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Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 9:25 am
by daverubberduck
I am getting a nasty noise when the clutch is depressed, when the clutch is lifted all is quiet. I think this must be the release bearing, please correct me if I'm wrong. If I'm right then it is very annoying because Spyder replaced it in Nov 2016 and the car has not done many miles since then. I'm going to attempt to replace it myself but I've read on this forum that the bearings are now all manufactured in China. Does anybody know of a source of bearings in the UK that are not Chinese crap?
Dave

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 10:03 am
by rgh0
Yes sounds like the thrust bearing has failed. The original RHP bearings and same bearing that SKF used to make appear to be no longer available. The only commonly available bearings are a no name cheap copy which appear to have a very variable service life. I believe NSK used to also make the same bearing but I cant track that down either currently.

I think its time for someone to identify a currently available thrust bearing from a quality manufacturer that can be fitted with an adapter to the carrier or a new carrier made for it. It cant be that hard for someone with a little time :lol: ( what are you doing between making drive shaft kits and building a new engine after your holiday Col at Elan Trikbits )

I am down to my last NOS RHP bearing and time to see if my secret source has anymore left :roll:

cheers
Rohan

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 11:35 am
by alan.barker
For me it is more likely to be the Needle Roller Spigot bearing making noise when depressed
Alan

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 1:09 pm
by daverubberduck
Thank you for the replies. Please forgive my ignorance Rohan, but is the thrust bearing the same as the release bearing?

Thanks Alan, I guess I should replace both spigot bearing and release bearing once the engine is out, just to be sure.

The upside of this is that it forces me to learn to remove the engine. If these bearings are so unreliable then I can't keep paying others to do it.
Dave

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 1:15 pm
by rgh0
daverubberduck wrote:Thank you for the replies. Please forgive my ignorance Rohan, but is the thrust bearing the same as the release bearing?

Thanks Alan, I guess I should replace both spigot bearing and release bearing once the engine is out, just to be sure.

The upside of this is that it forces me to learn to remove the engine. If these bearings are so unreliable then I can't keep paying others to do it.
Dave



Yes release bearing is same as thrust bearing. It could be the pilot bearing also, I change both every time I pull an engine if they have been in for more than a couple of years. You can test which is failing by pushing the clutch pedal down and listening for noise before the clutch disengages. The release bearing will create noise as it loads up if its failed. The pilot bearing will only make noise once the clutch is fully release and you have a speed difference between the GB input shaft and the engine.

cheers
Rohan

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 2:40 pm
by daverubberduck
Thanks Rohan, that's great. I will do that test to see which it is.

One more question - to remove the engine is it absolutely necessary to disconnect the manifold from the rest of the pipe? I had a leak at the joins when I put it together recently, so used Holts Firegum and I think separating the exhaust could be very difficult. So I was wondering if I disconnect the manifold from the engine and also disconnect the silencer from the body, then I can tilt the whole assembly and leave enough room for me to raise the engine just enough to replace the relevant bearing. What do you think?
Dave

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 2:52 pm
by alan.barker
You can leave the manifold connected to the rest of the Exhaust System and tie to one side .
But you will need to remove the Exhaust Manifold Studs in the Head to make it easier.
if you have Screws holding the exhaust Manifold to the Head things are much easier.
Alan

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 3:13 pm
by daverubberduck
Thanks Alan. I've just been looking at it again and I was having doubts that the manifold could stay connected to the exhaust. If you say it can then that's a great relief. I will remove the manifold studs as you say.
Dave

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 3:28 pm
by Bigbaldybloke
I agree it sounds like the clutch release bearing, the only time I had a spigot needle roller bearing in the centre of the flywheel fail, it broke up and locked the gearbox input shaft solidly to the crank hence making the clutch in operational, i had to drive home with no clutch. I think this is unlikely to be the cause if you get the noise repeatedly each time you operate the clutch, much more likely to be the release bearing.
One thing not mentioned and hopefully it?s not this, is the crankshaft thrust washers failing and allowing excessive end movement on the crank, very unlikely, but possible.
On the exhaust, I have Allen head UNC screws instead of studs in the head to facilitate engine removal, quite a few comments on here about possible damage to the threads in the head, but I?ve never had a problem and it?s not something you undo regularly.

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 3:44 pm
by daverubberduck
I've just done Rohan's test and it is definitely the release bearing. My next problem is getting the studs out. I know the trick of using 2 nuts and tightening them together. I hope it works.

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 4:12 pm
by RichardS
daverubberduck wrote:I've just done Rohan's test and it is definitely the release bearing. My next problem is getting the studs out. I know the trick of using 2 nuts and tightening them together. I hope it works.



I use something similar to this, which makes insertion or removal of studs very easy. Just used it this afternoon for the inlet studs!

https://www.demon-tweeks.com/uk/draper- ... -dra58708/

Richard

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 4:38 pm
by daverubberduck
Hi Richard
I'm going to get one of those, they look brilliant. The link you gave was to a 6mm one. I presume that's the width of the stud. I measured the exhaust studs and they are more like 8mm, so I think that's the one I need.
Dave

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 7:16 pm
by RichardS
Hi Dave
Yes, think the 8mm is the correct size. (Can?t check now as my car is garaged away from home).
Much easier than the 2 nut method if the studs are tight.
Good luck!
Richard

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 8:16 pm
by prezoom
Be sure to let us know if the tool will fit on to all of the studs. There is limited room with the manifold in place on some of the studs.

While some use socket head cap screws, allens, I prefer 12 point bolts, which are easy to get here in the states. The bolt head is the same size as the thread size, i.e., a 5/16 bolt take a 12 point 5/16 socket. With quarter drive sockets, it makes it easy to access the bolts, and with a quarter drive short handled wrench, it is hard to exert enough torque to damage the cylinder head.

Re: Clutch Release Bearing

PostPosted: Tue Jul 17, 2018 9:31 pm
by Elanman99
daverubberduck wrote:Hi Richard
I'm going to get one of those, they look brilliant. The link you gave was to a 6mm one. I presume that's the width of the stud. I measured the exhaust studs and they are more like 8mm, so I think that's the one I need.
Dave


The extractor blurb says it for removing broken studs or bolts so how it would perform on a thread is open to question. I can imagine that if the stud was tight in the head casting it would mark the threads whilst it was gripping it. I really doubt that the extractor body diameter would be small enough to allow its use on at least some of the exhaust flanges anyway.

All in all the two nut method is favourite. Whilst the studs are out clean up their threads and the threads in the head so that all eight can be installed with fingers only. This very much eliminates the possibility of cross threading, which is something that could occur if the threads were tight and a spanner was needed.

Ian