43 replies to this topic

[imack]

A straight cut box (assuming it's syncro engagement and not dog engagement) will select gears exactly the same as a standard helical box.

[Chris1992]

Right. Update.

 

Just given the car its first shakedown with the new engine, and regarding gear changes, it seems to behave itself! I can go up and down through the gears with no issues at all while moving, but it still remains a bit tricky when stationary. 

 

A bigger concern that has made itself known is the clutch slipping when putting my foot down or pulling away. This is a brand new engine with a brand new clutch plate, so I'm hoping this is just a case of being very careful with it until it's bedded in properly.  

[nicklouse]

 Never needed to bed a clutch in.

which flywheel assy? Which friction plate? Assembled by? 

[weef]

I notice from your previous messages you have set the arm clearance to 0.2mm, that is only 0.008", the setting required is 0.020". This will have to be reset before you go any farther. In saying that there still should be a little clearance and no pressure should be on the clutch to make it slip as you say.It may possibly be the case you would be better off stripping out the clutch assy to check all is OK as it appears from what you say something is wrong in this area.

[Chris1992]

Never needed to bed a clutch in.

which flywheel assy? Which friction plate? Assembled by?

  

Flywheel is a Minispare lightened flywheel. I couldn't tell you where the friction plate was from, as it was supplied by specialist components. Everything was assembled by them too. I plan to call them tomorrow to hear their suggestions.

I notice from your previous messages you have set the arm clearance to 0.2mm, that is only 0.008", the setting required is 0.020". This will have to be reset before you go any farther. In saying that there still should be a little clearance and no pressure should be on the clutch to make it slip as you say.It may possibly be the case you would be better off stripping out the clutch assy to check all is OK as it appears from what you say something is wrong in this area.

Ah right ok thanks for the heads up! Balls up on my part. I'll get that reset asap and see if that helps, if not then yes I'll prepare myself for the long job of getting the clutch appart.

[Spider]

 

Are you having this problem when actually driving the car or just sitting in the workshop ?

 

I haven't driven the car yet, this is only from idling it in the garage. I am going to take it for its first test drive up the road this afternoon though so it will be interesting to see if that makes a difference.

 

Ah, OK, hold the horses here.

Go for a drive, get the oil warmed up and then look for issues - if there are any. Until then, I feel this 'issue' isn't something to consider what so ever.
 

[GraemeC]

I’ve heard of flywheel assemblies that have come out of SC needing setting up properly with regards to getting the spring flat

[Chris1992]

I’ve heard of flywheel assemblies that have come out of SC needing setting up properly with regards to getting the spring flat

 

Ah right that's not the best news. I'm fairly confident I can get the flywheel assembly out without removing the engine, so is this something I can do myself? 

 

 

 

Ah, OK, hold the horses here.

Go for a drive, get the oil warmed up and then look for issues - if there are any. Until then, I feel this 'issue' isn't something to consider what so ever.
 

 

Take a look a few posts up mate, but yeah you're right, after driving it I am in fact able to get all 4 gears. It's just clutch slip that's on the menu now! 

[nicklouse]

Ah right that's not the best news. I'm fairly confident I can get the flywheel assembly out without removing the engine, so is this something I can do myself?

If you have a big hydraulic press then you can.

 

but I guess you don’t. 
 

I would drop AC a message 

 

here is a how to video from some years back. So you can judge what needs doing.

 

https://youtu.be/iw4pFGfwZPM

[imack]

HRE is doing a very good series of YouTube videos and has done a couple of very interesting ones regarding flywheel setup.

https://youtu.be/C3c5EcpYiP8

https://youtu.be/4lEbKGpZ4xw

[Cooperman]

I did once have a similar problem when I fitted a Borg & Beck competition diaphragm onto a 970 Coper 'S'. It was impossible to set the clutch to operate correctly.

In the end, I striped it out and discovered the clutch outer casing (which holds the diaphragm) was distorted by about 0.040". A new standard unit cured the problem. That was a long time ago and obviously a very rare issue.

Good luck with getting this one sorted out.

The clutch slip does seem very odd for a newly built unit with new parts. It tends to indicate either oil on the clutch plate face(s) or a diaphragm which is not fully loading the centre plate with correct pressure. Please let us know what you find.

[Chris1992]

I did once have a similar problem when I fitted a Borg & Beck competition diaphragm onto a 970 Coper 'S'. It was impossible to set the clutch to operate correctly.

In the end, I striped it out and discovered the clutch outer casing (which holds the diaphragm) was distorted by about 0.040". A new standard unit cured the problem. That was a long time ago and obviously a very rare issue.

Good luck with getting this one sorted out.

The clutch slip does seem very odd for a newly built unit with new parts. It tends to indicate either oil on the clutch plate face(s) or a diaphragm which is not fully loading the centre plate with correct pressure. Please let us know what you find.

 

Yes indeed, very strange. I'll keep you posted on how I get on. 

 

HRE is doing a very good series of YouTube videos and has done a couple of very interesting ones regarding flywheel setup.

https://youtu.be/C3c5EcpYiP8

https://youtu.be/4lEbKGpZ4xw

 

 

If you have a big hydraulic press then you can.

 

 

but I guess you don’t. 
 

I would drop AC a message 

 

here is a how to video from some years back. So you can judge what needs doing.

 

https://youtu.be/iw4pFGfwZPM

 

 

Brilliant videos. Very informative, thanks guys! I've spoken with AC dodd on Facebook and he seems happy to help. I will be consulting with SC on this issue and seeing how they want to handle it first, but it's good to have options. 

[Chris1992]

Update. So this afternoon I went out to have a play with the stop bolt on the clutch wok. I corrected the clearance to 0.020", but while doing this I noticed that the return spring wasn't doing a brilliant job of pulling the arm back to the stop. If I pulled the arm away from the stop with my hand, it would return but do so rather slowly. I replaced the spring with a stronger one and this seems to have made a difference. However I am very suspicious of this solution as the spring required to do the job is incredibly strong and takes both hands to stretch into place. This surely can't be right? Does this highlight an underlying issue?

 

Something else I've noticed is that it is impossible to pull away smoothly. No matter how much rpm I give it, it will still bog down and judder. (obviously I am still being very gentle as I haven't run the engine in yet).      

[imack]

Is the release bearing plunger free to move in the wok?
The return springs are quite heavy but it should only take a very light spring to pull the arm back so that the release bearing is clear of the clutch diaphragm.

[Chris1992]

Is the release bearing plunger free to move in the wok?
The return springs are quite heavy but it should only take a very light spring to pull the arm back so that the release bearing is clear of the clutch diaphragm.

 

Yeah if I pull out the top clevis pin so that the arm is free from the slave then it moves back and forth very freely.

 

I'd also heard that a very light spring was all that's required, which is what worries me. I'm more worried about the juddering now to be honest.