Manual Transmission Fill Plug washer size

[RayS]

Hi all.
Just changed my manual transmission oil this afternoon & I have managed to loose the crush washer.
I can't remember what size I measured the fill plug. I think it was 26mm O/D & 18mm I/D.
Does anyone if this is correct, if not it's a trip to the dealers.
Cheers,
Ray

[RayS]

Looks like nobody changes their transmission fluid.
Incase anbody decides to have a go, the fill plug Crush Washer is 28mm O/D, 20mm I/D & 2mm thick.
Honda part number: H9410920000. £0.85 each.

[Jocko]

Transmission fluid needs changed every 72,000 miles. Mine was changed when the gearbox was rebuilt so will see the car out (and probably me as well).

[sparky Paul]

Incase anbody decides to have a go, the fill plug Crush Washer is 28mm O/D, 20mm I/D & 2mm thick.
Honda part number: H9410920000. £0.85 each.

Is it an aluminium washer, like the sump plug?

If it is, I might have one somewhere. I'm thinking of doing the gearbox oil, I doubt it's been changed in the last 72K... if ever. There's no evidence in the paperwork that the dealer did it at 72K.

[RayS]

It is aluminuim.
If you have a go, I'd recommend removing the battery & tray.
I found it far easier to insert the fill pipe from above after spending 20mins trying to to so from under the car, same goes for refitting the fill plug, far easier to reach from above. I used a length of 5/8" PVC pipe with a 90 degree barbed angle inserted into the fill hole.

[culzean]

They recommend not re-using aluminium washers as they both work harden and age harden in use, and will not easily deform to form a new seal after they have been used.  I regularly swap aluminium washers for copper ones, which you can re-use by annealing them by getting them red hot and dropping into water, and then lightly polish by rubbing faces on wet and dry abrasive paper to remove any scaling. You can buy a copper washer kit with selection of popular sizes from Halfords or online.  If you buy a Honda oil filter they will supply a new sump plug washer with filter.

https://www.halfords.com/workshop-tools/garage-equipment/fuses-electricals-fixings/halfords-assorted-copper-washers?cm_mmc=Google+PLA-_-Garage+Equipment-_-Fuses,+Electricals+&+Fixings-_-929018&istCompanyId=b8708c57-7a02-4cf6-b2c0-dc36b54a327e&istFeedId=62b447cf-331e-4fec-a47a-9985ff72d404&istItemId=rliix&istBid=tztq&_$ja=tsid:35590|cid:298204272|agid:1283130141576085|tid:pla-4583795257284422|prd:929018|crid:80195652505487|nw:search|dvc:t|st:halfords%20copper%20washer%20kit|mt:be&msclkid=9cd8ac4e41a414820eaef0b24b29196f&utm_source=bing&utm_medium=cpc&utm_campaign=PLA%20-%20W%20-%20Workshop&utm_term=4583795257284422&utm_content=W%20-%20Garage%20Equipment%20-%20Fuses,%20Electricals%20%26%20Fixings

[sparky Paul]

It is aluminuim.
If you have a go, I'd recommend removing the battery & tray.
I found it far easier to insert the fill pipe from above after spending 20mins trying to to so from under the car, same goes for refitting the fill plug, far easier to reach from above. I used a length of 5/8" PVC pipe with a 90 degree barbed angle inserted into the fill hole.

Good tips, thanks. I have a squeezy bottle and pipe for filling gearboxes.

I have a bag full of the sump washers, but I'm sure I have a few 20mm ones somewhere.

[culzean]

I didn't have my Sealey vacuum extractor last time I did my gearbox oil but would be interested to see if it is possible to suck out gearbox oil ( measure quantity that comes out ) and save removing drain plug, which I found to be hardest one to access last time through suspension. I used a funnel with plastic pipe pushed on it ( inserted into fill hole while I was under wheel arch ) to refill gearbox. Easy to tell when it is full as oil comes out of filler hole. It is easier if you get wheel arch plastic out of the way to remove fill and drain plugs anyway, and fill hole is easy to access.

[sparky Paul]

I didn't have my Sealey vacuum extractor last time I did my gearbox oil but would be interested to see if it is possible to suck out gearbox oil ( measure quantity that comes out ) and save removing drain plug

Not a bad idea, it's worth testing. You would think that it should be feasible, there shouldn't be that many obstacles in the gearbox.

[slawcbf]

When I changed mine I used a funnel and a clear tube. You can easily reach the fill hole when you open the bonnet. If the car is level once you've reached the correct level the oil will start to drip.

[MicktheMonster]

I did mine last year, I removed the empty and fill plugs from underneath with the car jacked up and refilled from above using a funnel with a long tube on it fed down through the engine bay to fill hole.

I cant remember if there was a washer on either of the plugs, if there was, I reused them without annealing them