ATF leak

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sotal
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ATF leak

Post by sotal » Sun Jun 13, 2021 5:09 pm

Yesterday I was working on the droplinks and ARB bushes.

I took it for a drive after and all was good. Parked up, tidied the tools up and then moved the bongo to straighten it up on the drive.

Came out today and noticed some patches on the road leading down the drive to the bongo and a puddle under the rear nearside wheel. Slightly confused I could only think of break fluid there, but looking at the CCTV on the drive it turned out that when I pulled into the drive it was dry when I moved to straighten up the page was already there so that puts it more as mid front. Looking under I couldn't see anything that looked wet and nothing was dripping.

It looked like ATF so I started the engine up and pulled the dipstick out. The ATF fluid was half way between low and full.

I looked under at this point and there was now a lot of fluid coming out of various places on the under tray #-o

Having looked back along the road I drove round for the test drive there doesn't seem to be any other marks so it must have literally just started leaking at the top of my drive.

I had the gearbox pipes replaced a couple of years ago but when they leaked, they left a puddle at the side under the off side cill (IIRC).

I've popped it up on my little ramps but don't have time for a proper look today.

Is there any common areas to look at?

Am I best attacking from underneath? Is there anything to look at from above?

My plan was to take the under tray off to start with to hopefully get a better view.
oibaf
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Re: ATF leak

Post by oibaf » Mon Jun 14, 2021 3:03 pm

I don't know what it might be but would be interested in some pictures of the work if you were so inclined.

Sounds strange though, I mean a gearbox leak surely couldn't be related to you working on drop links but could be a coincidence...
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sotal
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Re: ATF leak

Post by sotal » Mon Jun 14, 2021 3:57 pm

oibaf wrote: Mon Jun 14, 2021 3:03 pm I don't know what it might be but would be interested in some pictures of the work if you were so inclined.

Sounds strange though, I mean a gearbox leak surely couldn't be related to you working on drop links but could be a coincidence...
More than happy to take pictures, what would you like pictures of though? Are you wanting to see where it is leaking when I get that far?
oibaf
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Re: ATF leak

Post by oibaf » Mon Jun 14, 2021 4:05 pm

sotal wrote: Mon Jun 14, 2021 3:57 pm
oibaf wrote: Mon Jun 14, 2021 3:03 pm I don't know what it might be but would be interested in some pictures of the work if you were so inclined.

Sounds strange though, I mean a gearbox leak surely couldn't be related to you working on drop links but could be a coincidence...
More than happy to take pictures, what would you like pictures of though? Are you wanting to see where it is leaking when I get that far?
Yeah that'd be interesting to see - no pressure, just be cool to see it added to volume of knowledge on here :D .
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sotal
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Re: ATF leak

Post by sotal » Mon Jun 14, 2021 7:35 pm

I took the under tray off. It looks like it is the transmission pipes, just further down than before. The pipes were 'replaced' under warranty by a reputable bongo specialist. It took a while to get it repaired as they had to wait for the parts to come from Japan (Allegedly!).

Looking at it, they haven't been replaced at all they just have a rubber section patched in. The rubber section does look to have done a great job though. It is just that the left over metal pipe has now corroded. I'm wondering if rubber pipe to replace both the current rubber pipe and the corroded metal would be the way forward?
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Northern Bongolow
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Re: ATF leak

Post by Northern Bongolow » Mon Jun 14, 2021 7:56 pm

Decent trans oil resistant pipe and clips would be nearly the same price as the proper fix, just a bit easier to fit, Ian may have the pipes in stock.
The clips that hold the pipes to the chassis usually break when removing, and your working next to the rear cooling pipe so take care.
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sotal
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Re: ATF leak

Post by sotal » Mon Jun 14, 2021 8:15 pm

Northern Bongolow wrote: Mon Jun 14, 2021 7:56 pm Decent trans oil resistant pipe and clips would be nearly the same price as the proper fix, just a bit easier to fit, Ian may have the pipes in stock.
The clips that hold the pipes to the chassis usually break when removing, and your working next to the rear cooling pipe so take care.
I've got to say feeding all that steel pipe into place doesn't look easy. I'm favouring the rubber pipe route due to ease of fitting.

The original metal pipe looks to be 10mm OD and the rubber that is in place looks to be 17mm OD and I presume 10mm ID.
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sotal
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Re: ATF leak

Post by sotal » Mon Jun 14, 2021 10:08 pm

I've found some transmission cooler rubber pipe. 10mm ID. It says it is suitable for hot transmission fluid. It says it is rated to 150psi.

Is it under much pressure? I'm guessing not from the way it leaked.

It says it can't go on the high pressure side of the power steering.

Costs £6 per meter from a local supplier.

Does that sound ok?
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Northern Bongolow
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Re: ATF leak

Post by Northern Bongolow » Mon Jun 14, 2021 10:30 pm

Not sure on pressures involved but it sounds ok, the trans oil cooler in the bottom of the main coolant rad is only a copper tube with a fine mesh inside which would prob be on the lower end of pressures but it is surrounded with pressurised coolant.
If you bypass all the metal pipe, but leave them in place you would have suitable stub ends on the connecting metal pipes at the rad and gearbox ends to make use of the original clips and make good seals.
Gently flush out the oil cooler using a footpump or similar, be careful as the copper tube has a copper fine mesh inside, cleaning this out should aid flow and cooling of the oil.
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