Fitting pipes to old Pans

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Fitting pipes to old Pans


Post by 57Kicker » Sat May 13, 2006 8:03 pm

This probably goes for just about any old hog.
I was wondering if anyone has any tips or tricks to fitting your exhaust pipes to your motor. I have an old pan and have had the pipes off about three times this past week, trying to get a nice tight seal with no exhaust leaks. I have been using brass and/or copper shim stock cut into 6 or 8 inch strips, 3/8 of an inch wide. Works good for a bit then they get blown out if the old girl backfires...pissin me off a bit.
Is there a different or better shim stock to use?
I'd sure like some advise on this...owe ya a beer!

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Re: Fitting pipes to old Pans


Post by kell » Sun May 14, 2006 3:06 am

Post by kell

I used aluminum from a beer can. Don't know if it's any better than brass or copper. But now the spigot has the Budweiser logo.

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Re: Fitting pipes to old Pans


Post by 57stroker » Sun May 14, 2006 9:05 am

Use Scotchbrite or emery cloth to clean the nipples and the inside of the pipes. Then use Permatex Ultra Black ($$$) or ultra copper silicone on your exhaust nipples. Let it sit overnight before you fire it up. The sillycone will seal the pipes, dampen vibration and help the pipes stay on. I'm running drags (I know - shame on me!!!). The other thing I did when I put my exhaust on this time was fabricate a 12 - 14" bracket with a hole in one end. I bolted the hole end of the bracket to the frame and then welded the other end to the backside of the front drag pipe. The long bracket allows the pipe to move with the motor and helps it stay on the nipple. Look at a new Harley and you will see what I'm talking about. Before I made the bracket, the front pipe would eventually creep down the nipple. Gone about 900 miles and nothing has moved yet......

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Re: Fitting pipes to old Pans


Post by 57Kicker » Sun May 14, 2006 5:45 pm

F-Y-I ... I used a beer :P can and fitted as much "shim stock" as I could in there. The aluminum seems to really work best! FOR SURE! It must be due to the properties of the aluminum in the beer can working with the aluminum in the heads combined with the heat of the exhaust. What do you think ???
Anyhoo I figure I should at least follow up with thgis to let you know of my success....WORKS FOR ME :D


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Re: Fitting pipes to old Pans


Post by kell » Mon May 15, 2006 6:41 am

Yeah. The aluminum budweiser shim I used got sintered into the spigot. Looks like a mini-beer can with lotsa soot on it. By the way I had to use the same kind of shim on that kicker gear that mounts with a woodruff key on the tapered end of the tranny mainshaft to space it so it would engage the big gear on the kick properly. That was because I had to put spacers (I used arbor spacer shims) between first gear and the main ball bearing to budge the mainshaft down to get the spacing between third and fourth back to what it should have been when the stoopit bike builder put all the nice new gears in. I couldn't space it from the other end because I needed about a tenth of an inch and you can't add that much thrust washers, or the oil seal spacer will hit the needle bearing housing. I made a post about it before. The operation was a success; my first time tearing into a transmission.


Re: Fitting pipes to old Pans


Post by pat » Mon May 15, 2006 1:05 pm

I use to have the front pipe loosen continually on my '53.
I applied the Permatex to front and back spigots, and have had absolutely no problems with leaks (unless I drag the pipes on the pavement a few times).
I have original heads, and through the years they've had a bit of material loss on the spigots.
It's nice knowing the way the pipes are set up, I won't have to worry about the front one blowing off on the freeway!

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Re: Fitting pipes to old Pans


Post by 57Kicker » Mon May 15, 2006 7:25 pm

Ok, ??? Do I apply the Permatex silicone and slip the pipes on while its workable? or try to shape the spigot and let it set up? :-/
Probly an obvious answer but I'm off to Canadian Tire in hopes to find what I need so I'll check back in later for an answer (i hope) ;D
Beer anyone?

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Re: Fitting pipes to old Pans


Post by Ente » Tue May 16, 2006 6:34 am

Hi guys.
I use the same mounting-paste as you use for mounting and tightening exhaust-system on cars (some white rubbish). It also expand a little. And for extra safety I too use extra mounting-brackets. After 7000 km it's still tight and in place.

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Re: Fitting pipes to old Pans


Post by dirtpandan58 » Tue May 16, 2006 4:03 pm

I had a problem with my front header pipe staying tight .So I put a pipe clamp on it just below the gen. strap with an angle with a hole in both ends going from the clamp to the gen.strap bolt and snuged it up. It holds the pipe on real good and solid. And you can't hardly see it unless you're looking for it.

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Re: Fitting pipes to old Pans


Post by headhog » Wed May 17, 2006 1:05 pm


Heres some information..The stock size on your exhaust flange is supposed to be 2.062 or 2 and 1-16. Measure the O.D. of your flange and the I.D. of your pipes. Then you can determine if you will be able to tighten up the pipe using the shimming process. The pipe is designed only to crush so far. The other way is to replace the exhaust flange. When my customers send me there heads for exhaust flange replacement I have them send me an accurate measurement of the exact pipes there going to use and I machine the flanges to match there pipes. HEADHOG

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Re: Fitting pipes to old Pans


Post by panfreak » Wed May 17, 2006 5:51 pm

My rear pipe was giving me a bit of grief, until I followed someones advice on this board to add a couple more small cuts to the bell end of the header with a hacksaw. I kept them short enough to be hidden by the clamp, but enough so that the clamp would actually clamp. I have repo headers that only have a small slice on either side of the pipe. Also went with beer can shim stock and a bit of ultra copper silicone. No more problem. I seem to recall awhile ago someone saying something about the copper reacting with the aluminum? Since I have done this I was a little concerned, but others don't seem to have a problem.
Opinions on the ultra copper anyone?

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Re: Fitting pipes to old Pans


Post by kell » Thu May 18, 2006 6:41 am

Right on about putting more/longer slots in the pipe where it clamps. The slots in your pipes are probably too short. They have to extend under the clamp. If your pipe only has two or four slots, think about making six or eight. Curved metal is hard to bend, but short sections of it will.

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Re: Fitting pipes to old Pans


Post by PanPal » Thu May 18, 2006 12:05 pm

Same thing on the pipes I acquired. Two slots, but they were longer than the flange. I tig welded them closed and cut four shorter slots with a hack saw. I used the red High temp silicone, no shims and SS full circle clamps. This seems to be working much better.

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Re: Fitting pipes to old Pans


Post by DanM » Thu May 18, 2006 5:54 pm

When I was doing the exhaust on my '64 restoration I found that there are two clamps used below the generator.
One goes around the pipe and helps to also hold up the flex cover. There is a second clamp that goes around the frame tube. The two clamps bolt together, and that front pipe is up there nice. Now the spigot clamp only needs to do the sealing, not the holding up.
I used stock style clamps. The pipes did have pretty long slots. I had to use a little sealer because the slots extended past the clamp when I had it up on the spigot.
See you on the road!

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