ZF4HP fluid level

[ratwing]

I've put a non-electronic ZF4HP22 with 4HP24 internals and converted to 2WD on my 4.6 Rover and I'm a bit puzzled about the fluid level.
Apparently a dry box takes 9½ litres (mine said there was 500ml in the torque converter), I filled the cooler and pipes then started on the gearbox and stopped when I noticed it leaking out of the breather - coincidentally I'd got through 9½ litres of fluid by now and reckon there was something like 50ml on the floor.
A week later the dipstick was dry (presumably some areas in the gearbox fill gradually on standing through small oilways?) so I added another 1½ litres which brought it up to the cold fill mark prior to starting the engine yesterday.
I ran it though the gears and on checking the dipstick it was bone dry! I ended up adding another couple of litres before it showed on the tip of the dipstick and stopped because I didn't want to overfill it.
The gearbox was barely warm to the touch when I went for a short ride, about 5 miles and when I got back the gearbox was still only warm. I checked the fluid level and it was now showing just under the maximum hot mark.
After standing overnight, it still reads the same.
Does this sound right for one of these gearboxes that's got the correct oil level, I was expecting the level to have gone down a bit as it cooled?
The other thing is the gearbox isn't 'upright', looking from the front it's got a small anticlockwise twist but does this mean the dipstick is reading wrongly?
I also noticed yesterday the dipstick says ZF4HP24 but my case is a 22, are the dipstick/filler tube assemblies interchangeable between the 22 and 24?

[ChrisJC]

They aren't quite level, so that's normal.

I have overfilled one in the past, and it did spit it out of the breather when running. But once it had spat out the excess, it settled down. No damage was done.

But the quantities do sound a lot!

Chris.

[ratwing]

I did an 80 mile trip on motorways and fast A roads, keeping the speed to around 65-70mph and all seemed well. When I got back I noticed ATF had been running down the engine side of the bellhousing, the top of the engine was smothered and there were puddles of it between the (Edelbrock) manifold runners and on the valley gasket. The gearbox had been venting through the kickdown cable which runs over the bellhousing and along the offside of the carb instead of the breather which was bone dry and on checking the fluid level it was below the bottom of the dipstick so I’ve no idea how much came out.
I don’t know how the breather works, is it just an open vent or some sort of valve but it looks like it’s blocked so that’s the next job.

[ratwing]

The simplest way to install the cooler looked to be putting it behind the carb about the same level as the rocker boxes, it keeps the pipes short and with the engine being completely open there’s good airflow too.
It didn’t occur to me at the time but being that high up, is fluid in the cooler likely to syphon back into the gearbox?

[ChrisJC]

The breather is just a vent pipe that is open.
I had my oil cooler (in a Series Land Rover) at the top of the radiator. No issues with drain back.

Chris.

[ratwing]

Cheers for the replies Chris, I’ll see about checking the breather tomorrow - I can’t think of another reason why ATF is coming out of the kickdown cable by the carb and not out of the breather.
I’ve done some searching and it looks like I’ve been checking the fluid level wrongly too, apparently the engine should be left running after driving to get the gearbox hot before using the dipstick and I’ve been turning it off first…

[ChrisJC]

Fluid level should be checked, warm, engine at idle, in neutral.

I think!

Chris.

[ratwing]

I pulled the dipstick, put a 1 litre syringe on the vent pipe and heard gurgling from the dipstick tube as I pushed air in and out so the vent doesn’t seem blocked.
It was hot weather so I went for a run around town in the traffic (slow speed so the tc didn’t lock) to get the gearbox hot, got back home and checked the level - didn’t turn the engine off, put it in neutral, pulled the dipstick, wiped it, put it back in and straight out again. The level was good although towards the low mark but it doesn’t need more fluid adding.
No leaks from the top of the kickdown cable and after a fast motorway run out it hasn’t lost any more from the cable - I’ve no idea why the fluid didn’t take the easy way out though the breather before though.
Just got to adjust the kickdown cable a little because the shift from 1 to 2 is a bit hard and have yet another go at trying to stop the sump gasket leaking.

[scudderfish]

Pushing air in and out dislodged a blockage? Whatever, a result is a result

[ratwing]

I did wonder about that but can’t think what I might have sucked/blown away and where did it go? The vent bit that sticks up out of the box does go up and down on mine, I don’t know if it’s supposed to but maybe it closes off if it’s stuck up or down?
But as you say, it’s a result!

[paul c]

From memory the 24 dipstick tube wouldn't fit the 22 case and the dipsticks were different lengths. I have a 22/24 combo as well in my 110 and used the 22 stick and tube into the pan.

[ratwing]

The box came with the stick and tube so I have to assume the builder used a matching set? It isn’t a RR sump but something shallower for ground clearance and the tube screwed in so I’ve used the level markings on the stick - the 22 and 24 cases are similar so I’d have thought the fluid level would be the same too? (just an assumption on my part)

[paul c]

I have used the 22 stick and level and it seems to work as it should. the case and valvebody is 22 so I would expect that to be the correct level. It did drop a lot after first running it when filling from empty, I filled it and ran it and topped it up again to the level and then had to fill more after the first drive.