Hello All,
First post! Greetings from Maine, I've got an 82 Ironhead I bought a year ago that was rebuilt not too long ago. I was having horrendous idle problems and finally (with a little help) figured out the rubber bands on the intake manifold had ripped. I noticed there is a slight (business card) gap between the manifold and heads. Is this ok? Ive been told to either loosen the heads or the bottom cylinder nuts to align the intake w/ the heads. Either way I think I'm sure to tear a gasket. Any thoughts?

 

It shouldn't hurt as long as you're getting the rubber bands seated. I haven't looked any Sportsters as new as yours, but we always put white grease on the O rings. That helps the seal and also keeps them in the groove.

 

Welcome aboard!
The gap between the manifold and head(s) is OK. The important thing is that the gap is even, or I should say 'that the edges are parallel.' The O ring(s) sit centered in this small gap and compress and seal as you tighten the clamps.
To correct any misalignment, loosen the 4 cylinder base bolts and tap the cylinder with a plastic mallet. That gasket is stuck to the aluminum by now, so it will not be harmed. You only have to move the cylinder a small amount in the worse case.
Whatever you do, DO NOT loosen the head bolts to move the heads. That can cause you all kind of problems.
After you have aligned it as best you can, tighten the base bolts and install the manifold with new O rings.
I do that using this method:
Carb removed from manifold.
Put your fingers inside the manifold so that the fingertips are on the O ring. Feel how it sits in the grove. It should feel even all the way around.
As you tighten the clamp, keep moving the fingertips around the O ring to detect any movement. No movement, you are good.....When the installation is correct, you should feel the O ring surface is flush with the inside bore of the manifold all the way around. If there are any bumps or irregular spots, you need to start over. Now do the other one.
Last of all of course you install the carb.............pg

 

The slight gap will be no problem as long as the sealing bands cover at least a half inch of the manifold and the heads. When I replaced mine I used new stock bands and the clamps are two half circle clamps the use an Allen head bolt on each side of the clamp. These are a lot stronger than the factory type clamps and seal better. If I remember right the clamps came from V-Twin Manufacturing.

 

If I may, the 'sealing bands' do not seal. What seals is the rubber O rings being compressed into expansion by the pressure of the clamps. All the clamps do is to compress the O rings. After both clamps are tight, you can still wiggle the carb until you install that all important carb bracket that attaches to the lifter base. Now you cannot move the carb.......pg

 

I'm not sure but factory changed "O-ring type" manifold and cyl.head to "rubberband -type" in 79 or 80 models (might be also later). If engine is assembled from "basketcase" parts can be mixed...
Newer heads don't have that grove, insert is smooth same in manifold.

old_____ ______ new _____oooooo________
\__ O __ /

carb -> manif -> O-ring -> Head manif -> Band -> Head

 

'79 was the first year that the wide bands were used.

 

Yep, you and sepixlh are correct. I was in error to say that O rings are used. Sorry, I was thinking in terms of before 1979.
Some day I will learn my lesson,..I hope.....pg

 

Nobody can't be expert to all years and models [&:] You PG are true expert when we are talking about older IH [sm=icon_cheers.gif] I personally know only little about 72-79 IH's but I think it's important that whole "group" support each other. This because there is very few workshops that really are willing to work with IH or older models, they don't care theese "old scoots"

-sepixlh-

 

Well stated sepixlh, I agree 110% with that. The group working together to solve Sporty problems......... I think our group does that pretty well. A rider cannot even hope to find answers to ironhead problems at a dealers, so this forum has a great purpose and I am proud to be a part of it........pg