View Full Version : o-ring or band style intake

26th March 2005, 08:49
I am about to order an S&S super e carb for my beyond custom 76 ironhead. Problem is that I am not sure if it has band or o-ring intake manifold gaskets. IT MAY NOT HAVE THE ORIGINAL HEADS. The carb / manifold I took of apears to be an 83 or newer jap carb and I THINK IT HAS BAND INTAKE.
So my question is this.
A: pics of both would solve all problems
B: what is used to hold O-ring style on the bike? And its an actual O-ring right?
C: Mine had "square" o-rings inside the "bands" that held the carb to the head.... I mean the were round in shape but not made of round material.... ( Make sense???) is this a Band??
Thanks all, I am trying to get my 8 foot monster to run a whole lot better as I am getting too old to re kickstart it at everyother stopsign.

26th March 2005, 13:18
i have a 75 ironhead with an s&s carb and it has o-ring gaskets it a little tricky you need to push when u tighting down clamps so they will seal or u will have an air leak lernd this from dum mastake.they do sell clamps with rubber around the in side would use both if can

27th March 2005, 01:17
My 1980 had the band type rubber seal. When i was doing some work "everyone" said i should go with the o-ring seals instead, that they are better. "Everyone" is mainly the local trusted expert inde.

The o-ring seals are real o-rings. They are held in place with a style of clamp called "aircraft clamps". Real nice clamps; stainless steel i think. You can buy a kit that includes the clamps and the o-rings.

The o-rings are a bit of a trick to get in. I had to install one o-ring and clamp, then the manifold, then the other o-ring, and finally the other clamp, which i had to undo to install. Someone else on this forum recently said they were able to install both o-rings and clamps, then install the manifold. Not on my bike.

The o-rings are "too small" and this is where the trick comes in. Have to install the far side of each o-ring 1st, then squish the near side into place. Feel inside the manifold to ensure they are correct.

27th March 2005, 05:01
Your square o rings were round when they were new. The clamp pressure on the outside flattened them over time. It's this pressure that creates the seal. Making sure the position of the new o rings is clean, roll your new o rings up on the intake ports of your heads. Position your intake manifold and gently roll them down into place.Using your fingers inside the manifold make sure it is lined up. The o rings will almost hold the manifold in place. Now wrap your band or aircraft clamps around the o rings and gradually tighten front & rear back and forth until they are both tight and secure and the inside joints are smooth. (lined up)
Make sure the weight of the carb & air cleaner is supported by a bracket. An s&s air cleaner has a hole in the back plate for a bracket that mounts to one of your lifter block bolts. If you do without this support bracket the carb won't fall off right away but after a while the seal will open and you will be sucking air. And oh yea, I have seen the whole manifold, carb and breather come loose and hang from the throttle cable (not my bike)
If you remove the carb for any reason, take the opportunity to replace the o rings. Throw the square ones in the garbage. They have lost their elasticity.
Hope this helps.