pardon, but there are a number of different Green Loctite formulations including one very low strength Loctite formulation designed to hold adjustment screws in place.

Green Loctite #620 retaining compound is extremely strong and will maintain it's strength longer that most other Loctite formulations when used at higher temperatures, and will outhold high strength Loctite Red formulations at higher temperatures. You can't just specify red, blue, or green. You need to specify the Loctite formulation number.

Cleaning the threads before the application of Loctite is critical! If the inserts are plated, you may need to apply Loctitie Primer. At least one of the surfaces must be an active metal that will initiate the curing reaction. Magnesium, Aluminum, Stainless steel, black oxide, zinc, cadmium, titainium, anodized aluminum, silver and gold are not active metals and generally require a Loctite primer. Bare steel, iron, nickel, copper and brass are active metals and will activate Loctite by themselves. Loctite primer will speed up the cure time on all metals.

Download this Loctite information on primers.
http://www.henkelna.com:80/us/content_data/lt4856_primers_sell_sheet.pdf

Scott Novak

Sat Oct 25, 2008 1:07 am

Well, I guess I have some things to try tomorrow. I don't remember the formulation number, but the green I used was the really-high-strength one that you apply to assembled parts, not the set screw one.

What's a good torque to set the studs to? Once I get the savers set, that is.

Sat Oct 25, 2008 1:22 am

Also keep in mind that the cure time of the Loctite can vary greatly. If the Loctite is old it could take a couple of days to set up. If there is any trace of oil it can take longer to set up. Fresh Loctite #620 on a brass oil return fitting, when used with Loctite primer, can start setting up so fast that you can barely get the fitting turned in the case before the Loctite sets up.

if you have a junk magnesium case, Loctite a bolt and screw it in the case and see how long it takes to setup and cure.

Scott Novak

Sat Oct 25, 2008 8:32 am

FYI, this is Loctite 290 that I'm using.

Sat Oct 25, 2008 8:39 am

BTW your case savers never see 20ft-lbs of rotational torque, the stud pulls on the saver, not twist them. You created this mess yourself, it was just a bad idea or someone misinformed you. :x
Either way thoroughly clean the thread on the savers and case with brake clean, reinstall with red loctite and Allow to sit overnight to ensure complete curing.

Good luck with it.

Sat Oct 25, 2008 9:00 am

Scott, no pardon to beeged here. I gave my professinal opion on this issue, after thousands of engines being built at my shop, you know what works and what will not work, throw the green loctie in the trash.

Sat Oct 25, 2008 9:55 am

Alright, I'm chalking this up to be a learning experience. I'm going with the "seemed like a good idea at the time" :oops:. Five savers have come back out smoothly. One stayed put. And two studs snapped. Needless to say, I'm stepping away from this for awhile before I F anything else up.

My thinking was that since I put the heads at 20 pounds, shouldn't the studs be at 20 pounds as well? Or is the 20 pounds created by the load of the head nut contacting the head? So then I should be just setting the studs at wrench-tight instead of a specified value? I feel like I'm making this harder than it should be. What am I doing wrong here?

I don't doubt you guys at all. That's why I'm trying to sort this out. Like, I said, I'm stepping away from it for a little bit. I guess I need to find out the hard way sometimes :?.

Sat Oct 25, 2008 11:23 am

Darren Gurrola wrote: Scott, no pardon to beeged here. I gave my professinal opion on this issue, after thousands of engines being built at my shop, you know what works and what will not work, throw the green loctie in the trash.
Which of these 11 Green Loctite formulas did you use that were so bad?

Loctite 290, 294, 603, 609, 620, 635, 640, 648, 668, 675, or 680?

What did you clean the threads with before applying the Loctite?

Did you use a Loctite Primer? If so, did you use Primer N or Primer T?

Scott Novak

Sat Oct 25, 2008 11:56 am

Scott, do you even know who you're talking to here?
Everyone knows you can talk people stupid, can't you just let the man be? He knows what works for him, that should be good enough.

Sat Oct 25, 2008 12:17 pm

Miniman,

Stating that Green Loctite is bad doesn't mean a damned thing, as the are at least 11 different Green Loctite formulations with drastically different characteristics.

Some Green Loctite formulations DO NOT hold up when in contact with motor oil!!! Others weaken when used at higher temperatures.

The use of a primer can have a huge effect on curing time and strength. That can be very important if the engine is put into service before the Loctite has cured.

Loctite is application specific. The formulation that works best on a gland nut may not be best elsewhere on the engine.

So yeah, if someone is going to make a blanket statement that Green Loctite is bad, I want that statement qualified, and I want to know if the Loctite was used properly before I put any stock in what that person has to say.

Gene Berg claimed that Green Loctite was good in certain applications. But that was also a meaningless statement as he never stated WHICH green formulation to use. Of course he would sell the green Loctite to you with a Berg part number.

Scott Novak

Sat Oct 25, 2008 12:55 pm

Sigurd, are you actually twisting the STUDs to 20 ftlbs? Torquing the NUT on the HEAD to 20 ft lbs is one thing.. locking a nut on the stud and twisting to 20 ftlbs is a big mistake. Please clarify.

Sat Oct 25, 2008 1:01 pm

mharney wrote: Sigurd, are you actually twisting the STUDs to 20 ftlbs? Torquing the NUT on the HEAD to 20 ft lbs is one thing.. locking a nut on the stud and twisting to 20 ftlbs is a big mistake. Please clarify.

That is what I got from his post

Sat Oct 25, 2008 1:37 pm

mharney wrote: Sigurd, are you actually twisting the STUDs to 20 ftlbs? Torquing the NUT on the HEAD to 20 ft lbs is one thing.. locking a nut on the stud and twisting to 20 ftlbs is a big mistake. Please clarify.

Oh yeah, that's exactly what I did. :oops:. So I guess that's probably why the two studs snapped at 22 pounds, huh? Yikes. Ok, well, I'm letting this be a $50 mistake (new studs).

I didn't touch the 3/4 case half at all yet, and I'm not going to either. I'm going to lock the savers in the 1/2 half with the red Loctite I have and be done with it.

Sat Oct 25, 2008 1:59 pm

The studs do not get all that torsion when you are tightening the heads down. They get the resulting load along their axis and a portion of that torque due to friction, but not nearly that much..

I never do more than just a mild tightening of them by hand. a few inch pounds, into the savers. They'll get the rest of what they need when you torque the heads down. The main thing is to make sure they are threaded in all the way for max thread engagement.

Ok guys, back to your regularly scheduled programming. lol

Scott, did you.... cuss? :shock:

Sat Oct 25, 2008 2:22 pm

mharney wrote: The studs do not get all that torsion when you are tightening the heads down. They get the resulting load along their axis and a portion of that torque due to friction, but not nearly that much..

I never do more than just a mild tightening of them by hand. a few inch pounds, into the savers. They'll get the rest of what they need when you torque the heads down. The main thing is to make sure they are threaded in all the way for max thread engagement.

Ok guys, back to your regularly scheduled programming. lol

Scott, did you.... cuss? :shock:

Thanks, Mark. I really appreciate you clearing that up.

Sat Oct 25, 2008 3:35 pm

mharney wrote: Scott, did you.... cuss? :shock:

No dinner, young man.