exhaust leak

[alke46]

Have any of you guys or gals used an exhaust sealant on your head pipes?

I had mine removed so thought it would be a good time to replace the old gaskets. When I hooked them back onto the head and started the bike I could easily hear exhaust leakage coming from what I thought was cyl. [NODE="3"]Blogs[/NODE]

Dropped the system again and found that [NODE="2"]Forum[/NODE] and [NODE="3"]Blogs[/NODE] gaskets were loose so I swapped their places and hooked it back up. This time it was better but I could still hear some leakage.

I bought a tube of exhaust sealer from Napa capable of withstanding 1500 degrees. But before I use it, I wanted to ask for opinions -- to use or not to use and maybe a good reason if not to use.

Thanks for all responses.

 

[alke46]

While re-reading this post, I noticed on my computer anyway that the words blog and forum were put in blue highlight instead of cyl. 2 and 3.

Anyway, the leakage is either or both of the center cylinders aka: 2 & 3.

 

[rphillips]

Ummm, sounds like something, for some reason, isn't "lining up" or "tightening up" correctly.

 

[salty_monk]

Did you replace the exhaust header gaskets? They are a crush washer of sorts so you usually can only re-use them a couple of times before you need to add new (or maybe only once if they've been on there years).

They are cheap.

https://www.z1enterprises.com/exhaust-gasket-gs750-850-1000-1100-gs1150.html



I've only ever used sealant at the joints further down but most bikes don't need it.

The Delkevic pipes come with a tube of black RTV. In the UK you can buy something called "firegum" which works well at sealing leaks at pipe joints. Not seen it here.

 

[alke46]

Ummm, sounds like something, for some reason, isn't "lining up" or "tightening up" correctly.

I have replacement studs for the exhaust flanges and I tried very carefully to tighten up the nuts evenly across all eight of them. Maybe the 3rd time will be the charm I'm looking for.

Did you replace the exhaust header gaskets? They are a crush washer of sorts so you usually can only re-use them a couple of times before you need to add new (or maybe only once if they've been on there years)

Yes Dan, that was stated in the 2nd line of the 1st posting.

 

[Redman]

. I tried very carefully to tighten up the nuts evenly across all eight of them. Maybe the 3rd time will be the charm I'm looking for..
.

Loosen up the muffler mount nuts (back by foot peg) and the clamps underneath when do that.

I dont have much expereince with reusing the exhaust/head gaskets, have been told to get new ones.

 

[alke46]

Loosen up the muffler mount nuts (back by foot peg) and the clamps underneath when do that.

I dont have much expereince with reusing the exhaust/head gaskets, have been told to get new ones.

Thanks Dave, but yes, the rear mount bolts are out and I am using brand new gaskets at the head.

 

[salty_monk]

Sorry Larry, was rushing when I read your post. Maybe more pressure needed then... from memory the bolts go tight & then start to "give" as the washers crush. You then feel the washing crushing as you keep tightening, it's a pretty obvious feeling, I think you'd know if that's what happened when you did it.

 

[alke46]

No worries Dan. Tomorrow I will put the exhaust back on and report my findings. Hoping 3rd time is the charm.

 

[alke46]

Update: Bad news from my end today. The 3rd time did not turn out to be the charm. I used some masking tape on the gaskets to give them some extra thickness, hoping to cure the leak but no such luck.

Not sure what to do next but I do have a tube of exhaust sealer to try. I don't have the faith to purchase another set of new gaskets as these I am using are new ones.

I don't think it would be proper to double the gaskets on [NODE="2"]Forum[/NODE] and 3 so unless somebody here can advise strongly against the sealant, that is going to be my next move

 

[rphillips]

Shoot Larry, Are you sure you're getting the 4 little half moon pieces lined up properly. I use the masking tape to hold them in place while installing, it will quickly burn off. Masking tape on the gasket ain't gon'na to work.

 

[alke46]

Absolutely, 100% sure the half moon pieces are lined up correctly.

 

[alke46]

And Finally..............patience won out on the 4th try. I used just a very small smear of the exhaust sealer on both middle cylinders and got lucky I guess.
Started it up and could not hear anymore leakage so now it's on to synchronizing the carbs and it will be ready for a good spirited break-in.

I torqued all the flange bolts to 15# and will check it monthly to see if any further torquing is required.

 

[bwringer]

Glad you got it sorted!

I wish I could offer some sort of sure-fire solution for getting these damn things to seal, but sometimes you just have to try a few times. I always keep extra gaskets on hand.

 

[salty_monk]

I have seen a bike with new gaskets fitted on top of older ones... I never could work out if it was done by design or accidentally by the prior mechanic/owner. It worked though (and it also worked when I removed them and put one new one in....).