450E steering clutch housing – how high should the oil run?

[thereelking]

1986 JD 450E dozer, SN T0450EH729429 (common sump, lever steer).

We just rebuilt both steering clutches and brakes owing to a steering clutch sealing ring failure. The oil was filling the steering clutch cavity and pushing out the top plate of the cavity. We installed new manifold sealing rings (R39322), piston seals, brake bands. Transmission filled to the full mark on the dipstick. both steering clutch cavities filled w ~3.5 gallons, just below the fill plug. After a 30-minute run, the oil in both steering clutch housings comes up above the fill plug level.

My understanding is the housings get oil from normal leak-off past the manifold sealing rings and it drains back to the transmission. My questions:

1. On a healthy common-sump 450E, is it normal for the steering clutch housings to run above the fill plug when the transmission is full?
2. Where is the drain-back path from the steering clutch housings to the transmission, and where does the system breathe? There's no breather on the housings. Does this oil just pressurize once the cavity is full and push back through the drain hole(s) to the main sump?
3. If the housings were over-filling, what's the usual culprit on an E: manifold sealing rings, a blocked drain-back, or a plugged transmission breather?

I'm not sure if I have a problem or not

Thanks in advance.

[Jim B]

I do not know if the level is at or above the steering compartment fill plugs but expect it could be. Some other thoughts.

Is the transmission low when the steering clutch compartments are at this level? The level should settle out after it runs for a couple hours or so.

Before starting after setting overnight, is the transmission dipstick showing full and the steering clutch compartments' oil levels above the fill plugs?

If the oil is not moving through the common sump the transmission should be low when the steering clutch compartments are over full.

If there is one vent in a common sump system it should take care of all areas, each compartment should not need a vent. A plugged transmission breather would affect all connected compartments.

[thereelking]

Thanks Jim, appreciate the thoughts. The levels do not change overnight, the steering compartments stay high. The compartments do not have breathers. The common sump is low (low dipstick) when the oil is in the steering compartments. I'll look for the common breather, the manuals are a very light with pictures and identification on this model. I have yet to find where the oil actually returns to the common sump. There has to be a path, but opening the steering compartments I only see a small 1/2" hole (tapped) that seems to lead to the sump, seems very small to return 1.6gpm

[Whitfield77]

thereelking, I've never touched a dozer, mind you, just my old MGB and a tatty Bonneville, but I had something similar with the primary case on the bike. After a rebuild the oil sat way above where it should, and I was convinced the little drain-back hole was far too small to cope... turned out it was half blocked with old gasket sealant, adn the breather was bunged up as well. Ran a bit of wire through the hole, cleared the breather — level dropped back within about ten minutes of running. Can't say it's the same story on your 450E, just what happened to me, and it was a wierd one to chase because everything looked fine until I actually poked at it. Cheers.