Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet Iron Barrel => Topic started by: jdrouin on October 05, 2012, 04:18:39 am

Title: Fixing Header Exhaust Leak
Post by: jdrouin on October 05, 2012, 04:18:39 am
I have the exhaust pipe (short English model, no PAV) off the Bullet right now because I'm fixing an exhaust leak where the header pipe fits into the head. Going to use Permatex Copper gasket maker to seal it.

I've never done this before, so I'm wondering how you guys would recommend I de-coke and clean the mating surfaces of the exhaust port and header pipe.

Once those are clean and dry, I figure I'll apply the gasket maker generously inside the exhaust port and around the top inch or so of the header pipe, and then re-insert it.

Also, it seems like I might want to remove the brake pedal to make it easier to slide the pipe back on, but I'm not entirely sure how to do that. I undid the screw that tightens the clamp and there are these weird nipple-like things on the ends of the bar that I've never encountered before (on machines, anyway).

Many thanks for any tips you might provide.

Best,

Jeff
Title: Re: Fixing Header Exhaust Leak
Post by: Chuck D on October 05, 2012, 12:25:33 pm
Hi Jeff,
Fine steel wool and some kerosene and elbow grease should clean up that area nicely.
The permatex copper works pretty well but allow it the full cure time. I'd say wait 24 hours before starting up the bike.
Getting the brake pedal out of the way will obviously help. Just take off the adjusting nut from the back of the rod and slide the rod out from the actuating arm, freeing up the linkage and allowing the brake pedal arm to just flop down out of the way.  Unhook the little spring that pulls the brake light switch as well.
Those weird nipple like things are grease "zerks". You attach the business end of a grease gun to them and fire away.
Chuck.
Title: Re: Fixing Header Exhaust Leak
Post by: jdrouin on October 07, 2012, 02:19:38 am
Thanks Chuck! I used some generic O'Reilly's degreaser I had lying around and it worked well. Dry steel wool was actually pretty effective at removing coke before I even applied the degreaser.

My only concern now is that I might not have used enough gasket maker to form a seal. We'll find out out when I start it up on Monday.

Jeff
Title: Re: Fixing Header Exhaust Leak
Post by: Chuck D on October 07, 2012, 03:08:16 am
Thanks Chuck! I used some generic O'Reilly's degreaser I had lying around and it worked well. Dry steel wool was actually pretty effective at removing coke before I even applied the degreaser.

My only concern now is that I might not have used enough gasket maker to form a seal. We'll find out out when I start it up on Monday.

Jeff
Oh, really?
Title: Re: Fixing Header Exhaust Leak
Post by: jdrouin on October 08, 2012, 02:43:45 pm
Boy, I did a terrible job. Started the bike this morning and apparently there was some wet sumping. White smoke came out the tail pipe on startup, but also at the header where I just tried to fix the leak. Smoke out the header never happened on wet sumping before.

Unless anyone can tell me the gasket maker will give off smoke the first time it gets hot, it looks like I have to try again.



Title: Re: Fixing Header Exhaust Leak
Post by: ERC on October 08, 2012, 03:39:15 pm
You'll have to try again. Remember let it dry at least 24hrs.  :'(  ERC 
Title: Re: Fixing Header Exhaust Leak
Post by: jdrouin on October 08, 2012, 04:05:27 pm
It dried for almost 48 hours, but temps here got down to the 50s and 30s. The Permatex tube says ideal temp is 70.

I think I placed the gasket maker poorly. I put some around the inside lip of the exhaust port, where the header pipe would land if it went in all the way, as well as around the pipe at about 1/2" from the opening.

I don't think the pipe went in all the way to the lip, so that bead was simply wasted. Now I'm thinking I should line the exhaust port near the outside opening and the pipe near the end, so the gasket maker comes into contact with itself at the beginning of fitting the pipe. Maybe if the two rings of wet gasket maker meet as the mating surfaces move past each other, they'll form a better seal.

Any advice or experience here would be much appreciated. Thanks!

Jeff
Title: Re: Fixing Header Exhaust Leak
Post by: baird4444 on October 08, 2012, 04:17:12 pm
I always wiped both sides with rubbing alcohol to remove any oils at all. then ran maybe a 1/4" bead around the edge of the pipe. When inserted it just smears down the edge to fill. Then smooth joint when tightened. If none on outside I'd run a small bead round WHOLE circumference. Must let dry for 24 hours...  might consider a light to warm and help cure.
Title: Re: Fixing Header Exhaust Leak
Post by: barenekd on October 08, 2012, 08:49:25 pm
The white smoke is probably condensation in your pipe. Very common in cold weather. Sump oil is normally blue/grey.
If you're pipe is that loose in the head, get some aluminum exhaust tape at your auto parts store and wrap the pipe with a layer or two until you get a snug fit.
Bare
Title: Re: Fixing Header Exhaust Leak
Post by: ERC on October 08, 2012, 10:47:18 pm
Put the pipe in as far as you can get it then mark it. Then when you put it in with the sealer you'll be able to tell if it will hit the sealer or not. You'll have to get all the old stuff out because silicone won't stick to itself.     ERC   
Title: Re: Fixing Header Exhaust Leak
Post by: Afro Samurai on September 19, 2013, 01:28:21 am
I just did this seal repair with the permatex copper...been running it for about 8 days...seems to be holding up...

That is a really horrible fit with the exhaust...
And my pipe has such a long gentle bent...its tought to drive it home without fear of denting it... (thats what she said)
Title: Re: Fixing Header Exhaust Leak
Post by: Blltrdr on September 19, 2013, 01:32:38 am
I think Ace suggested once to take your header to a muffler shop and they can expand the end a bit. He also suggested using a piece of aluminum from a coke can to fill the void before using a silicone sealer. If you have a problem again you might try one of these solutions.
Title: Re: Fixing Header Exhaust Leak
Post by: D the D on September 19, 2013, 01:34:41 am
I covered the entire inside of the head from the step the pipe seats on to the outside then coated the entire pipe for the length it goes into the head.  After pounding the pipe in with a rubber mallet, I cleaned up with Popsicle sticks and paper towels wetted with strong vinegar.  Any that flows into the inside of the pipe will burn off and you'll smell it at first start.  This worked for 4 months and 1200 miles until the Nissan kissed her and pulled the pipe completely out of the head.
Title: Re: Fixing Header Exhaust Leak
Post by: RGT on September 19, 2013, 08:13:49 am
as ERC said put the pipe in and mark it, check how far it is going in if it is not going very far in see why, I have had to adjust, bend, file mounts to get the pipe to go in deeper. I have had to bow the top mount that attaches to the front down tube quite a bit sometimes. I have found that while  forcing the pipe in and using a mallet on the front strap mount I can watch the pipe get drawn in then adjust your other mounts such that they help hold the pipe in not force the pipe out. I have also used aluminum can shims and or brazed up the pipe end to make a tighter fit.