Intake bolts

[bw4sale]

Sorry for the novice question, but I'm new to rebuilding engines.

I freshened up my 350 a little while my truck is blown apart. When I put the intake back on I just torqued the bolts as the manual said. Later, I heard something about putting some kind of sealer or antisieze on them. I've got to pull one of them out to replace it with one that has the extra thread on top so I can brace my serp set up.

1) Do I need to pull them all out and put something on the treads? If so, what?
2) Do I pull them all out at once and retorque as the manual says or can I just pull one at a time and then retorque?

BTW, the motor hasn't been run since I put the intake on. Thanks.

[Lee H]

You don't "need" anti-seize if your putting steel bolts into a steel cast block. You only "need" anti-seize if you have dissimilar metals like stainless fasteners into cast or stainless or steel into aluminum. That said it never hurts to use a little, I do. As for the sealer, the 4 inside fasteners on each side are open to the lifter valley and will eventually start weeping oil onto the manifold. You can simply pull them out one at a time, use a thread sealer like ARP or Permatex thread sealer (stay away from silicone for thread sealing) and re-torque them.

[bw4sale]

Great. Thanks for the info.

So, on the 4 inside bolts, do I need sealer and anti-seize or will the sealer do?

[GASoline71]

I always use a little thread sealer on intake bolts. Especially the ones that are open to the lifter valley. If no sealant is used... oil can creep up the threads over time and slowly leak onto the manifold.

Gary

[cdowns]

there are bolts on the intake that need to have a good quality thread sealer applied or else you end up with oil leaks and puddles of oil on your nice clean intake

[rfmaster]

Yes, the engine oil has a tendency to seep around intake manifold threads, especially on older heads (threads in the head are corroded and worn). I use a combination of black RTV and new, quality USA made bolts (3/8-16 x 1''). Chinese made bolts tend to have smaller major thread diameter (0.3656 to 0.3666) - just few mills or so when you take calipers to them (0.3750 is max). While couple of mills does not sound too much it makes a difference between a 'dry' engine and a 'wet' intake! ARP bolts are always on the money - but prepare to pay $19 for a set of USA made bolts vs. $9 Chinese Commi made crap.

//RF

[prostreetC-10]

Don't know if it's a bbc thing or not but I put sealer on every intake bolt. I never have oil leak but certainly had coolant leak onto the intake.

[bw4sale]

Just so I'm sure. You don't put anti-seize on the bolts that you put the sealer on, right? Not sure how you could do both.

[rfmaster]

Originally Posted by bw4sale

Just so I'm sure. You don't put anti-seize on the bolts that you put the sealer on, right? Not sure how you could do both.

You do not need to put anti-seize on intake manifold bolts (SBC -GEN1). Bulk of the bolts thread trough into the central oil galley. IRC, only the outside 4 bolts are blind. Since there is no coolant that may come in contact with the bolts - there is no need for anti-seize. A good doze of Black RTV on the treads will do the double duty of sealing and keeping bolt from seizing.

//RF

[prostreetC-10]

Not anti-seize. Thread sealer or liquid thread tape. I use Prematex sealer.

[Captainfab]

Also if you are not using original intake bolts, be sure they are the correct length. There are a couple holes where too long of bolts will contact the pushrods.

[GASoline71]

Just cuz they're going through an aluminum intake don't mean t=you need antiseize. Just pllain ol' thread sealant is needed.

If you had aluminum heads... maybe a different story.

Gary

[storm9c1]

Question...do Vortec heads (with vertical intake bolts) have the same issue? I don't remember...I never used any sealant on Vortec heads, but maybe I'm doing it wrong...

[LostMy65]

While I had my cab and front clip removed, I pressure washed my sbc engine, and then ran it for awhile to see if I could locate my leaks. I thought they were coming from the valve cover gaskets, but it's actually leaking around the intake manifold bolts. Can I just take the bolts out one at a time and do the sealer on the bolts and holes, or do I need to remove my intake manifold and start over?

[GASoline71]

Take 'em out one at a time.

Gary

[LostMy65]

Thanks.
What sealer would you recommend?

[LostMy65]

I did find this post:

Originally Posted by Tony

I just assembled a SBC.The machine shop recomended either Permatex Aviation gooey brown stuff in the small white bottle or Permatex Hi Tack in the small metal can for head or intake bolts.They claim this is especially true on a head or manifold change on a running engine that the threads my be a little dirty.The shop builds a lot of performance engines,they say no come backs for leaks with this stuff.The Teflon sealer works ok,but if there's any dirt or oil on the threads ,it doesn't work sometimes.

[LostMy65]

I took the three out that were leaking. One at a time. Wiped them down and put the Permatex Aviation gooey brown stuff gooped on. Torqued them.
How long until it all sets up and I can start the engine and see if all is good?

[GRX]

"How long until it all sets up and I can start the engine and see if all is good? "

Over night will be sufficient.

[LostMy65]

Ran it for a good 10-15 mins. Revved it up to 3000 rpm for a good duration. Not even a slight sign of oil leaking.
Thanks everyone.