Exhaust pipe wiggle, normal?

[k1hog]

Under coach to check things, and found the exhaust pipes wiggle quite a bit, no hangers missing. Is this normal?

Johnnie

[DriVer]

Quote:

Originally Posted by k1hog Under coach to check things, and found the exhaust pipes wiggle quite a bit, no hangers missing. Is this normal?

Johnnie, I had the same concerns. There is an allowable range of motion on an exhaust system under a gas powered motorhome. It should not be rigid from the headers to the tail pipe nozzle.

[monarchman53]

My rigs' exhaust is in perfect condition and I too have thought there is a lot of movement which doesn't concern me as much as the fact that both pipe ends seem to be hanging quite low to the ground.

[DriVer]

Quote:

Originally Posted by monarchman53 My rigs' exhaust is in perfect condition and I too have thought there is a lot of movement which doesn't concern me as much as the fact that both pipe ends seem to be hanging quite low to the ground.

monarchman53, On my Winnie I have just about 12" of ground clearance. Some Gulfstream coaches I bet might only have 6 inches it would seem - they look so low to the ground.

Exhaust pipe exit height is all dependent on the OEMs need to clear the body work of the motorhome. With the exhaust pipes being mounted close to he rear tires it is expected that the tips won't strike the ground but I have seen several bent or crushed pipes in my travels.

[wa8yxm]

Not only normal.. IT is absolutely REQURIED Though you might check for flexing at the pipe - manifold connection (some are spring loaded to allow movement)

IF you were to mount a camera where it could watch the engine as you go up and down hills you might well be amazed at how much it moves.. .That pipe has to move or break. Those are its only choices. So movement is allowed for by the hanger straps.

[scenic route]

WOW! I love this site! This Tuesday I was going to tighten the Bjesus outta our exhaust system at the same time I was going to change the oil/fliter. No leaks but there is some movement in the system.

iRV2 is better 'n PORK...it's about the third time you guys have save my 'BACON'! Thanks, Bob

[MntDriver]

Hold on there, as I believe the movement on the hangers a BIT is ok, but the donuts being completely loose is not.

Check out this post on the repair.

2006 Workhorse W-22 mufflers rusted out!

[DriVer]

Quote:

Originally Posted by MntDriver Hold on there, as I believe the movement on the hangers a BIT is ok, but the donuts being completely loose is not.

I don't think that anyone suggested that ... I don't see anything on the page that says that the donuts must be tight. Mine are loose just a little bit and they aren't leaking.

[ron55]

If it is wiggling at the exhaust maifold (donut gasket) it leaking fumes

[DriVer]

Quote:

Originally Posted by ron55 If it is wiggling at the exhaust manifold (donut gasket) it leaking fumes

Ron55, That's not going to be a good thing if that happens. I'll need to keep an eye on mine. I remember a while back when the connections on some cars were made up with springs and it wasn't supposed to be rigid. Over time the springs didn't survive very well.

[MntDriver]

Quote:

Originally Posted by ron55 If it is wiggling at the exhaust maifold (donut gasket) it leaking fumes

I believe this is correct....it is fine to have free movement with the hangers, but free movement at the donuts is not correct....these should be fairly tight like the repairs in the thread listed. On mine, you can push up on the exhaust pipe at the donuts with your hand and completely push the pipe off the donut seat/gasket, and this will cause slight leaks under pressure.

The largest exhaust shop where I live says they replace 2-3 donut sets per month on these 8.1 liter motorhome engines because if your exhaust system isn't hanging exactly perfect on the donut, you will burn out your donut gasket.

[DriVer]

Quote:

Originally Posted by MntDriver The largest exhaust shop where I live says they replace 2-3 donut sets per month on these 8.1 liter motorhome engines because if your exhaust system isn't hanging exactly perfect on the donut, you will burn out your donut gasket.

I will no doubt have to have that repaired then. I don't feel at all comfortable in honking on those nuts because I don't want to break the studs.

I checked by pipes again today 1 tight - 1 not so tight.

[AFChap]

The connection from the header tube to the exhaust pipe should not be flexible, but from there back most systems include pipe hangers with rubber straps or rubber rings which will move/wiggle a bit.

[62Morgan]

Don't forget your bodywork.

I had enough end play at the tip that allowed vertical travel to scorch an oval into bottom edge of basement door. This on an 2004 gasser. Strapping and rest feel solid. Just appears the last strap location allowed it to pivot up at the tip. I find myself constantly nudging it down to ensure it doesn't make contact again. Perhaps I need to re-examine.