[Healeys] Clutch renewal follow-up

Tue Apr 13 12:54:17 MDT 2021

Hi Paul,  I did my clutch a few years ago on my BT7, and I am just re-visiting now as I am re-building the engine.

Opinions will no doubt vary, but my suggestions are:

1.	I would ck the flywheel for any shallow grooves (I assume there are no deep ones) by running a fingernail across it, and also look for any discolouration that would indicate hot spots where a slipping clutch might have generated a lot of heat.  If either are present, I’d suggest re-facing the flywheel, but otherwise I’d leave it alone.  If not re-facing the flywheel, I would use a small flat metal block and some fine emery to take any glaze off the flywheel, just make sure you do it evenly all the way around and keep a band-aid handy for when you catch a knuckle on the locating dowels.
2.	Some may suggest balancing the flywheel and clutch together, but unless you have had vibration issues, I’d suggest it is not worth it if you are not balancing the rest of the engine.  If you have not taken the pressure plate off yet, I suggest marking it and the  flywheel with punch marks so if you re-use the pressure plate it can be put back in the same orientation as before.  If your engine has been balanced in the past, there should be marks already there.
3.	As it is an inexpensive item, I suggest replacing the pilot bush in the end of the flywheel.  Soak it in oil overnight before installing the new one, and put a light coating of grease on the inside of it before you re-attach the g’box.
4.	Brake cleaner should work fine for clean up of pressure plate and flywheel.
5.	My recent experience has been led me to think that the older Borg and Beck (B&B) clutches are better than the new ones. I also think that we discard pressure plates when they still have a lot of life in them.  I would look at it carefully and if the friction surface is in good condition and there is no noticeable damage to the rest of the pressure plate, I’d be inclined to re-use it.  When I did mine a few years ago I laboriously re-faced the friction surface by hand with a small, fine file.  It was a horrible job.  I understand there are places that will disassemble the clutch and properly re-surface it.  Because the friction surface is “recessed” inside the cover, this cannot be done without taking it apart.  In the intervening years I did acquire an NOS B&B clutch pressure plate which I am now fitting with the engine rebuild, but I am keeping that old one as I think it has much life in it yet.
6.	For the record, the problem I had 2 years ago was with the driven plate.  B&B changed  the way they cage the springs that absorb the rotational loads, resulting it being marginally deeper (thicker?) than the original.  So when is was all back together the clutch would dis-engage, but when the pedal was fully depressed the three arms that release the pressure plate fouled on the cages and produced an unlikeable noise (British understatement).  I did not get any satisfaction from B&B, despite heroic efforts of the dealer I was working with, so I took a full refund, cleaned up the old driven plate (which had lots of friction material left), and re-installed it with the old pressure plate (with the hand-filed surface), with an NOS throw bearing and it worked fine.
7.	Lastly, I would not be tempted by new designs such as the one offered by DW.  I have never had a problem with a Healey clutch (the recent re-design by B&B excepted), and the original clutch was made to work with the engine as a package resulting in a smooth running unit.  I would not upset that unless you are building a race engine and tackling all aspects of the engine.

Good luck with it,  Mirek

From: Healeys <healeys-bounces at autox.team.net> On Behalf Of Paul Leeks
Sent: April 13, 2021 12:49 PM
To: healeys at autox.team.net
Subject: [Healeys] Clutch renewal follow-up

Hi chaps

A couple more questions, if I may ...

I now have the gearbox off and the old clutch out.

Should I replace the whole cover assembly or, as it seems fine, can just I clean and reuse with the new clutch driven plate?

I may, as advised, get the flywheel resurfaced.  Either way, should I use brake cleaner to clean the flywheel and clutch assembly?

Many thanks

Paul Leeks

100/6 BN4

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