HappyAdventure

I have been pouring through the forums getting ready to start a head gasket and just seem to run into more questions about the head bolts, whether or not they are torque to yield, and what bolts to buy.

The dealership bolts are horribly expensive, so I am hoping to buy something cheaper. Just on RockAuto they have four different sets - Fel-Pro, Beck and Arnley, Rock, and Victor Reinz - without any real info on the bolts. Engnbldr.com has a set that is not TTY but high quality bolts and only 39 bucks. Anyone have any new info on the reliability of head gaskets with different bolts or advise on which set to buy?

I was also looking at EB's much re-posted HG torquing instructions:
"*Quite a discussion. We always replace the head bolts on the 3VZE, mostly because of early on we had two cases of breaking them. This spoils a day quickly...

*Ever notice it is nearly always either the last one or the next to last one?...*LOL**

I personally won't make the studs, I do not own the equipment to roll the threads during the forming process. Sure, I could set up and cut the threads, this is much weaker than a formed and rolled out piece. *More work, too and I'm lazy.......All it takes is one little stress riser and the stud can break.

Usually breakage with bolts is due to the threads creating resistance, they stop turning. The same can happen with a stud if the nut end threads are not completely free and lubed. Once they stop slipping as they are torqued, you are now twisting the shaft of the piece. I have had a couple of cases of folks breaking brand new bolts, this is the cause of that.

If the shaft of the fastner is actually twisted rather than tightened into the block, it is not creating clamping force at all, even though the torque wrench may read accurate load.

Yep, it can break. So before we even think of going to maximum torque, we clean the threads in the block with a chaser, (NOT a tap)..Then we oil the threads and spin the bolt all the way in and out with our fingers. This assures they are clean and lubed.

Then we pull them to 50%, all of them. ... back off 1/4 turn and repeat, note each time it will turn a tad more before 50% is reached. This is because the threads are bedding in. We do this 5 times, then we go to 75%, then to 100%, all done. We do this with ALL new fastners...it assures a more even clamping force, inconsistant clamping force is the number 2 cause of early head gasket failure..(heat is number one)

It takes some time, sure, but it takes less time than pulling the head back off...Hope this helps.....*EB"

How are these instructions usually adapted to the 33lbs, 1/4 turn, 1/4 turn FSM instructions? Go to 33lbs then go through 50% of the 1/2 turn, back to 33lbs then to 75% of the half turn, etc? Does this defeat the purpose of the (mythical? not mentioned in the FSM) TTY bolts?

Also, anyone know the size of the chaser for the head bolt threads?

Thanks!

sb5walker

First, I would only use TTY bolts, which have a reduced shaft diameter. They will stretch, offering a big advantage in keeping more uniform clamping force with aluminum heads, since the thermal expansion rate for aluminum is considerably more than for iron. And for TTY bolts, I would definitely use the fsm procedures for torquing. The torque method you quoted sounds like it's for non-stretching, roll-shaft bolts.

I was under the impression the Rock bolts (which I think are what Ted sells) were TTY - are you sure they're not? You can usually tell because you can see a reduction in the shaft diameter a little below the head.

Of the brands mentioned, I would probably choose either the Beck/Arnley's which used to be very high quality Japanese-made (not sure if they still are, tho), or the Victor Reinz, which are a good German brand used as OEM on Porsches, I believe. Or, if you want to be sure, you can get the oem bolts from one of the dealers who offer online discounts (see this post for a list of them).

This is a pretty good article from Victor Reinz that may be worth a look:
http://www.gomog.com/allmorgan/HeadBoltTorquing.pdf

HappyAdventure

I am not sure if Ted sells the Rock bolts, but I emailed him about the bolts and he said "Not exactly, they do torque the same way as the stock bolts but they are 10.9 grade and thus reusable." Sounds like they are not TTY.

Thanks for the link to the Victor Reinz article.

some drunk guy

Engnblder.com has the headbolts $39 plus $10 shipping. yes 33ft pounds of torque, in the FSM sequence, then 90* same sequence, + 90* same sequence.

HappyAdventure

Found the answer to the torque question about EB's torquing method:

The 3VZE is different in that the first spec is 33# I believe. So we typically install in sequence to 33#, back off 1/4 turn and reset them to 33#. Then 1/4 turn all, then 1/4 turn again (90 degrees).

sb5walker

That sounds reasonable. You won't have stretched them at 33 ft lbs. It's very important with TTY bolts that they not be loosened after they've been stretched.

CarSick?

Any idea what size thread chaser?

YotaWoRx

11X1.25mm

CarSick?

Thanks yotaworx...im about to head to autozone and see what i can find...maybe they rent out a set

CarSick?

So from what I've seen thread chasers are kinda pricey...would using a tap work if I'm carful? What size tap would I need? Also on the head bolts I planned on thread locker and following the sequence in 20ftlb increments up to 60 ...any thoughts?

millball

Torque to yield type bolts are designed to apply a specific elastic clamping load to the head/block joint. Most usually used on aluminum head/iron block combos in conjunction with graphite based gaskets to allow some slip between the surfaces. This is required to give the longest possible service life in spite of the grossly different coeficients of expansion of aluminum and iron.
Stick with the Program outlined in the FSM. Never use these bolts twice. Once tightened they are done.
I chase threads with a regular tap all the time, no problems.

CarSick?

I have new head bolts but I don't think they're tty...

millball

What is their origin?

CarSick?

They're stamped 10.8 on the head. Came with a head gasket set off ebay . I was able to rent a thread restorer tool set from autozone but it doesn't have m11 . Just m10 then m12 . It does have standard size chasers to ....would
D one of the standard size thread chasers work ?

millball

10.8 is an ISO Metric bolt strength designator. It has nothing to do with bolt size or thread specs.
Nothing but the correct size tap or thread chaser will do for the block thread cleaning and those threads must certainly be cleaned if you want a properly tightened head gasket job that can be expected to hold up.
You should be able to buy the correct tap for $10 or so.
YotaWoRx said that the size is 11x1.25, I don't know for sure.
Take a new bolt with you and you will be able to get the correct tap for certain.
Follow the FSM tightening regime.

YotaWoRx

Yea M11X1.25mm is the size. I had to buy one on amazon to chase the threads on my motor. It was like 10 bucks or so. Shipped from china

11mm X 1.25 Metric HSS Right Hand Thread Tap M11 X 1.25mm Pitch
http://amzn.com/B0084C5ZOM

CarSick?

Torqued in Sequence to 33ftlb then added 90* in sequence then another 90* (33ftlbs plus 180* turn) . I had a hard time gettingnthat last 90* ....I got maybe half way through the last 90* pull on every bolt. Now i just need to track down some banjo bolt crush washers so i can finish this thing up.