How do the mice get in?

I asked that question of a GM designer while at a workshop. I was told that some time ago GM started managing airflow through the cars rather than assuming they would leak (he said that tongue in cheek). He thought it started in the late '60s - early '70s; early versions of this flow thru ventilation had (a) heater fans that never really turned off (b) vents under the rear window. You may remember the Chevies for instance with the HVAC controls marked "Astro-vent" and fan switches that had lo and hi but NO 'off.' Problem with those, though, was that the trunk could accumulate moisture and condensation in some (well, most really) locales. Cure for that was to pop out a body freeze/drain plug in the spare tire well... anyway, it was not that long before they started intentionally venting the trunk. In field testing one vent was adequate so although the stamping has the blind hole for a second vent I am not sure how many if any were installed in Rivs that were sold to the public. Anyway in most late model high line GM cars you will find some sort of a trunk vent in what the wind tunnel indicates would be a low air pressure area under a moving vehicle.

As for our cars: air from the Riv cabin, I was told, escapes by the lower outboard corners of the rear seats and (sort of) thru the rear speaker baffles in the rear deck. The rear window tended to fog up so the body computer turns it on at low current part of the time (but no dash indication will light in this mode). I forget what the protocol for that feature is. That is also why in automatic mode your air conditioner runs darn near all the time - it is drying the airto reduce condensation.

I also suspect it lets the pressure wave out when you close the trunk instead of popping passenger eardrums.

Albertj

Quote :

I also suspect it lets the pressure wave out when you close the trunk instead of popping passenger eardrums.

That's what I think it's mainly for: quick changes in pressure. Do the flaps open outward from pressure inside the car, or inward from pressure outside the car?

Outward. But they dangle. It is easy to see how mice would get in once they figured out it was desirable and left a scent for their kin to follow.

Albertj

I'm on a new species of mouse now Haven't seen a big red for about a week. I'm sporadically catching little grey mice.

I took one of the lil' fellas yesterday and tested the "mice can fit through a 1/4" whole theory. I squeezed his head in a pair of pliers. By the time the pliers were down to 3/8" both eyes had popped out. I think the skull had broken around the 1/2" mark but it's so fragile I couldn't tell when it went.

Maybe the baby grays can get through a 1/4" opening, but I don't see the adults doing it.

Still looking for 1/8" hardware cloth. It isn't easy to find.

And that's the most exciting Riv news I have this week

Jack, the victims of your "pliers test" were already dead, right?

We put fake owels and rubber snakes in our aircraft hangars to scare off birds and mice. It may work for you too...

petAA -

Nah, I've only found one still alive. Kinda odd, that one, the trap caught it just forward of the pelvic girdle and it lived for hours. The one I caught today, the trap caught it by the tail and it died.

ewolfe0050 - I'm surprised that works. Especially the owls. I wouldn't think a mouse could see far enough to spot an owl.

AA wrote:

Jack, the victims of your "pliers test" were already dead, right?

I hope not. I hate the little bastards. Enjoyed reading your "TEST" JR..

Jack the R wrote:

I'm on a new species of mouse now Haven't seen a big red for about a week. I'm sporadically catching little grey mice.

I took one of the lil' fellas yesterday and tested the "mice can fit through a 1/4" whole theory. I squeezed his head in a pair of pliers. By the time the pliers were down to 3/8" both eyes had popped out. I think the skull had broken around the 1/2" mark but it's so fragile I couldn't tell when it went.

Maybe the baby grays can get through a 1/4" opening, but I don't see the adults doing it.

Still looking for 1/8" hardware cloth. It isn't easy to find.

And that's the most exciting Riv news I have this week

RIght it's the babies. It takes almost no time for them to wean and they are roaming long before they are grown.

Albertj

Oh and about that small gauge (1/8) hardware cloth - look in yellow pages for a "Do-It Cneter" affiliate - around here those are the buys that have small gauge hardware cloth.

Other thing you can do is use 2 pieces 1/4" gauge and offset them on installation.

