types of wrenches for tough bolts?

[1987cp]

For the O2 sensor: Why not go to AutoZone and rent an O2-sensor socket?

[BerniniCaCO3]

The socket won't fit over the original sensor; there's a metal sheath in the way :-(

And still no luck with that one friggin bolt. *sigh*

[Lincolnmania]

use a 7/8" wrench

[1990LTD]

One of the bolts on my plenum cover is so rounded, it looks like a rivet. Should I be fine cutting it enough so the head of the bolt snaps off? Looking at my spare intake, I don't really think there's any danger of me cutting anything vital

What say you guys? Dremel?

[Lincolnmania]

it's a t20 torx.......beat a t25 into the screw and back it out

[gadget73]

T20 sounds right. usually you want to stick the socket in there and give it a whack to seat it and break the corrosion loose. They come right off then.

[BerniniCaCO3]

alright, got it off! Had a bit of help from a friend too.

I'd badly stripped it, so what it came down to, was hitting with a stone chisel and 3lb hammer to try to shock it loose, then experimenting with mushrooming the bolt and inserting an aluminum spacer into a 13mm socket (it's a 1/2" bolt) to get a tight press fit, and finally, using the chisel to pry up the old starter motor until the top bolt came free.

Rather extreme measures, but that darned bolt was so very far gone...

I'm replacing the bolt with a nice grade 8 that shouldn't round off like that ever again!

[91waggin]

grade 8 ftw.

[gadget73]

no, antiseize ftw.

[BerniniCaCO3]

well, if only ford had thought to use antiseize on the original part!!

Oh, QUESTION: yesterday I just broke another bolt in the engine housing, while doing the valve cover gaskets. I can't be thankful enough: a lefthand drill bit pulled it out in tact (not reusable-- but tapped threads remained a-OK).

Now I replaced that bolt with a 1/4-20, 3/4" long grade 8 bolt from home depot.
The valve cover screws ARE 1/4-20, right?

Anyway, the idea is that the new screw should never break off again.
However, grade 8 bolts are a reasonable alloy that's been hardened and tempered.
Therefore, a drill bit of a reasonable alloy that's been hardened and tempered, won't necessarily be able, any longer, to remove a broken grade 8 bolt!

High strength is lovely, but can it stab you in the back, because when a grade 8 bolt breaks, you'll need cobalt, tungsten carbide, or abrasive/diamond tooling to drill and tap it out again??
OR, a high-strength bolt can possibly strip the threads in a softer housing?

That is to say, was ford just cutting costs, and if one had the money, there'd be no reason not to use grade 8 bolts for every single bolt in your car: or are there very real engineering reasons to go with a softer bolt?

[91waggin]

There may be other reasons, but for the most part, using grade 8 on a lot of shit is just throwing money away because it's overkill.

[1987cp]

1/4-20 = correct. Except for one hole I came across that'd gotten buggered and someone retapped it for 5/16-18.

Also agree mostly on the Grade 8 thing. Lots of factory engine fasteners were Grade 5, like intake and front cover bolts, and on a low-stress fastener like a valvecover bolt (I usually grab not more than 3" or so out on a 1/4" ratchet for that task, unless I really feel like dragging out a torque wrench for a noncritical fastener), you can normally get away with a Grade 2 or even the cruddy hardware-store stainless bolts that have very little tensile strength.

Come to think of it, even some suspension stuff is supplied with Grade 5 fasteners or metric 9.8. I know the toplock nuts I used on my front upper control arm shafts were approximately Grade 5 equivalent ("Class C" IIRC).

My personal favorite valvecover bolts I've seen were ARPs of some description that had nifty little 3/8" heads with integral collars.

[Piece-it pete]

I second gadgets antiseize comment. Unless I want it to seize for safety reasons I use this:

http://www.permatex.com/products/automotive/lubricants/specialty_lubricants/auto_Permatex_Nickel_Anti-Seize_Lubricant.htm

although I see a guy on ebay selling 16 oz cans of the loctite equivilent for small $, seach for loctite 77164.

I used to use copper based but it's so inexpensive for the nickel via ebay now, why not?

Pete