front wheel bearings

[IslipMinor]

(0.375" is probably OK, but it would stick out 1/16")

No, 3/8" thick is not OK!

The oil seal is inserted with the open end towards the bearings, and most of the stiffness is in the closed end, which would be out in fresh air. The seal will appear to be fine, but without the closed end being within the hub, the seal can very easily work its way out, and allow the grease to escape.

From a non-Minor application I have seen this happen, with a very similar over-width oil seal.

[dudload]

I can remove that bit from the cut and paste - assumed most people would just go for the size that Phil said would fit and only get the larger in an emergency (whatever that could be!). better safe than sorry i suppose

[philthehill]

These are the details from a used Minor front hub seal that I have just extracted from a Minor front hub.

Make.........................,....GACO

Outside diameter.............54mm

Inside diameter (used)....34.8mm

Thickness/depth of seal.............7.8mm

Markings on seal.............M1 137212 5/16

Can you please put in the link to the size quoted in the post above.

Phil

[IslipMinor]

Phil,

Unlike the front wheel bearings, which are nominal 'metric' dimensions, the oil seal is nominal 'imperial' dimensions, so the sizes are 1.375" (1 3/8") ID, 2.125" (2 1/8") OD and 0.3125" (5/16") wide/thick. The Gaco reference 'M1 137212 5/16' quoted uses these dimensions - '137' = 1.375", '212' = 2.125" and 5/16 = 0.3125".

The bearing/oil seal suppliers these days do sometimes use metric equivalents of the imperial, sizes, so some care needs to be taken when ordering.

[dudload]

well i have egg on my face - the link to the quote is below, but it turns out the original comment was actually from.... IslipMinor!

https://www.mmoc.org.uk/Messageboard/vi ... hp?t=21707

a right mess i've created!

[philthehill]

Richard
Many thanks for the explanation and cross referenced sizes.
It was easier to grab hold of a metric clock vernier than get the batteries out and fit them to the digital vernier (I never leave batteries in any measuring equipment in case of leakage).
Though any good bearing/seal supplier should be able to cross reference the GAGO seal part number and come up with the imperial size hub seal.

dudload
Thanks for the link - I could not remember posting the size of a Minor front hub seal only seals fitted to Marina hubs when converting the Minor drum brakes to Marina disc brakes.
It happens to all of use so you are not alone.

Phil

[IslipMinor]

Mmm! Interesting, and thanks to 'Dudload' for finding it. My comment about 'probably OK' to use an over-width seal was made in 2008 - my experience with a non-Minor seal working its way out in a similar situation was in 2016. Hopefully not too many people used the 2008 'probably OK' suggestion!

I have taken the opportunity to add a note to the original 2008 posting to clarify the need to use the correct seal width.

Note to Moderators - shows the benefit of being able to edit/correct a legacy posting on the MMOC Messageboard, unlike some BBS where once posted, it is locked for eternity.

[BLOWNMM]

For what it's worth I am using tapered roller bearings on my MM with 1000 swivel pins. Bearing no's 30205 and 30303. Because of the increased width of these bearings I am using a SKF 13662 seal - 1.375" X 2.129" (for a bore of 2.125") X 0.25 wide. They do not protrude beyond the hub.
Bob
https://kscdirect.com/item/CR%2B13662/C ... RE%2BSEALS

[dudload]

well the saga continues - i've received the bearings (which look to have been manufactured in 1991 and 1988) but have received one 7205BEP and one 7205BECBP. i take it it's not safe to use different bearings on different sides or is the BECBP just a better version of the BEP and safe to use?

[IslipMinor]

Looking up the differences in the SKF catalogue shows that both are 40° angular contact bearings (the 'B' after the bearing series and size indicates this), but the 7205'BEP' is the 'basic design bearing', whereas the 7205'BECBP' is one of the 'universally matchable bearings'.

From previous posts the 7205BECBP is the 'face adjusted' version that is the correct specification for the Minor front hub. It also has slightly higher load and speed ratings than the BEP version. With all the problems that have been reported on here over the years, I would suggest sticking with the 7205BECBP version, and returning the basic BEP to be exchanged for the correct BECBP bearing.

The outer bearings should be 7303BECBP, which is the same 'face adjusted' version - are they? Both the 7303 versions have the same load and speed ratings.

[Kevin-G]

Do I need single lip or double lip seals?

[philthehill]

Single lip seals

[Kevin-G]

Will it matter if I use the double lip seals as that's what I have ordered?

[philthehill]

Provided that that both lips of the seal sit on the oil seal rubbing seat there should be no problem.
Can you please provide details (or a link to) the double lip seal to be used.

[Kevin-G]

They are from Bearing-King.co.uk. Seemed to have good prices on the bearings recommended here, although I did go with the cheaper BEP bearings. Looking at the data sheets for both couldn't really see how the Minor would require the higher spec bearings.

Search for 212137031 on their web site and it lists both styles of oil seal.

[philthehill]

Twin lip seal:-

https://www.bearing-king.co.uk/bearing/ ... 1-r23/9745

The bearings:-

https://www.bearing-king.co.uk/products ... ch=7205BEP

Whilst the BEP bearings are cheaper - cheaper is not always the better solution.

[dubman1959]

Taper roller conversion, Beautiful.

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