billmerbach

I have 11/16 inch head bolts

coppercutlass

There is either 7\16ths or half inch. 7\16th go to 85 ft lbs half go to 130.

billmerbach

Are we talking about the heads or the threads cause the heads are 11/16

coppercutlass

Thread diameter . Not head bolt size

billmerbach

I believe. Have half but I'll check before I do my final torque

coppercutlass

Don't guess because the diffrence between. 80 and 120 is 50 that's not a small diffrence. If your engine is pre 73 you have the 7\16 ths bolts.

billmerbach

OK well then I guess I have the 7 16

rustyroger

1/2" to 140 lbft sounds like diesel settings to me.

Roger.

coppercutlass

Rusty roger all my refrences didn't mention 140 for the diesel I kept seeing 130 I saw 142 for the v6 diesel but it had specific instruction to tighten certain bolts to 59 ft lbs and the rest to 142. But the 130 was for an engine with half inch bolts according to the books .

tru-blue 442

Bill, when you go to put your exhaust manifolds back on,
I would go with new bolts. You were lucky none snapped off.
You go torquing on old ones, you will be cussing yourself.
Ask me how I know...

Octania

*sigh*
"head bolt size" is by definition the diameter of the thread [and length] of the head bolt.

BOLT HEAD size perhaps? The size of (the head of) the "head bolt"...

I call it WRENCH SIZE because that makes sense, but in catalogs they often call this measurement, which has NOTHING to do with the torque value for the fastener, and can vary for a given bolt diameter.... "AF"

WTH, you say, is "AF"?
Took me a while to decipher that; other engineers I work with had never heard of it. It is for "Across the Flats". AKA, the size of the wrench or socket that you need to proceed.

It is not uncommon for non-std wrench size to be specified for an application. Think Olds rocker cover and oil pan 1/4" fasteners. The usual tool size for a 1/4" screw is 7/16", but for this low torque application, Olds used a 3/8" AF flanged fastener.

Similarly, the SBO main cap fasteners are typically 7/16" diameter for #1-4 and 1/2" for #5 but ALL of them bear 3/4" AF heads- the std size for the 1/2" fasteners, but larger than the std size for the 7/16" screws. Only one size drive tool needed for all of them.


OK well then I guess I have the 7 16
======================
Find out for sure, don't guess
In my experience with Olds engines, the 7/16" head fasteners use an 11/16" socket or tool, whereas the beastier 1/2" fasteners require a 13/16" tool.

Oh, and if you apply 120 ft-lbs to a 7/16" fastener, you will probably produce the 2-part screw that provides no joy- or clamping force.

PS I took some liberties here with the terms "bolt" and "screw" but they are actually defined differently, even if we USE and REFER TO the parts interchangeably as we wish.

MDchanic

+1. And they're not "specials," either - Regular Grade 8 or Grade 5 bolts are just fine.

- Eric

MDchanic

Thanks, Chris. Great description.

- Eric

billmerbach

Thanks but I'm done at the moment I noticed to me what looked like gap on the intake and I went back and read the directions to realize I read the wrong ones and didn't put the silicon on the gasket....pissed I messed up again but I'm happy I went back and reread things

MDchanic

That's how we all learn. It's annoying, but after a while you get used to it.

(Notice I didn't say, "... you do it less.")

- Eric

billmerbach

My mistakes seem to come more frequently

oldolds88

its called 'sperience.

oldstata

Bill it gets better with knowledge but that is how we learn by making mistakes at least you went back and cought it early

X1000

coppercutlass

Octania yes I said that backwards lol. Moral of my story is you go by the diameter of the threaded portion of the cylinder head bolt.

oldstata

Bill,
What book are you using?
If you are using the manual for your omega that could be the reason torque and sequences are different.

billmerbach

I was using a cutlass book butanother one I had said 80 OK I got a question can I use the hih temp rtv the red stuff on the valley pan that stuff is silicone so it should work right?

oldstata

I am not sure if I am thinking of the right stuff here, but I think the red rtv is water base good for the T stat housing/ water pump

I would use the. " right stuff " it's black and it great

billmerbach

The stuff that was on there was this blue stuff I think I found it

oldcutlass

You did buy a new valley pan gasket?

billmerbach

Of course but the stuff that was in there was dried up and I thought it was for the black gaskets so I used a dab of high temp rtv and then as I was bout to put water in there I basically realized that the stuff they gave me was for the valley pan so I threw my hands up And quit for the day

oldcutlass

Your not the first to do this. The dried out stuff in the tube is just black RTV. Also make sure the little pilot bosses drop into the holes and the gasket lays flat on the heads.

Anyone can take an engine apart, the skill lies in put it back together correctly. There is a difference between ignorance and stupidity. Ignorance is making a mistake without knowing better, stupidity is when you do it again.

billmerbach

Well I did everything correctly except the silicone so I guess I ain't that ignorant

billmerbach

Just picked me up some silicon on eBay so I have something to do next weekend d

oldstata

X2
Not reusable after being torqued down

olds 307 and 403

You can reuse but there is a chance of vacuum leaks, I have had good luck reusing. I use Permatex Aviation sealant around all the ports, both sides except the 4 end water ports. I use RTV both sides on the 4 water ports and tall beads in place of the rubber end seals. If it is 77 and later, you can go 130 on the head bolts. Didn't you put in a 307? Then it is the higher spec. Hopefully you put oil on the threads. It will hold fine though, even at the 80 spec.

billmerbach

I put oil in them but basically I have to buy a new gasket is what you are telling me :/

oldstata

You can re torque the head gasket. I wouldn't reuse the intake valley pan but that's me

billmerbach

dang it I'm bout tired of this screwing up crap its getting old

Seff

You've still gotten much further than if you'd never started, and giving up gives you a 100% certainty of the engine never running. So press on - these are small hurdles.

billmerbach

You're right and I'm not gonna stop here I'm gonna get better and hopefully minimize my mistakes

billmerbach

Do I need the valley. Pan or can I just get gaskets. I know the valley pan is there to keep hot oil from splashing on the intake but is there any other pros to it

BlackGold

Actually, you've got it backwards. The valley pan keeps the hot intake from cooking the oil splash into carbon. The bottom of the intake right under the carb is the exhaust crossover. It allows exhaust gases (1000+ degrees) to warm the floor of the intake to improve cold-weather drivability.

billmerbach

Ok well I ordered a valley pan anyway lol

oldcutlass

That's the spirit. It's principle, man made it, so man can fix it.

oldstata

Bill you are doing great work! just keep hanging in there and don't be afraid to ask questions.