365 Gearbox Diff Bearings

[Dilkris]

Sure JBC - I agree entirely with your comments - BUT - my adapted C spanner arrangement cost me nothing. I equally agree it would not work in a differing application where the collar may be tight - but on the 365 application they are not. (Well - shouldn't be)   
BDA - it is a generic tool - I have a set of them consisting of 3 different sizes - this one I use for setting rear shocks on my Harley. (Yes!! some of us over the water ride Harley's and at times I just wish Europa's were built the same....  )   

[jbcollier]

No worries, just want you to be aware of any potential pitfalls.  I snapped to tangs on mine using an adjustable pin tool.  I then got the tool from RD.

[Dilkris]

I have finally got to the bottom of the 365 differential bearing quandary; you will note in my first post on this thread that I questioned the bearing types as I thought they were would be the same, but I read 30207A FRANCE SNR on the non pinion side and 30207VO SNR B13 on the pinion side with a lotus specialist supplier here in the UK quoting one of the bearings as being almost 3 times the price of the other. (I wanted to know why  )
JBC very kindly supplied this link http://www.mecaparts.com/Cinematique/page.php?lang=0&sortie=html&col=A110&page=16, but interestingly the bearings here are shown as being the same; it was also suggested that one bearing has a higher load bearing rating than the other, hence the price difference.
The parts book, (accessed from this forum), shows the bearings with 2 differing part numbers, so 2 very different bearings.
I have now removed both bearings (which was interesting... and I can now confirm that the bearings are, believe it or not, very different.
The pinion side bearing has a 37mm bore and runs 16 rollers in the cage, whereas the non pinion side bearing has a 35mm bore and runs 17 rollers, (Higher load rating). The cup, or outer rings, that fit in the gearbox casings, are the same OD on both bearings.
The expensive bearing is the one with 17 rollers on the non pinion side which personally surprises me - it doesn't surprise me regarding the cost per say, but it does surprise me that this higher load bearing unit is fitted on the non pinion side  - (I would have thought it would be the other way round)
So - when you come to change your diff bearings on a 365 you cannot cut corners and buy 2 of the cheaper units, (like I was actually going to do) - you need one of each - and, as a plus point, you can't fit them on the wrong sides of the diff as they each only fit one place....!!!
Sorry for maybe rambling - but I thought it all quite interesting - or maybe I just need help               
   

[BDA]

That is interesting! I looked at the parts manual and found a similar situation for the 336 and 352. Both of those trannies also have different bearings on either side of the crown gear.

[jbcollier]

Hmm, dunno how I missed that.  Sorry!

Yup, two different bearings for the diff.

Have a closer look at the Meca list and there is an MP1638 for the larger size.

Been a while since I ordered the parts and overhauled mine.  Duh!

[BDA]

Hmm, dunno how I missed that.  Sorry!

Yup, two different bearings for the diff.

Have a closer look at the Meca list and there is an MP1638 for the larger size.

Been a while since I ordered the parts and overhauled mine.  Duh!

Just to be clear, I wasn't dinging you, JB. I was expressing my surprise that there were two different bearings. Without going back to my old yellow engineering books to see what axial loads might be generated by the ring and pinion gears, I wouldn't have thought that there would be enough to require different bearings (I do have an expansive capability to be wrong) but clearly there is something that drives that requirement. I wonder if this is common on transaxles and differentials.

[jbcollier]

Most diffs I have worked on have identical bearings hit the diff carrier.

[Dilkris]

Thought I would update on the 365 gearbox diff bearings saga – from my original thread you will recall I was looking for a bearing marked 30207A FRANCE SNR on the non-pinion side and 30207VQ SNR  B13 on the pinion side.

My local bearing supplier claimed both bearings were the same, (well - they have the same 5 digit number right?  ) – however closer inspection revealed they are very different and I later posted that the pinion side bearing has a 37mm bore and runs 16 rollers in the cage, whereas the non pinion side bearing has a 35mm bore and runs 17 rollers, (Higher load rating??). The cup, or outer rings, that fit in the gearbox casings, are the same OD on both bearings at 72mm.