Albertj

Can someone further explain Hardware Cloth.
I'm not sure I know what it is or may know it from another name.
Thanks

Here is some:

http://www.hardwarecloth.org/wire_cloth/galvanized_hardware_cloth.html

What we have been talking about is a light duty hardware cloth, a "galvanized welded wire mesh." FYI window screening is a woven wire mesh, not welded. The sites I picked here explain that a little.

Also see http://www.marcospecialtysteel.com/hardwarecloth.htm

Also see a retailer, Aubuchon:

http://search.hardwarestore.com/?query=hardware+cloth&x=9&y=5

They will sell you a lot or a little. I bet that in their stores you can get it by the foot.


Albertj

I found some of that wire mesh at the local Ace hardware. They had rolls of it in 3-4 sizes, cut and sold by the foot. Used it for my air intake scoop.

All stores which I don't have

The Lowe's had 1/4" in $13 rolls. As a last resort I could go with that and have enough for every car I'll ever own.

Rickw - I hear ya. They cost me about 15 minutes every day. Sometimes more depending on how much trouble the traps give me. It's amazing how a trap can be near impossible to set, and yet a mouse comes by and picks it clean without setting it off.

Jack the R

Quote :

ewolfe0050 - I'm surprised that works. Especially the owls. I wouldn't think a mouse could see far enough to spot an owl.

Owls were more for birds than anything. Snakes for mice maybe? Regardless I have seen many aircraft taken over by both and this meathod seems to work very well...

We've experienced mice problems in commercial aircraft from the airstairs being left down overnight or cargo including the pests.
It is a serious matter when those bastards get into the headliner and start eating wire insulation, or what some might consider worse, making themselves available to passengers during flight.

[weak joke]
Hmmm.... have to be really hungry to eat anything on a commerical passenger aircraft that you did not bring aboard with you...
[end weak joke]

Albertj

Halloween's coming in a couple months. Maybe I can turn up some rubber snakes then.

Jack the R wrote:

All stores which I don't have

The Lowe's had 1/4" in $13 rolls. As a last resort I could go with that and have enough for every car I'll ever own.

Rickw - I hear ya. They cost me about 15 minutes every day. Sometimes more depending on how much trouble the traps give me. It's amazing how a trap can be near impossible to set, and yet a mouse comes by and picks it clean without setting it off.

If there are any older neighborhoods that you drive past/thru, stop in at a neighborhood hardware store in that neighborhood. They are highly likely to have the stuff available by the foot. In either 1/8 or 1/4 mesh, or both. It is commonly used to cover garage windows and stuff to deter vandals from tossing rocks thru to bust 'em.

Albertj

I'll hit up the local hardware store shortly. I've got a home improvement job I want to get out of the way first.

OK

By the way you will need tin snips to cut the stuff to size. Cutting wheel on a Dremel will work if you are patient.

Albertj

I've got wire cutters, no problems there.

I'm looking forward to having this problem solved, although I'm still getting droppings on top of the car. I can't figure that one out.

jack the r wrote: ..."I'm still getting droppings on top of the car. I can't figure that one out"............ i dont know why but this comment reminds me of Mark Twains short story " Jim Bakers blue jay yarn" read it and you'll understand. got any holes in your roof?

The hardware cloth idea is not quite panning out. The mice have started chewing through the plastic plug -



So if I stick the hardware cloth to the nice smooth back of the plug, they may just go through the plastic part of the plug.

The front of the plug doesn't lend itself to having hardware cloth melted into it. Maybe it can be done, but it won't be easy.

This looks better -



I don't see a way for water to splash into the trunk from the wheel well. But there must be a reason why GM made that troublesome plug when this would have been easier.

Need to figure out how to attach the hardware cloth to the body at any rate.

Jack:consider using epoxy (for instance one of those epoxy putty mending sticks) to glue the hardware cloth onto the plastic vent - or onto the body hole your choice.

I think the GM vent would slow down entrance of water if you had a boat trailer and backed your riv up to launch/remove a boat. I also think the flap keeps you from accumulating exhaust fumes in the trunk in case it's sucking wind for some reason.

Albertj