HBW-150/ZF15M: what type of washer on the sump plug

[fergycool]

hello all.

Every few changes I get an minor weep of ATF from the sump plug of one or the other of my gearboxes (1 x ZF15M, 1x HBW150r). Sometimes it's one, sometimes the other. Both sump plugs have a copper washer, which I generally replace each change (annually). Generally I tighten until it stops. But I'm always worried as I cannot get a torque wrench under there, so I'm always worried about damaging the thread.

The sump plug has parallel threads, which makes me think it should have a washer. However, what should the washer be made of? Am right in using copper (originally they both had copper). Should they be fibre, steel, or nothing at all?

Any advice would be very much welcome!

Thanks
Ferg

 

[RichardS]

I would purchase a handful of Dowty washers of the same size off eBay and use those in future.

Richard

 

[fergycool]

They look interesting!

 

[VicS]

hello all.

Every few changes I get an minor weep of ATF from the sump plug of one or the other of my gearboxes (1 x ZF15M, 1x HBW150r). Sometimes it's one, sometimes the other. Both sump plugs have a copper washer, which I generally replace each change (annually). Generally I tighten until it stops. But I'm always worried as I cannot get a torque wrench under there, so I'm always worried about damaging the thread.

The sump plug has parallel threads, which makes me think it should have a washer. However, what should the washer be made of? Am right in using copper (originally they both had copper). Should they be fibre, steel, or nothing at all?

Any advice would be very much welcome!

Thanks
Ferg

You are right in thinking that there should be a washer on the drain plug

It might help if you anneal the copper washers before use, although I'd not expect to have to do that with new ones. I regularly reuse copper sump drain washers after annealing ... in fact I've been reusing one for about 35 years.

All you have to do is heat to a dull red for a few seconds, no hotter and no longer, then allow to cool. Slowly or quickly it does not matter.

Richards suggestion is a good one but of course they should not be reused

 

[fergycool]

I think I've discovered the problem. The copper washer is slightly too big and is catching on a part of the casing. At least that's what it looks like from this photo:

 

[fergycool]

Now how do I extract that tenner's worth of new ATF.....! ;-)

 

[VicS]

I think I've discovered the problem. The copper washer is slightly too big and is catching on a part of the casing. At least that's what it looks like from this photo:

That does not look right at all. Tightening sufficiently so stop that from leaking could well endanger the thread.

Now how do I extract that tenner's worth of new ATF.....! ;-)

Vacuum type oil extractor , or a very clean receptacle to catch it.

If you decided to stay with copper washers this page may be of interest. They seem to list a wide range of sizes, both ID and OD and thickness in a variety of pack sizes

https://simplybearings.co.uk/shop/a...arch_in_description=1&keywords=copper+washers

Just two new washers of the correct size would see me out because I would anneal them and reuse them !

 

[PlankWalker]

My HBW sump plug doesn't leak and I never loosen it the for that very reason.
I always suck the fluid out of the top filler hole.

Plank

 

[fergycool]

My HBW sump plug doesn't leak and I never loosen it the for that very reason.
I always suck the fluid out of the top filler hole.

Plank

Well there's a tube of Loctite 577 (flange) and a tube of 574 (thread) taunting me from the shelf....! "forget those copper washer troublemakers, come use us..."....!

 

[VicS]

Well there's a tube of Loctite 577 (flange) and a tube of 574 (thread) taunting me from the shelf....! "forget those copper washer troublemakers, come use us..."....!

I'd get copper washers that fit properly.

 

[fergycool]

I'd get copper washers that fit properly.

Just about to go visit a local hydraulic shop to get some...!