dirt through the muffler?

[The motor guy]

What keeps dirt from getting into an engine through the muffler? Say for example on a weed eater when your blowing dirt and grass around when it's laying on the side walk whats keeps grass and dirt from flying through their and getting into the combustion chamber? I guess on a car that doesn't happen cause it has to go a long ways to get through.

 

[NHGUY]

Hopefully the engine valves allow exhaust to escape but not to suck in air.Thats the job of the intake valve (carburetor).

 

[Hokiefyd]

Most all mufflers have a number of chambers inside. Small engine mufflers aren't all that dissimilar from a Flowmaster muffler, except that there are no "flow directors" to speed exhaust flow. I'd think that it'd be extremely hard to blow anything into the combustion chamber backwards through a muffler.

 

[morris]

vandalism?

 

[mechtech2]

For one, thing, the catalytic converer would preclude this type of material from entering the combustion chambers.
It would be miraculous anyways for debris to go very far up the exhaust system.
I don't think you could cause a problem if you TRIED to - [from yard work].
plus, it would blow out almost immediately when you started the vehicle.

 

[Kruse]

On an antique car with no catalytic converter, I've seen some mice travel all the way up the exhaust and build in a cylinder. But it was a car that had been parked awhile and who knows how long it took. In a late model car with a good exhaust and especially a catalytic converter, getting dirt in an engine through the exhaust is the least of my worries.

 

[Vikas]

I have heard that some of the Nissan engines manage to ingest disintegrated catalytic (pre) converters back through exhaust valve and scoring the cylinder walls in the process. I personally do not quite understand how that is possible but many respected members have made this claim and I do trust their technical knowledge.

 

[mechtech2]

Originally Posted By: Kruse
On an antique car with no catalytic converter, I've seen some mice travel all the way up the exhaust and build in a cylinder. But it was a car that had been parked awhile and who knows how long it took. In a late model car with a good exhaust and especially a catalytic converter, getting dirt in an engine through the exhaust is the least of my worries.


Way true! Nests and droppings from mice are common is old stored cars. Even acorns jammed in there from pack rat squirrels! I recommend rag stuffed in the exhaust for long term storage.