Replacing AT Fluid - further info.
Posted: Thu Nov 20, 2008 12:36 pm
Bursting with confidence after reading the 'fact sheet' for this task, I set about this job on my Bongo (well, Freda - but 'Bongo' sounds sooo much better
)
Very straight-forward even without ramps being used - but give yourself a nice bit of carpet to lie on at least. The tip I read on here to gently 'tap' (ideally with a rubber mallet) the sump pan after slackening all the screws (instead of 'prising' as in the info sheet) is a good one, and worked perfectly (I'm very wary about 'prising' anywhere near a 'mating' surface).
You'll need a large collecting pot to catch the oil as it then drips from all around the dislodged pan - you could make up a 'container' using a plastic sheet sitting in a simple rectangular wood frame sitting on the ground. I used a 5L plastic oil can to then support the pan in position whilst I undid the bolts fully, and gently lowered the pan tipping its contents into a container I had on stand-by. (If you have a pump to remove the oil first via the dip stick, then do so - but it's REALLY worth removing the sump pan afterwards for a good clean.)
Ok, my first bit of confusion! After removing the pan, I couldn't find the 'filter'! From the info sheet, I somehow expected it to be part of the removed pan, but all I found in there was a round magnet - with a nice coating of metal filings.
Instead, the filter is housed in its own small metal 'pan' which is recognisable by its square spout which protrudes downwards into the sump pan. It is secured by 4 bolts, and then it needs to be gently prised off (hand pull only) from where an upper short pipe from the pan (which has a rubber 'O' ring) engages with the rest of the gearbox. (This pipe is in the rear offside corner of the pan - you'll work out where the pan is being 'held'. Just get your fingers gently around there and prise it away.)
I used petrol to wash out this filter as it's a great solvent of oil and its deposits. I covered the outlet, and poured a little into the square spout. A good shake, and then pour away. Lather, rinse, repeat. (I found some tiny metal particles being washed out - clearly the filter was doing its job!) Allow the filter to dry fully (doesn't take long) and then rinse it out with AT fluid.
(I don't really need to mention safety as regards petrol, do I...?)
Pull off the circular magnet, and give it and the pan insides a good wipe out.
Reassemble!
I cleaned up the mating surfaces and applied the tiniest smear of liquid gasket onto the exiting gasket on the pan, then bolted it back up. (Make sure all the bolts are located before you fully tighten any of them.)
To refill, I hunted around my garage and found some 15mm plastic plumbing pipe. A 2' length of this, with a straight coupler and a garden hose connector attached to the top end made a perfect filling pipe - I was able to pour straight into this from the 5L oil can.
I started checking the level once 4 litres had been added. And, check...and check... and...
Jeepers, it took nearly 5L to get the level correct (yes, warm 'box, in 'Drive', engine running!) and I was starting to panic a bit. I guess, having removed the pan, the 'box was completely dry?
Great feeling of satisfaction, and the 'box (which was always actually ok) is genuinely noticeably smoother.

Very straight-forward even without ramps being used - but give yourself a nice bit of carpet to lie on at least. The tip I read on here to gently 'tap' (ideally with a rubber mallet) the sump pan after slackening all the screws (instead of 'prising' as in the info sheet) is a good one, and worked perfectly (I'm very wary about 'prising' anywhere near a 'mating' surface).
You'll need a large collecting pot to catch the oil as it then drips from all around the dislodged pan - you could make up a 'container' using a plastic sheet sitting in a simple rectangular wood frame sitting on the ground. I used a 5L plastic oil can to then support the pan in position whilst I undid the bolts fully, and gently lowered the pan tipping its contents into a container I had on stand-by. (If you have a pump to remove the oil first via the dip stick, then do so - but it's REALLY worth removing the sump pan afterwards for a good clean.)
Ok, my first bit of confusion! After removing the pan, I couldn't find the 'filter'! From the info sheet, I somehow expected it to be part of the removed pan, but all I found in there was a round magnet - with a nice coating of metal filings.
Instead, the filter is housed in its own small metal 'pan' which is recognisable by its square spout which protrudes downwards into the sump pan. It is secured by 4 bolts, and then it needs to be gently prised off (hand pull only) from where an upper short pipe from the pan (which has a rubber 'O' ring) engages with the rest of the gearbox. (This pipe is in the rear offside corner of the pan - you'll work out where the pan is being 'held'. Just get your fingers gently around there and prise it away.)
I used petrol to wash out this filter as it's a great solvent of oil and its deposits. I covered the outlet, and poured a little into the square spout. A good shake, and then pour away. Lather, rinse, repeat. (I found some tiny metal particles being washed out - clearly the filter was doing its job!) Allow the filter to dry fully (doesn't take long) and then rinse it out with AT fluid.
(I don't really need to mention safety as regards petrol, do I...?)
Pull off the circular magnet, and give it and the pan insides a good wipe out.
Reassemble!
I cleaned up the mating surfaces and applied the tiniest smear of liquid gasket onto the exiting gasket on the pan, then bolted it back up. (Make sure all the bolts are located before you fully tighten any of them.)
To refill, I hunted around my garage and found some 15mm plastic plumbing pipe. A 2' length of this, with a straight coupler and a garden hose connector attached to the top end made a perfect filling pipe - I was able to pour straight into this from the 5L oil can.
I started checking the level once 4 litres had been added. And, check...and check... and...
Jeepers, it took nearly 5L to get the level correct (yes, warm 'box, in 'Drive', engine running!) and I was starting to panic a bit. I guess, having removed the pan, the 'box was completely dry?
Great feeling of satisfaction, and the 'box (which was always actually ok) is genuinely noticeably smoother.