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Practicing Infidel
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15,299 Posts
Discussion Starter #1
Hi all

Just torquing down my TTY head bolts on my 87+ up heads onto the 87 + block.

Did the stitch twice thing from 35lbs to 55lbs and then, for the third and final torque, Haynes said twist the torque wrench past by 90 degrees.

Seemed a little unscientific to me, with me having a torque wrench in my hands already.

These are the backwards compatible "torque to yield" or "flanged bolts" ( I busted one of my on removal and several were bent, so I bought new bolts).

Looking at the pre-TTY bolt specs, it said 68-72lbs as the final torque spec. I decided to dial in 72lbs and watch how many degrees the torque wrench got to before it hit 72 lbs.

I got probably 50-60 degrees and it went "click" at the dialed in 72 lbs.

I'm kinda wondering if that'll do or should I try for more torque to attain that 90 degree twist.

This isn't a hi-po application and I don't have high compression or aluminum heads or an O-ringed block..........what say the experts ?

I'm goin' back out to clean and paint the valve covers, re-assemble the lower intake's stuff, etc.

I'll come back in for your rulings and opinions in a while, thanks in advance

Sixlitre


BTW

I put my shorty headers on the heads and then put the heads on the block and danged if it didn't werk jes fine !:toothless
 

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my bko ate my money
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2,319 Posts
:shrug i did what the head gasket instructions said, haynes was looking real shady
 

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Satyr of the Midwest
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17,738 Posts
I would consult the head gasket manufacturer, as that's what the bolt torque is really applying force against.
 

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Practicing Infidel
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15,299 Posts
Discussion Starter #4
I'm technically "at" the 72lbs

recommended by the factory.

The fly in the ointment (or mayonnaise and CheezeWhiz on the keyboard, damn this is a messy sandwich) is that the torque to yield bolts are in the equation too and they have to be satisfied as well.

Apparently 90 degrees past 55lbs and they will tighten down no mo', regardless of turning past that.

I don't want to crush the sheeeeeet out of the head gasket, now that I'm already at 72lbs, the high side of 68-72 recommended pounds.

What happens if you don't take TTY bolts to their limit ? Do they back out ?

Sixlitre
 

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1,573 Posts
TTY bolts are torqued more than an equivalent standard bolt in the same diameter. Torque to yield bolts are just that- you torque them until they stretch and reach their yield stress where they transition from elastic to plastic deformation. At this point they provide the most consistent clamping force as they are all tightened the same amount according to the bolt themselves and not some nominal external torque value.

If a TTY bolt isn't torqued to yield, yes it will try to back out. Just like a normal bolt that isn't properly torqued.

Follow factory procedures for TTY fasteners (92 and up 302's IIRC) - do not use non-TTY specs or they will be under tightened. With no other information, I'd follow Haynes. While their 90* may seem unscientific, using a proper TTY wrench with a built in angle gauge is even more accurate than any torque wrench.
 

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Satyr of the Midwest
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17,738 Posts
They'll still be in their elastic region, could stretch further, and/or would not keep the correct tension (force) between the head and the block. Usually with TTY bolts you can 'feel' when it's reached the plastic phase, as if it gets much harder to turn at a certain point. At least that's been my consistent experience with them.

Damn, someone types faster than me. :toothless
 

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Practicing Infidel
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15,299 Posts
Discussion Starter #7
They'll still be in their elastic region, could stretch further, and/or would not keep the correct tension (force) between the head and the block. Usually with TTY bolts you can 'feel' when it's reached the plastic phase, as if it gets much harder to turn at a certain point. At least that's been my consistent experience with them.

Damn, someone types faster than me. :toothless
Thanks Sig & Hoxviii

I went back and completed the 90 degree thing and a couple of them burped or screamed when I reached 90 degrees.

That much is done and the pushrods are in and rockers are finger tight. I'm used to rocker shafts with all my Mopars and we just torque to 30 lbs and call it good.

Any tips on tightening the rocker bolts ?

