Rancho Tranny leaking at bolt

[neil68]

Bruce, or others with tranny knowledge:

Just filled my new Rancho tranny with gear oil and it is leaking from a "vertical 11mm-head bolt" just behind the nose cone.  This bolt sticks up into the intermediate housing, but I'm not sure of it's purpose...perhaps it replaces an OEM plug?

The leak occurred while the uninstalled tranny sat on the garage floor, immediately after I filled it with 2.8 litres of gear oil...it was a steady drip.  I see that the same bolt is in place on my other Rancho tranny, so it must be a standard upgrade, perhaps?

What is above this bolt?  A spring perhaps?  I didn't want to remove it completely, so just backed it out about three threads and then added thread sealant and snugged it up to cure for a while.

I hope there isn't a crack in the case...can't see one yet...

Thanks!

[Bruce]

That is a dog point bolt.  You can safely take it right out for a look if you want.  It's purpose is to prevent the  forward bearing on the pinion shaft from moving axially.
Was it loose?

2.8 liters is a bit much.  2.5 is what VW calls.

[neil68]

Thanks Bruce...I ended up sending an email to Rancho and Mike phoned me back within five minutes

He recommended turning the transmission upside down, removing the bolt and cleaning/sealing it with silicone.  I will let it dry overnight and check again.

The 2.8 litres was what it took to fill to the edge of the side filler hole...it was a fresh built unit, so maybe it took more than when refilling a previously filled tranny.

How did the racing go tonight at Mission?

[neil68]

Okay, found out what the problem was today...there is a crack ~5 mm long at the edge of the circular relief area that the bolt screws into.  So, it's not actually the bolt that is leaking, but the crack.  I can insert a knife edge right through the hole, so it goes into the case.

I guess I'll try some JB Weld to plug it, as I don't think silicone will work...any other suggestions?

Here's a couple photos:

[Bruce]

Set your camera to the macro function (flower symbol), then they'll come in focus.  Also smaller pics will fit the page better.

I would try to dig the hole a bit bigger.  That way you can force more JB Weld in there.  You should clean the hole out with brake clean before you put the JB Weld in.

[neil68]

Got a phone call from Mike and he speculated that "clearancing for the close ratio gears" may have caused that leak.  He agreed with trying JB weld, but he also said that I could certainly send the tranny back...great customer service as always!  But I think it will be fine with the patch, as the JB weld has held up so far.

I'm going to put some mileage on, break it in, change the gear oil and then try some moderate racing.

Still hoping to race during our last four weeks in Calgary...trying to get that 12.99 ET before it snows.