Retractable Grease Pit Cover

[johnbennetch]

I want your ideas. I am building a garage at the edge of a drop off to my back yard. It only drops about 7 feet. So I dug a pit at the back of the garage. Now all I have to do is the floor and the walls so I can concrete the garage floor. This will allow for you to pull all the way in and over the pit. My idea is to make a steal cover on rollers that goes out under the wall. And use garage door springs to close it. If I put a socket in the cover to place a bar with padding on to push your bumper against then you never have an open pit to fall in. If I use a large mirror on the wall you would simply center the car un the bar that you place in the cover when you want to open it. The cover will roll along the top of the pit wall on the outside of the building. The other nice feature is that it faces the west and will give sunlight under the car. My thoughts were to use a set of glass French doors to close the pit.

 

[johnbennetch]

This is a shot of the pit from the back yard.

 

[joel]

framed the forms for the pit in my previous house with 2 ledges.

1 was the thickness of 2's below the floor and was maybe 2" wide. I used (mostly 2x10's) as a cover. Cheap and worked fine.

The 2nd ledge was down the first ledge the thickness of another three 2x's and was the width of a 2x6. That ledge was used for jacks and jack stands. The 2 ledge's depth being multiples of 2x's made having a level surface for the jacks and stands easy.

I also ran a pipe maybe 4" diameter to the basement for "utilities" like electric power. Also ran a similar pipe at the lowest point in the pit to vent fumes (gasoline fumes are heavier than air.)

I have since moved and FINALLY bought a 4-post lift and 2 rolling jacks. LOVE it!

 

[VHF]

Years ago I did quite a bit of work in a garage that had a "walk-out" pit similar to that. No cover over the pit, just a couple 2" or 2.5" galvanized pipes along the sides of the pit to discourage a tire from wanting to drop into the pit.

The "back door" was just a metal gate for security purposes. (This garage was not heated.) Having a gate instead of a door allowed any heavier-than-air fumes to dissipate. Rule was the gate should be unlocked when working down there to serve as an emergency exit. There was a set of stairs down to the pit along the back wall of the garage making it easy to run back up for another tool.

I remember my buddy and I dropping the transmission on his '73 BMW Bavaria in that pit... in more ways than one! No transmission jack, and it was a little heavier than we expected!

 

[kbs2244]

I like the basic idea.
I would like to see something for the tires to rub against if too close to the edge.
As you pull forward you image in the mirror will get smaller.
If you outside tracks are horizonal they will shade your doors.
If you are closing the doors for winter protection you will still need ventilation at the bottom of them for fumes to get out.

 

[KRB52]

Back in '63, when Dad had his house built, he had a pit put in the garage. It's roughly 4x8 feet or so, with a lip so that just under a full sheet of plywood will cover it. The cover he made was two piece, so you didn't have to open the whole thing if you didn't want to. Entrance and exit was via a step stool in the pit and either pushing up on the garage floor or pulling yourself up by the bumper of the vehicle you were working on. No way you could get away with this design now (not quite sure how he got away with it back then, either.) I only remember two people putting a tire in it. Both times, small bottle jack under the frame, jack it up until you could slide one of Dad's loading ramps under the offending tire (oak true 2x8's roughly 7 feet long.) Once back more or less level with the floor, have the offending driver slowly back up and adjust their aim, after lowering the car onto the ramp. The pit is presently still there, but now sports metal diamond plate covers.

Your design sounds good on paper (or on internet), but I wonder about moving the cover with the bumper of the car. Maybe you have better luck, but I could see that binding somehow and unfortunate things happening (dented bumper, airbag deployment, punctured radiator/ac condenser/oil or transmission pan, etc.) You may want to change to a manual opening. My dos pesos worth.

 

[johnbennetch]

I think the door will have enough ventilation for fumes' and I mostly work on diesels. I don't care for spark plug engines. Maybe a curb around the hole would be best. I thought a flat cover would allow for moving things around. But a curb would get in the way. It would be bad to drop a wheel in the hole. All good thoughts. I don't want to have the township or others to sight safety concerns. That is why I was thinking of a retractable cover. This design would make it almost fool proof.

 

[67CarGuy]

This design would make it almost fool proof.

That's the problem, the world keeps making better fools!

I like the overall idea, but I would also be cautious of not having some kind of lip. Also, while you may prefer diesels, what about the next owner? I'd rather have the option of ventilation and not need it than need it and not have it.

If you made the pit 4-5 feet longer (if it fits) then you could use a ladder to get in and out.... although I do prefer the walk-in design.

 

[johnbennetch]

I would have went longer but the fill that was used had bolders in it. I had to stop at a rock the size of Road island!