Exhaust leak

[Glenn]

I have an FMF MegaMax silencer installed on my Wolverine. The previous owner had installed it and since it's pretty quiet, I've just left it on.

It's a great system, except I have a bit of a gap between the silencer and the headpipe. I've tried to adjust it, but I can't get the fit 100% snug. I know there's a leak there because on cold starts, I get a little puff of smoke comging from the joint.

Here's a pic. I'm open to any suggestions. I tried a little flashing and hose clamps, but it doesn't seal it up tight enough.

 

[95Wolverine]

Glenn.... didn't we go through this a long time ago? I suggested that you may need to crack the head pipe nuts loose and re-adjust the headpipe - I recall back then that you thought it to be a last case option .....

My thoughts are still the same.

I'd start spraying some kind of penetrating lube on your nuts nightly and do it for no less than a week - then they should come loose rather easily. Once loose, it's fairly easy to close up the gap you have. I'd also suggest removing the headpipe and buffing the mating surface with a wirewheel to remove any "soot" that's accumulated over time and do the same to the midpipe... then seal it up with some orange Hight Temp RTV.

This is the only option my friend!

 

[deepriggin]

Your missing the exhaust crush gasket. When I replaced my stockpipe with the Supertrapp, I tried to reuse the original one. Ended up blowing out , you need a new gasket with a new exhaust. Yamaha P.N. 3YF-14755-00-00, they call it a silencer gasket. I paid about $10.00 CDN this spring for it. Take the tail pipe off and flare it back out a bit, slide the gasket over the head pipe, and slip on the muffler, clamp it up tight. I just looked at the pic again, you might have to flare it pretty good so it'll have the same I.D. as a stock muffler, but I'll bet ya whatever you pay for the gasket that it'll go.

 

[Glenn]

Robert...maybe we did. I think I posted this back on atvconnection.com. LOL! My only question on that is: Won't the headpipe just be back in the same position once I retorque the headbolts?

I tried the gasket...it's way too thick of the FMF. I didn't think of flaring it out though.

The problem with the FMF are those cuts...it's like they're too far back from where the headpipe mounts.

 

[ctateusa1]

it looks like most of it would be cured with the gasket, just flare out the pipe.

But your right it does look like it is sitting a little to far back as well.

 

[Glenn]

I'll see what I can do. The problem with the gasket is it's pretty large. On the stock muffler, the end that meets up with the headpipe has a larger diameter. The with the FMF, it's only marginally bigger than the headpipe.

 

[95Wolverine]

Yep... we covered it. lol

I know on my FMF Q series, there is no room for any gasket - let alone the stock one. Hence, the RTV silicone.

I'm sitting here thinking about the geometry relation between the two pipes and I'm not positive now that adjusting the headpipe will give you enough.

Does the muffler mount on the rear mounting bolt (back by the grab bar) or one that's closer to the engine? If its the rear, I'd take a piece of flat stock (steel) and make a bracket that bolts between the two mounting bolts. Then drill a mouting hole in the flat stock to bolt the muffler to that is closer to the front of the machine. THen you are guaranteed to get it as far forward as you need.

 

[Glenn]

Good call sir! I think that'll work. I can't remember offhand which bolt it mounts to near the rear grab bar.

If I went the flatstock route, I'd like to weld a nut to the backside of the stock...that'll hopefully ensure everything stays snug.

I smell another winter project. :lol:

 

[95Wolverine]

Instead of welding, simply use a nylong locknut or a little locktite on a regular nut - you'd be suprised at what's held together with locktite!

 

[Glenn]

Another good idea!

 

[95Wolverine]

Hey Glenn... check out this shot of the IDS2 mount on the rear - with the extension, it can act as a pivot in order to let the can move further forward.

Might be an easier fix.

 

[Glenn]

Robert,
That's exactly what I pictured! Something that will move the silencer forward maybe 1/2-3/4 of and inch. I think I'm going to fab something up this winter.

I have some flat stock at home, but I think I'll go with a thicker gauge.

 

[Glenn]

I thought of something......

The MegaMax mounts at two points: A stainless strap that mounts to a grab bar bolt and a fixed mount, closer to where the can meets the pipe part of the silencer. I believe my issue is with the fixed part of the mounting system.

Do you guys think running just the strap is ok? This would allow me to move the silencer forward, thus eliminating the gap I have.

Option two is to order another strap. Basically, the muffler would be held together by the exhaust clamp between the silencer and two straps around the can...both mounted to bolts securing the grab bar.

 

[95Wolverine]

Mine only utilizes one strap - of course, it's custom - was intended for a Warrior. After cutting the hard mount off and shortening the midpipe, it fits, but less the hard mount.

If this single strap can hold up to my abuse in Colorado, I'd say yours should be able to hold up to anything Mass, CT, RI, NH, etc can dish out.

But, mine does have a rubber insulator in between the strap and the can which keeps it from sliding around - does yours?

Went out and snagged a pic for ya - and while I was there, took another for your viewing pleasure.

 

[Glenn]

Why don't we plan on doing some parking lot engineering over some hamburgers on Sunday? We won't fix it, but rather shoot the you know what over ways to fix it. :lol: