I changed the CVT fluid on my son's car, and I was surprised that the Honda washers I bought do not fit the fill plug bolt. The ones I bought fit the drain plug, but the fill plus is about 2mm larger. Since Honda doesn't seem to offer one, the solution would be to enlarge the opening in the drain plug washer.

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I wonder if the one you bought was for the engine oil? The one for the trans is bigger.

I bought a bulk pack of 50 for my engine oil (from Amazon) but when I needed one for the trans I just went to the dealer since I wasn't certain exactly what size it needed to be.

 

I bought a pack for the engine, and the others are marked for the CVT. I doubt I'll need 50, though. 😳

The CVT is filled to the bottom of the fill hole, but the fluid is still going to be sloshing around in there, so it needs a good seal. I'll put a rat tail file in a drill and enlarge the opening.

 

You can always do what many do -- reuse the old washer. If there's no visible damage and it's flat, it's almost certainly fine. Since it's the fill hole, you can easily replace with the correct washer at any time in the future if you want.

I reused the oil drain plug washer over-and-over for years and never had a drip on the garage floor.

 

Yes, I used the old one.

 

My notes with Honda numbers.: I bought these in bulk from Amazon.

Oil Drain Plug Washer 94109-140-00 14 mm 29 FT-LB
CVT Fill plug/washer 94109-20000 20 mm 32 FT-LB
CVT Check plug/washer 94109-20000 20 mm 32 FT-LB
CVT Drain bolt washer 90471-PX4-000 18 mm 32 FT-LB

 

+2

Even if there's a little bit of a lip pressed into it around the hole, it can be made flat again with a file. It's aluminum so it's very easy to do.

Unlike my Subaru crush washers which are kind of U-shaped in cross section and they do get deformed when the drain plug is tightened. I wouldn't try reusing one of those.