Rodent Nest Under Engine Cover - Fire Risk?

[Number_35]

A few days ago I replaced a rear shock mount on an old Mazda5 for an elderly friend.

Afterwards I gave the car a general look over - checked the oil and other fluids, aired up the tires, etc.

I pulled the plastic engine cover, and was surprised to find a rodent nest on top of the engine.

I removed most of it by hand, and finished up with a shop vac. There was no evidence of mice or squirrels (the most likely culprits here). I figure most of the material is the sound-deadening insulation that used to be attached to the bottom of the engine cover.

Idle curiousity - did this material pose a fire risk?

 

[fantastic]

They love the covers! That is quite the nest though. wow! It's that time of year.

 

[Dave Hess]

Maybe if the rodent nest was closer to firewall / exhaust manifold.

 

[hemitom]

There is flammable debris in the mix and like Dave said close enough to the exhaust I think that would burn .

 

[AZjeff]

Here if a car is seldom used and sits outside it's a surprise if there isn't a nest somewhere. No chewed wires?

 

[NibbanaBanana]

Get rid of the engine cover. Mice did that under the cover of my wife's Kia Rio. They chewed the coil on plug wires. And they got a lot of nesting material on the catalytic converter which ended up catching on fire. I would clean it out and they would build it back up by the next day. Tried trapping but they always came back. Remove the engine cover and throw it away.

 

[wwillson]

They love the covers!

I removed the engine cover on every vehicle I own to keep rodents from building nests and chewing on wires.

 

[Number_35]

Here if a car is seldom used and sits outside it's a surprise if there isn't a nest somewhere. No chewed wires?

There were none evident. Despite the excessive rust, the car runs and drives well. I figure a chewed wire would result in a CEL or drivability issue.

 

[Number_35]

I removed the engine cover on every vehicle I own to keep rodents from building nests and chewing on wires.

Engine covers are said to be helpful here in the winter, allowing the engine to come up to operating temperature quickly, and to maintain temperature.

That said, I plan to remove the cover from Jr's Mazda5, reinstalling it for December through February.

I will recommend same for any other vehicles I help out with.

 

[ARCOgraphite]

Had the same thing occur on a FORD/Mazda 2.0 liter in my '20 Ford EcoSport AWD.

Took the cover off. Same car I later had squirrels stashing dozens of acorns between the hood insulation pad and the hood!
When I traded the car I couldn't find where I stashed the cover. A month later I found it in my basement storage room. Somehow I missed adding it to my xL "wherisit" spreadsheet I created a couple decades ago

 

[50yr Street Mech]

Fire risk ? Depends what's in the mix. If it's mostly noise suppression material, I'd say no. I would DEFINETELY check the cabin air filter. They love to nest there due to the heat from heater core. I've had that on a few cars already. They make home right on top of that filter. Those little buggers can find their way thru any duct work. The filter stops them from going any furthur. Also, don't park the car in grassy areas. Like putting up a lighted vacancy sign ! Park in garage or on asphalt. Good catch. You're a good friend to go the extra mile looking for things

 

[loneryder]

A few days ago I replaced a rear shock mount on an old Mazda5 for an elderly friend.

Afterwards I gave the car a general look over - checked the oil and other fluids, aired up the tires, etc.

I pulled the plastic engine cover, and was surprised to find a rodent nest on top of the engine.

View attachment 300406

I removed most of it by hand, and finished up with a shop vac. There was no evidence of mice or squirrels (the most likely culprits here). I figure most of the material is the sound-deadening insulation that used to be attached to the bottom of the engine cover.

Idle curiousity - did this material pose a fire risk?

I keep a block of muse bait/poison on top of my battery on my 01 F150. Had nests and even a flattened dehydrated rat under the engine cover. Also they chewed holes in the hood insulation and filled it up with acorns. No problems since I started leaving the bait under there.

 

[goofy]

I keep a block of muse bait/poison on top of my battery on my 01 F150. Had nests and even a flattened dehydrated rat under the engine cover. Also they chewed holes in the hood insulation and filled it up with acorns. No problems since I started leaving the bait under there.

Do you prefer a particular brand/type of poison?

 

[loneryder]

Do you prefer a particular brand/type of poison?

I'll look but it's the one you find at Walmart or Tractor supply.

 

[ARCOgraphite]

What happened to the the old 'mothballs in panty hose' trick. And did it ever it work?

 

[goofy]

What happened to the the old 'mothballs in panty hose' trick. And did it ever it work?

I have not seen mothballs at the dollar store since they broke the buck.

 

[ARCOgraphite]

Do you prefer a particular brand/type of poison?

Bad for Owls and Hawks and Eagles you goof!

Just say NO

 

[goofy]

Bad for Owls and Hawks and Eagles you goof!

Just say NO

Then they need to do a better job.

 

[50yr Street Mech]

Smart move putting bait under the hood

 

[Number_35]

There's a cat bylaw here, which has resulted in less risk to birds, but also an abundance of squirrels and rabbits.