Thanks

Sixlitre


p.s./
Got the Y-pipe bolted onto the shorties today too ! Gonna rebuild the injectors tomorrow or the next day I hope
 

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bolt on pedestal type rockers, right?

If so, it's just a torque down exercise. If you did any head work it's good form to bring the cylinder you're tightening up to TDC before tightening. This lets you make sure you're not bottoming a lifter and starting to open the valve through visual inspection. There is a way to bring up one cylinder and tighten valves on several cylinders, but i don't know the order for a 302. Old factory service manuals covered it back when the valves actually had to be adjusted.
 

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Practicing Infidel
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15,299 Posts
Discussion Starter #9
bolt on pedestal type rockers, right?

If so, it's just a torque down exercise. If you did any head work it's good form to bring the cylinder you're tightening up to TDC before tightening. This lets you make sure you're not bottoming a lifter and starting to open the valve through visual inspection. There is a way to bring up one cylinder and tighten valves on several cylinders, but i don't know the order for a 302. Old factory service manuals covered it back when the valves actually had to be adjusted.
Thanks Hoxviii

Borrowed my neighbour's small torque wrench and got her done. Mine only starts at 35 ft/lbs. Luckily 70% of them were on the back of the cam lobe, where it was. After that I just rotated two more times and got all the rocker arms torqued in properly.

Got the lower intake on no troubles either (even with the dist in and unmoved:toothless). Can't believe FelPro would provide cork gaskets for the front and rear of the intake:doh0715:. Of course I just ran a big, fat bead of Permatex Ultra Copper instead.

Installed the T-stat into the intake, on the bench this time:thumbup Realized the dist's TFI was interfering with the intake install (when the dist is left in the engine:toothless), so I went to take it off.

Couldn't believe that the Ford tech, I thought so much of two Springs ago, had only installed one screw and it wasn't a 5.5mm bolt, it was a slot headed screw:shocked:madder

What a Chev drivin' neophyte ! Anyway I used two alan headed socket screws and they worked GREAT, when I re-installed the TFI after the lower intake was on.



Got the PermaDryPlus valve cover gaskets re-cleaned and torqued them (and the valve covers) into place.

Got the air crossover pipe bolted up to the back of the heads too. Lots left to do and likely won't get a chance tomorrow as I'm driving someone to the doctor in a village East of here, then downtown into the city on another mission of mercy and finally hope to be chasing the white ball with some buddies near days end.

That's Saturday shot ! It's sposed' to rain Sunday and Monday so that ought to keep me in the garage.

That's for all the help all

Sixlitre
 

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Practicing Infidel
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15,299 Posts
Discussion Starter #10
Got her all back together and it leaked fuel like a sieve

Had to de-rust the fuel rail sockets and grease a second set of O-rings and now it's running great again !:thumbup

Thanks all who helped out with the suggestions. Doesn't eat coolant anymore as the new head gaskets seem to be just what the doctor ordered.

I also fixed (whilst I wuz in there:toothless);
-missing lower starter bolt:shocked,
-welded up the shorty's header ball, where I sliced through it removing the Y-pipe last November,
-lapped the valves into the seats with valve grinding compound (paste),
-new expensive type valve seals,
-Took the minimal carbon off the piston tops,
-new frost plugs in the heads,
-extracted the busted head bolt from the block:shocked
-soldered up 4 or 5 busted or frayed wires
-put new header gaskets in,
-fixed my leaking oil gauge sender at the block,
-changed the oil & filter
-lubed the chassis (wait, no I didn't !, back on the list),
-changed the remote trans filter,
-put new green high heat silicone AIR pipe hose on at the cat,
-unsized the EGR pipe at both ends and lubed it with anti-seize,
-de-rusted the huge 86 only alt/smog pump bracket and painted it,
-slapped in the proper Autolites for my E7 heads (been using ones for E6s for 10 years:brownbag)
-Did everything without removing or slacking the dist :D

Once again I thank you all for the help and support. It was a very difficult time as I'd only just tore it all apart when my mother died and it's taken me dang near a month to get it all back together.

Who knew a death in the family could be so counter productive ?

Anyways, thanks:thumbup

Sixlitre
 
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