The Stovebolt Site Forums The Shop Area Engine Shop How Do You Tighten The Bolts?

I spent 13 months rebuilding this engine, mounting it in the truck, and getting the whole mess to at least work with each other, and both head gaskets blow out by mile 34. I suspect it was my fault, no one told me what "retorque" involved until after, but I now have a new problem.

I first tossed the old head bolts (I didn't trust them, still wouldn't) and bought some ARP reusables. Pretty standard stuff, right?

After the blowouts, I start to reassemble the heads, and one of the trouble bolts snapped in half. $80 gone in the blink of an eye. I am getting pretty mad, so I decide to get TTY bolts- set it and forget, right? Thing is, no one is willing to say what to torque these things to- they say get ARPs, the same ones that failed me.

Can anyone please tell me what to torque TTY head bolts for a mid to late 70s 350 SBC?

Any Chilton's, Motors or Chevrolet Shop Manual from the late 60's will have that into and will also have the correct order for tightening them up. Were you using any manual's during your build?

I was taught to tighten all the head bolts to 1/3rd max torque, then step up to 2/3rd max torque and finally torque to 100% so you get a even stretch on the bolts...

Mike B

I have a Haynes manual that covers the 67-82 model years (I think, it is in the truck, and I'm not going out tonight). It told me to tighten it in a pattern I have seen repeated online, to 65 ft-lbs. I personally go with 25, 45, then 65. My problem was I only had single cylinder engines to go off of (My first multi cylinder engine was this 350). They said on the singles to retorque by loosening each bolt one quarter of a turn, and retorque. I have recently been told that loosening the bolts only ever happens if I am taking the heads off, so my bad.

I got new bolts at Autozone, for a 76 c30 (no that is not the truck, and the engine came out of a passenger car, but that keeps the clerks happy) with a 5.7. All the listings were for Torque To Yield bolts, no standard (reusable) bolts.

When working on my 02 taurus, I tightened the bolts to a certain torque, then turned it 90 degrees, then another 90. Never had a problem. I suspect these are a similar approach, but with no numbers I might as well use a standard ratchet, for all the good it would do me.

Torque-to-yield head bolts on a stovebolt engine- - - - - -I'd love to have a little of whatever the guy who recommended that had been smoking!
Jerry

Do you have a factory manual? Standard procedures will be spelled out there. In Iowa there should be plenty of guys on here to help you out.

Ed

I don't think what I'm assuming is a small block Chevy will have torque to yield bolts since they were never used. You can look up what an 11mm tty bolt calls for and probably get by with this reading for a 7/16 bolt. On many tty applications the bolts are torqued to a set amount and then an angle gauge is used to bring them to the yield point. We use 30wt oil to get a better reading than anti-seize or assembly lube. If a sbc then they had very little head gasket problems if block deck and head surface were finished correctly---NOT mirror finish. Our sprint cars with almost 14:1 CR alcohol engines don't blow gaskets and we shoot for 250 degree run temp. Our blown engines use O-rings which should never be necessary for a street use ride.

Well dang. That is all Autozone carried. I guess the TTY bolts are for the LT series, so they aren't worth messing with. Messing with 3 or more manuals for one truck is just asking for a migraine. Guess I'll have to order up some more ARP bolts.

Anyone got some advice on retorqueing? Run times? Do it warm or cold? I have a pair of fel pro 501SD "permatorque" gaskets, does that mitigate, or exacerbate torquing problems?

Elgin Industries small block Chevy head bolt set part # EHC-99S Plenty of similar sets on Ebay for under $30.00.

https://www.ebay.com/itm/New-Complete-Cylinder-Head-Bolt-Set-Chevy-sb-400-350-327-307-305-302-283-267-262/221346976012?epid=222845399&hash=item33894ed10c:g:On8AAOSw7a9cvHh9

Torque to 65-70- ft./lbs. in the proper sequence from any factory service manual and don't bother with a retorque. They will last through several engine rebuilds with no problems. Your first, and biggest mistake was discarding perfectly serviceable original equipment bolts!
Jerry

I discarded the bolts because they were pitting. If I threw away stuff just because it is used and old, I certainly wouldn't have bought this truck.

I hope this works this time, I really need this truck to get going.

I have reused many sbc and bbc head bolts with some pitting, 65 ft.lb. sealer on the threads and oil under the head of the bolt, no re-torque and have no blown gaskets.