The 30207A FRANCE SNR bearing, 35mm bore, (non-pinion side) is widely available and an equivalent is produced by many of the reputable bearing manufactures other than SNR. (See NTN photo)

The challenge became the pinion side bearing, (refer above.) Contacting many bearing suppliers in the UK simply drew a blank on this bearing.

Now SNR, (A French bearing manufacturer were bought out by NTN, (A Japanese Manufacturer) and now function in France under the name of NTN-SNR. I finally found a specialist who contacted NTN-SNR in France and “yes” although uncommon, they had the bearing in stock. 6 days later it was in the UK and with me. (see photo)

Happy days – highlighting what I have always considered to be utter witch craft when it comes to auto motive bearings.

Posted this update just for general interest – in the UK – I could only find one Lotus specialist supplying both these bearings - at some cost.

I still however would like to know why the diff was not manufactured to accept a common 35mm bearing – as opposed to the 35mm/37mm arrangement – it somehow reminds me of the 30/31mm bearing arrangement on the rear hubs of the S1/S2 before the twin cam standardized them at 30mm.

Unless of course I have missed something.. If I have it will come to light I'm sure when I come to fit them and set up preload and pinion/crown wheel back lash.... 

PS: "Merry Christmas" everyone   

[BDA]

That is great news!    Merry Christmas back at you!

[Grumblebuns]

Much appreciate the detective work you've done digging up the info for the 365 differential bearings.

Joji Tokumoto

[Blitzen]

Thought I would update on the 365 gearbox diff bearings saga – from my original thread you will recall I was looking for a bearing marked 30207A FRANCE SNR on the non-pinion side and 30207VQ SNR  B13 on the pinion side.

My local bearing supplier claimed both bearings were the same, (well - they have the same 5 digit number right?  ) – however closer inspection revealed they are very different and I later posted that the pinion side bearing has a 37mm bore and runs 16 rollers in the cage, whereas the non pinion side bearing has a 35mm bore and runs 17 rollers, (Higher load rating??). The cup, or outer rings, that fit in the gearbox casings, are the same OD on both bearings at 72mm.

The 30207A FRANCE SNR bearing, 35mm bore, (non-pinion side) is widely available and an equivalent is produced by many of the reputable bearing manufactures other than SNR. (See NTN photo)

The challenge became the pinion side bearing, (refer above.) Contacting many bearing suppliers in the UK simply drew a blank on this bearing.

Now SNR, (A French bearing manufacturer were bought out by NTN, (A Japanese Manufacturer) and now function in France under the name of NTN-SNR. I finally found a specialist who contacted NTN-SNR in France and “yes” although uncommon, they had the bearing in stock. 6 days later it was in the UK and with me. (see photo)

Happy days – highlighting what I have always considered to be utter witch craft when it comes to auto motive bearings.

Posted this update just for general interest – in the UK – I could only find one Lotus specialist supplying both these bearings - at some cost.

I still however would like to know why the diff was not manufactured to accept a common 35mm bearing – as opposed to the 35mm/37mm arrangement – it somehow reminds me of the 30/31mm bearing arrangement on the rear hubs of the S1/S2 before the twin cam standardized them at 30mm.

Unless of course I have missed something.. If I have it will come to light I'm sure when I come to fit them and set up preload and pinion/crown wheel back lash.... 

PS: "Merry Christmas" everyone 

Would you mind providing the name of your bearing supplier?
I did a "while you're in there" thing and removed my old bearing before checking availability of bearings and it seems the 37mm differential bearing is impossible to find.

[jbcollier]

I got mine from Meca Parts.  37mm ID bearing is MP1638.  35mm ID bearing is MP1630.

[Dilkris]

Blitzen - which side of the pond are you on? In fact - where are you? 

[Blitzen]

Blitzen - which side of the pond are you on? In fact - where are you? 

I'm in Calgary, Alberta.  Guess I need to update my profile.

I got mine from Meca Parts.  37mm ID bearing is MP1638.  35mm ID bearing is MP1630.

Thanks John, I'll try them

[Blitzen]

I got mine from Meca Parts.  37mm ID bearing is MP1638.  35mm ID bearing is MP1630.

How the heck do you navigate the mecaparts.com website?  Couldn't find the bearings or how to order them, ended up ordering generic ones from 123Bearing.com. Hope they are decent quality.