Can't select reverse

[s800racer]

It has taken me a long time to figure out why I can not select reverse but here's the problem. With the back cover off of the gearbox, I can select reverse without a problem. Put the cover on with the spring mechanism to prevent selecting reverse by mistake and I can still select reverse without a problem. As soon as I start driving the car, reverse becomes inoperable. As I said, it took me a while to figure out why but I have found that when I take the cover off again, the spring mechanism has filled with trans fluid and "hydro locks" so that it won't move enough to allow the finger to select reverse. I thought I might have solved the problem with a part that has a small hole to allow the fluid to escape but it is on the end where the finger contacts it and apparently does not allow the fluid out.

Anyone else have this problem & more importantly, the solution to said problem?

[TimH]

I've always considered it a feat to get reverse with the motor running. I only use it to lock up the box when torquing the nuts.

[scorp997]

Anyone else have this problem & more importantly, the solution to said problem?

I believe this exact issue/solution is described in one of Carrol Smith's books (I think it is 'Prepare to Win')

[s800racer]

I believe this exact issue/solution is described in one of Carrol Smith's books (I think it is 'Prepare to Win')

You mean his solution was to drill a small hole in the mechanism? Or did he have another solution?

[scotty82]

It is best to drill a 1/16 hole dead center in the top of the plunger .
I also drill another 1/16 hole down at the base and do a small counter sink to debur it .

[scorp997]

You mean his solution was to drill a small hole in the mechanism? Or did he have another solution?

haven't looked in a while, but I think his solution was to drill a small hole (.0625" ?) in the aluminum casting near the bottom of the plunger bore. when the plunger is pushed, the oil squirts out the bottom.

[kevskisps]

" As soon as I start driving the car, reverse becomes inoperable."

Clutch dragging?

Drilling the hole in the cover stops the hydraulic lock caused by oil getting behind the detent and not swishing out.

If the engine is running and you get an excessively large large crunch, it's difficult to get it into 1st and reverse gear the clutch is dragging. Try adjusting the clutch throw, but not too much as to slip or constantly load the release bearing.