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Bolts for Elbows

jmas

New member
Received bolts for installing

Received bolts for installing new exhaust elbows on my 454's.The heads on the bolts are 12 point and are the correct bolts for the job. They did not come with washers.
Anyone know if washers are required.
 
"maybe...if they are from OSCO

"maybe...if they are from OSCO, call them in the morning and ask them - 800-762-6726. their kits are usually pretty complete.

On my big blocks, when I switched to Barr manifolds, the washers were NOT needed. In fact, the bolts kept backing off with washers. washers gone and never burn another spark plug boot."
 
"there is very little that I d

"there is very little that I do per Osco. They warn against Stainless hardware, I use SS on the exh manifolds with split washers; But, retightening after a hot/cold cycle is a must. No blowouts in many years. They warn against RTV, I use it with success on the round gaskets; no sealant and you will have a rust mess in a couple of years in salt.
My last elbows, I installed with high grade 12pt hardware (not SS), and I also used small OD copper flat washers. So far, I'm happy. Of course the black oxide bolts like to rust, oh well..."
 
"Dave, Good idea on the Copper

"Dave, Good idea on the Copper Washers. Used light coating of Permatex ultra black on all gaskets."
 
"any idea where copper falls o

"any idea where copper falls on the noble metals chart? I know it gets green pretty fast when uncoated....Dave, how long have they been on the elbows? Also, "high grade", like 5 - maybe 8?"
 
"Copper is really active. I&#

"Copper is really active. I'd stick with all carbon steel hardware, using grade 8 stuff and lots of anti-seize. And be sparing with the silicone--globs of it can plug the riser openings and cause all kinds of trouble.

Jeff"
 
"I found copper in the noble h

"I found copper in the noble half of the charts available to me. Since they are on the dry side, its really not an issue."
 
"When replacing the long studs

"When replacing the long studs that hold the riser to the manifold, the kit comes with copper washers and brass locking nuts. Seems like the washers would act like gaskets under the nuts.
Got one set(riser/elbow)replaced and ran engine to full temp. Will retork after cool down. So far so good.
Thanks all for your replies."
 
"Pratically pure copper is use

"Pratically pure copper is used for the heat exchanger tubes, oil cooler tubes, and a few sealing washers here and there. It has a finite life in a salt environment, but its a far cry better than many other, popular materials. It is very bad against aluminum, and that is maybe why jeff gives it a bad rap. As a sealing washer against steel and iron, it works fine, and is soft enough to seal. You may notice most cars use aluminum sealing washers on the drain plug, but those are typically against aluminum oil pans, etc. In any case, I use the copper washers against the cast iron risers, and they get replaced every 4 years, due more for distortion, not corrosion. Those pieces of copper are the least of my issues with the motors and corrosion. There is one more very important place i've seen Cu washers on these engines and that's on the bolt holding on the oil filter adapter. I've got one that's 30 years old, in the salt.."
 
"oh yeah, Mcmaster carr page 3

"oh yeah, Mcmaster carr page 3119; > grade 8. 180,000psi rated. Small 12 point head enables a better wrench fit in there."
 
"Or, you can go to Sears and b

"Or, you can go to Sears and buy a 6 point combo wrench (box/ open end). Got a 1/2 and a 9/16 on my boat.

Jeff"
 
"Joe,

You are correct. The


"Joe,

You are correct. The relatively soft copper washers do act as a seal since the bolts go through an area in the riser that is within the water jacket. The plastic inserts in the nuts seal the threads on the bolts. Poor design in my mind. This is for the older Log Style manifold/riser/elbow combos. I don't know about the center stype of manifolds that may use a spacer (or riser) and then the elbow.

Erich"
 
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