The Triumph Dolomite Club - Discussion Forum

Can anyone tell me the dimensions of the rear crankshaft oil seal on a sprint. I'm looking to buy a new seal and would like to know the exact size, I haven't started to take the old one out yet. Thanks adder.

These seals are readily available from the usual suspects, Robsport, Rimmers etc. or do you want to try to source one from somewhere else?

Part No. 143148

I wanted a payen seal but can't find one, so I was recommended to use a double lip seal, that is why I need the size of the seal. I have an idea what the size is but want to make sure before I send for it.

I see.

The end of the crank is 76mm.

The seal has an OD of 95.5mm. and an ID of approx. 72mm. the width is 9.5mm..

Thanks a lot for your help, I can order one now.

Has anyone identified the part number and supplier for a suitable double lip seal as that does seem to be a good idea.

The knowledgeable people I asked about the seal only gave me the part number in the sprint catalogue. No one gave me one for double lip seal or a supplier.!!!!!!!!!

Can you please provide the part number for the double seal.

I was told the sprint seal is the same as the stag, and to fit the double lip seal from simply bearings. The size of seal from Mad Mart doesn't seem to match up to the size of the double lip one. Can anyone explain, or is i/d size flexible, I would have thought not.

Adder57 wrote: ↑Sat Aug 24, 2024 3:55 pm I was told the sprint seal is the same as the stag, and to fit the double lip seal from simply bearings. The size of seal from Mad Mart doesn't seem to match up to the size of the double lip one. Can anyone explain, or is i/d size flexible, I would have thought not.

I/D has a bit of leeway built in, since it's supposed to put pressure on the crank to maintain a good seal. so the seal I/D is ALWAYS gonnna be smaller than the crank diameter, how much smaller is a matter for the engineers to work out. But it is a common thing to shorten the spring ring on a stock seal to make the lip seal better and last longer. It's possible that a double lip seal, which works inherently better, might have a slightly bigger I/D than a single lip one. But I doubt it'd be more than a mm or 2 at the most and if the I/D of the one you've been offered is more than the 76mm crank diameter, it's NOT correct!

HTH, Steve

This is all very confusing, has anyone actually measured the 143148 seal . If the crank size is definitely 76mm , why are people using 76.2mm . I also saw a seal advertised at E.J.Ward engineers with the part number 143148 with the seal sizes 9.52 x 95.25 x 76.2 ( .375 x 3.750 x 3 ). Has anyone else used this size seal.

Adder57 wrote: ↑Sat Aug 24, 2024 5:21 pm This is all very confusing, has anyone actually measured the 143148 seal ...

Erm! yes. I actually have a brand new one from Rimmers sat in front of me.

So why are people using a seat 0.2mm bigger than the crankshaft.