TTY head bolts - more than you might want to know.

[theman53]

That's like $130 for the hardware that you still consider single use.  I'd just buy the stock bolts or the ARP studs. and not mess with an experiment that costs 10 times what the stock bolts cost.

I thought so too, but it is 7....ish per pack of 5, so it is only around 20.00. Which for import is still high as can be. I could sell the American made or SPS Unbrako for close to that now.

[TylerDurden]

From Bill McKnight, Director of Training for MAHLE Clevite:

" Unless specified otherwise, 30W motor oil is the standard lubricant for automotive fasteners. If we want to achieve loads similar to the OEMs. we need to lubricate our fasteners with 30W oil. Don’t forget that underhead and thread friction both need to be controlled, so lubricate both areas. In the case of head bolts going into the water jacket, the sealer on the threads will provide the lubrication needed, so just apply oil to the underside of the head of the bolt. Super lubricants may actually get you in trouble by relieving too much friction, leading to over-tightening."

http://www.enginebuildermag.com/Article/2343/threaded_fasteners_torquetoyield_and_torquetoangle.aspx

[TylerDurden]

From Fel-Pro Torque Guide:

"Lightly coat bolt threads and the underside of the bolt heads with motor oil. When they enter the water jackets of an engine, bolt threads should be coated with a non-hardening automotive sealer to prevent leakage."

http://www.felpro-only.com/tec_notes/Fel-Pro_Torque-Guide.pdf

[JFettig]

Do whatever you want man. Its your motor.

If you look through the bentley, it says to oil certain bolts... it doesn't specify for others, probably a reason for that

[745 turbogreasel]

The reason being they mistakenly assume you know it?
My 84 factory manual is pretty specific:

Tightening torques
Apply to lightly oiled nuts and bolts.
Degreased (washed) parts must be oiled prior to assembly.
Cylinder head--tighten in stages
sequence[pic]
Tighten cylinder head bolts in stages
Remove oil and dirt from bolt holes.  Oil and dirt left in holes will reduce  the pressure on cylinder head gasket.

Bolt threads and washers must however be oiled, otherwise frictional forces will be too large.

Use new bolts.  The washers need not be replaced.

Tighten in six stages:
stage 1=30ft/lbs.
stage 2=44ft/lbs.
stage 3=55ft/lbs.
stage 4=tighten 180* Note this should be in one movement without stopping.
stage 5=Run engine till oil temperature is at least 112F.
stage 6=tighten 90* Note this should be in one movement without stopping.

Retorquing of cylinder head bolts
Retorque after 600-1200 miles.  The engine should be cold or almost cold.

Tighen each bolt separately and in correct sequence(see pic).

Tighten bolt 90* Note this should be in one movement without stopping.

Bolts should not be slackened first.

Emphasis is all as per the book. I left out the metric specs, and pic, cause I type slow.
book 760-03, section 2, Page 40.


There is a revision for 85+, bolts have captive washers, do not reuse.

[TylerDurden]

The 1980 and 1981 editions of Bentley spec using anti-seize on headbolt threads and washers, plus changing from hex to 12pt bolts.

[8v-of-fury]

As a mechanical engineer who designs bolted connections on a regular basis, I have a little bit of an idea whats going on here

I would think that because this man has a degree and literal hands on experience with the exact matter at hand, maybe he does actually know what he is talking about?

Just because it is written in the "Bentley" does not mean it is written as matter-of-fact, or that it was even right in the first place when published.

[ORCoaster]

Just because it is written in the "Bentley" does not mean it is written as matter-of-fact, or that it was even right in the first place when published.

And how many misstated things do we already know about in the "Bentley"?  Plenty if I can think about it a bit.  Not all is as it should be.  Publishers do make mistakes.  Like we don't?

[shorttimer]

To heck with all the bickering about bolts. Even with my paltry income, I find the ARP bolts to be a good value. I've never blown a head gasket, but i don't want to take any chances after all the work I've done. I can easily go without movies, eating out & other consumables to have good hard parts.

[burn_your_money]

Considering how many people have oiled their bolts and had success, and how many have not oiled them and had success I think it's safe to say that in this application it doesn't really matter.

[air-cooled or diesel]

most of the head bolts i get have anti-seize with them (in seperate packet) so i use it, (not the anti-seize that comes w/bolts either).
might i point out using OIL on head bolts can cause you to crack your block, and i find anti-seize to be better.
i saw at least 1 post of using brake clean and compressed air.++.

[R.O.R-2.0]

most of the head bolts i get have anti-seize with them (in seperate packet) so i use it, (not the anti-seize that comes w/bolts either).
might i point out using OIL on head bolts can cause you to crack your block, and i find anti-seize to be better.
i saw at least 1 post of using brake clean and compressed air.++.

its when you leave a PUDDLE of oil in a hole.. like to the top of the hole, and the bolt comes down on top.. hydraulic pressure pushes the oil down, and the only place it has to go, is thru the block..

[air-cooled or diesel]

not so BIG of a puddle is necessary to push thru block, theres not alot of space between bottom of bolt and block, and bolt seals at block if even 1 thread up the bolt, you wont need a lot of LIQUID to do it.
in any case the main thing is cleaning holes w/brake clean everytime. And make sure all brake clean is dry too.

[TylerDurden]

New bolt length = 110.4mm (Tip to washer)

Block-Hole depth = 43.5mm
Head-hole depth = 78.8
Gasket = 1mm
Combined hole depth = 123.3mm
Remaining threads in block after threading head and bolts = 11mm (corrected from 13mm)


Bolt threads below head/gasket = 32mm
Head recess before threads begin = 13mm
Thread engaged during fastening = 19mm

[745 turbogreasel]

Also, the bolt is stretched one full turn or 1.75MM, leaving 9.25MM