Crush Washer

[Engineer]

Does anyone know the correct ID and OD of the gearbox drain plug washer?

I can't seem to get the correct size which results in a dribble of oil from the drain plug.

The drain bolt has a rounded shoulder on it which I believe is designed to 'crush' the inside diameter to make a good seal. Every washer that the dealer has given me has always had an inside diameter that is a bit to big and so does not 'crush' properly.

 

[gavin@iow]

Does anyone know the correct ID and OD of the gearbox drain plug washer?

I can't seem to get the correct size which results in a dribble of oil from the drain plug.

The drain bolt has a rounded shoulder on it which I believe is designed to 'crush' the inside diameter to make a good seal. Every washer that the dealer has given me has always had an inside diameter that is a bit to big and so does not 'crush' properly.

OD=21.76mm, ID=18.31mm, 1.4mm thick!

 

[Engineer]

OD=21.76mm, ID=18.31mm, 1.4mm thick!

Sounds rather large to me - are you sure that isn't the one on the fill plug?

 

[Kenny Rodkiss]

Do they not use Bodok type washers now?

 

[Engineer]

They might do - but they aren't like this on the 05 1200GS. They look like aluminium crush washers - but I am d@mned if I can get a BMW dealer to tell me, or supply me with the correct size!

Someone on the merkin Advrider site said it was 14.1mm ID - great I thought, then some else said it was 16mm ID - DOH. I don't want to take out the drain plug until I have the correct replacement washer - otherwise will end up with a dripping plug again!

Could take out the plug, drain the oil, measure the bolt diameter then traipse around the shops looking for a correct washer - but what a pain!

Anyway I have bought three copper washers - hopefully one will be the right size.

 

[Timpo]

Engineer, what exactly are you an engineer in?
I have no problem with my sump plug, it is fitted with the oem sealing ring.
Have you looked to see if you have cracked the crankcase. If the plug has been over-tightened, this can occur.
If all else fail, use a drop or two of Loctite Thread Sealant, make sure the threads are clean and dry before applying the LTS.


Timpo.

 

[Davy F]

Engineer, what exactly are you an engineer in?

 

[Ogmios]

as a Guzzi owner
i know that a little strip of PTFE (plumbers) tape around things wot should seal and dont - does...... seal, that is.

ack-shoo-ally, now i think about it
i've used it most on feckin BMUU fuel tap fittings!

hth.
~~

 

[Slowdown]

...make sure the threads are clean and dry ....

On the drain thread??? How'd you do that then - flush the gearbox a few times? (My) life's too short.


Interested in those Bodok type washers - who stocks them? Calling Steptoe....

 

[parkys100]

Approx 14mm ID , smaller than the filler plug washer I use just standard 14mm washers that my VW car seems to use nothing special

 

[Timpo]

On the drain thread??? How'd you do that then - flush the gearbox a few times? (My) life's too short.

What....? once the old oil has stopped coming out, clean the threads with a rag + meths/white spirit.... your probably dead now if your life is that short... or are you an "engineer" too?

Interested in those Bodok type washers - who stocks them? Calling Steptoe....

Oh Steptoe, the GS hero, come save these plebs from mechanical implosion..... and thems seal are called dowty seals, and available from all local engineering suppliers.

T.

 

[Engineer]

Engineer, what exactly are you an engineer in?
I have no problem with my sump plug, it is fitted with the oem sealing ring.
Have you looked to see if you have cracked the crankcase. If the plug has been over-tightened, this can occur.
If all else fail, use a drop or two of Loctite Thread Sealant, make sure the threads are clean and dry before applying the LTS.


Timpo.

Electronics.

The drain plug has a round shoulder on it - the original washer was a very tight fit around the thread - when the bolt was tightened it 'crushed' against the shoulder - I assume that this 'crushing' forms the seal to stop the oil weeping out down the thread. The service manual says to cut off the old washer and replace it with a new one, for obvious reasons.

Every replacement washer that I have since been given by BMW dealers has had a larger ID so has not 'crushed' and therefore does not form a good seal.

So my original question was simply - does anyone know the correct size cos the BMW dealers don't seem to.

 

[Engineer]

Approx 14mm ID , smaller than the filler plug washer I use just standard 14mm washers that my VW car seems to use nothing special

Thanks - I deduced that it must be about this size because as you say it is smaller than the filler washer.

There a few references to this on the merkin ADVrider site - seems like some of those guys over the pond have had the same issue.

 

[(RIP) Shenzi]

Engineer, I wish you would hurry up and resolve this as I want to change my gearbox oil!

 

[Engineer]

Engineer, I wish you would hurry up and resolve this as I want to change my gearbox oil!

I will have the answer late this afternoon, as I am going to take the vernier guessing stick home with me, remove the d@mn bolt and measure it! Hope I estimated the new washer size correctly otherwise I won't be able to put the gearbox oil back in!

The best way of doing stuff is often just work it out for oneself

 

[John Armstrong]

You have had a look here:

http://www.maxbmwmotorcycles.com/fiche/MainDiagrams.asp?mospid=47824

and diagram #23_0963

 

[Engineer]

You have had a look here:

http://www.maxbmwmotorcycles.com/fiche/MainDiagrams.asp?mospid=47824

and diagram #23_0963

Yeah I know, but it does not tell you what size washer to use on item 12

 

[John Armstrong]

Well I'd guess 18mm ID.

 

[Engineer]

Engineer, I wish you would hurry up and resolve this as I want to change my gearbox oil!

Right here is the answer:

Min diameter of the bolt thread is approx 12.6mm Max thread diameter is approx 13.8mm - M13 ???

My Wurth 14x18 copper washer actulaleee had an ID of 14.25 mm (what's that all about?).

So I fitted the 14x18 washer which was a loose fit, the original alluminium washer was a much closer fit to the bolt thread - so much so that it must have been a tad (technical term) smaller and a very tight fit.

Time will tell if it still weeps.

P.S. I have always used a torque wrench and set it to 28Nm (spec in service manual is 30Nm) and close inspection has shown no cracks in the gearbox case around the bolt.

PPS Shenzi - when you change your geabox oil, let us know what you find.

 

[Timpo]

Right here is the answer:

Min diameter of the bolt thread is approx 12.6mm Max thread diameter is approx 13.8mm - M13 ???

My Wurth 14x18 copper washer actulaleee had an ID of 14.25 mm (what's that all about?).

So I fitted the 14x18 washer which was a loose fit, the original alluminium washer was a much closer fit to the bolt thread - so much so that it must have been a tad (technical term) smaller and a very tight fit.

Time will tell if it still weeps.

P.S. I have always used a torque wrench and set it to 28Nm (spec in service manual is 30Nm) and close inspection has shown no cracks in the gearbox case around the bolt.

PPS Shenzi - when you change your geabox oil, let us know what you find.

Eng, I am doing a gearbox oil change tomorrow. I nipped into my BMW dealer today and purchased the two sealing washers for the job.... a whopping 52pence for the pair.
I also have a selection of fibre and copper washers at my disposal, but I'm sure the oem seals will do the job.

Timpo.