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Few questions on assembling a 350.

y5mgisi

y5mgisi

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I Just got my heads back from the shop and i need to know a couple things. First should i use loctite or anti-sieze on the head bolts? Second does anyone have the torque specs for the rod bolts and main bearing bolts? I also need torque specs on the head bolts them selves now that i think of it. I need help. I want to finish assembly tonight!
 
i always use rtv on sbc head bolts. They feed directly into a water jacket. Ultra black is what i use. in storage is my sbc book, just get a book for 15 dollars, it tells you damn near everything.
 
you don't want loctite or anti-sieze on the hed bolts, but a thread sealer as they thread into the waterjacket in the block. i have always used teflon tape without a problem but i have heard it can have an affect on the torque specs.

can't think of the torque specs off the top of my head, but i think the rod caps are 45 ft/lbs.
 
I only use a drop of oil on each head bolt. Make sure that the head bolts are clean and also that the holes in the block are clean.

Head bolts = 65 ft. lbs.
Main bolts = 70 ft. lbs.
Rod bolts = 45 ft. lbs.
 
Year doesn't matter and either does 2 or 4 bolt. I do this for a living every day. Trust me on this.
 
I do as Scott mentioned. Clean bolts and holes, just oil on threads.. ensures proper torque... I've probably done a hundred sets of heads, never used a sealant and never had an issue...
 
Ive never used oil or sealant on any of mine. in fact Ive never heard of it being done. never had any problems either.
 
4X4HIGH said:
Year doesn't matter and either does 2 or 4 bolt. I do this for a living every day. Trust me on this.
Click to expand...
i thought the outside bolts on the 4 bolt were like 5 ft/lbs less? so it would be 70 for inside bolts and 65 for outside bolts. is this right? its what my haynes manual says.
 
4X4HIGH said:
True, but you can put them all at 70 ft. lbs. won't hurt a thing.
Click to expand...

with the exception of the main bore, that is, unless your machinist screwed up just like you did.
 
I have been building engines for 20 years PROFESSIONALY and 70 ft. lbs. is an acceptable torque value for a 4 bolt block. It will not distort the main bores like you're thinking it will.

So Beater_K20, which book should i scan for you?
My 1971-1978 Chiltons book says main bolt torque 70 ft. lbs.
My 1979-1986 Chiltons book says main bolt torque 70 ft. lbs.
My 1986-1990 Chiltons says 2,3,4 bolts 70 ft. lbs. other bolts 80 ft. lbs.
 
According to the Chevy power manual when assembling a production block you are supposed to use a thread sealant on the head bolts, since they thread into the water jacket. Not doing so invites the possibility of your new motor losing water and gaining oil :doah:. The only time you don't need to use sealant is if the block has blind-tapped holes (the holes don't penetrate into the water jacket) - AFAIK no production block is blind-tapped, only Bowtie blocks and some aftermarket blocks are that way. In the holes are blind tapped, use 30wt oil instead of sealant.
 
don't rush anything dude. make sure you plastiguage everything possible to make sure your clearances are right. it was real helpful to me to have some assembly lube in an aerosol can for getting everything lubed up right. my situation was a bit different, b/c it's diesel, so i won't add much on putting it together, but the instructions above all seem real close to what i did.
 
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