Exhaust noise

[Bluebird John]

I have two John Deere L110 lawn tractors. One runs perfectly quite (except of course the normal engine noise). Both have the Kohler 17.5 hp engine. CV491/27509

The other one I purchased from my next door neighbor and it is NOISY. Initially I thought it was the gasket on the exhaust pipe and I replaced it. Did not help. I thought also it could be the muffler or baffle inside the muffler, but the muffler looks good and the baffle inside it is intact. The lawn tractor runs great, starts great and has no problem running. Power output is good.

The noise is really getting to me. I am now thinking it could be the head gasket, but am not sure. The noise is not a popping noise, it just sounds like an exhaust noise.

Any suggestions would be appreciated.

John

 

[ILENGINE]

Make sure there isn't sheet metal vibrating around the muffler, that can be quite noisy sometimes. A video of the engine running might help us to narrow down your problem.

 

[lugnut1]

As Iengine stated look for sheet metal vibration

tip:
(you can use a screw driver and press on sheet metal in various area's of the engine
to try and locate any rattles.)

I had a briggs engine that had a rattle
(found that the recoil cover nuts that secured the plastic cover on were loose in their mounts.)

 

[KrashnKraka]

I have two John Deere L110 lawn tractors. One runs perfectly quite (except of course the normal engine noise). Both have the Kohler 17.5 hp engine. CV491/27509

The other one I purchased from my next door neighbor and it is NOISY. Initially I thought it was the gasket on the exhaust pipe and I replaced it. Did not help. I thought also it could be the muffler or baffle inside the muffler, but the muffler looks good and the baffle inside it is intact. The lawn tractor runs great, starts great and has no problem running. Power output is good.

The noise is really getting to me. I am now thinking it could be the head gasket, but am not sure. The noise is not a popping noise, it just sounds like an exhaust noise.

Any suggestions would be appreciated.

John

I thought I had answered this post elsewhere with a test for the noise source.
You have not seen my post?

KK

 

[Bluebird John]

I thought I had answered this post elsewhere with a test for the noise source.
You have not seen my post?

KK

Yes, I have seen your post. Thanks very much.

I have done some additional testing. I removed the muffler from the tractor that sounds normal and put it on the noisy tractor. The noise it still there. I am almost convinced it is the head gasket as it sounds like an exhaust noise/compression noise and not a rattle.

 

[KrashnKraka]

Yes, I have seen your post. Thanks very much.

... no worries, yer welcome.

I have done some additional testing. I removed the muffler from the tractor that sounds normal and put it on the noisy tractor. The noise it still there. I am almost convinced it is the head gasket as it sounds like an exhaust noise/compression noise and not a rattle.

There would then be other differences between the two mowers?
If not then it is back to gasket and/or manifold cracked, I offer.

KK