UN1 13 Grinding when trying to shift

[Ian Anderson]

Mike

How about sending Michael B your "spares"
Once he gets one to work he returns the other and pays for the one he keeps!

Saves putting it on evil bay!

Ian

 

[Mike Pass]

Unfortunately the ones I have left are for the small size pipe!
Cheers
Mike

 

[Michaelb]

That would have been good, but figured as much whenyou told that the 3/4 was the biggest you ended up with

I went and bought the 7/8 so now just waiting for it to arrive probably next week and ill see if it works if not i´m just gonna keep going til it does:thumbsup:, although have some other things i want to adress while im at it one thing i have a leak between the bellhousing and the gearbox so gonna pull the gearbox out and get it fixed...just for the hell of it, really don´t like drips so might be a little before i get it all together again.

Michael

 

[Michaelb]

Well got the gearbox off, found that the oilspill came from the bellhousingbolts to gearbox and not from the centershaft as i expected so need to use some rtv or the like on the bolts.

Another thing i found was that the release bearing sits on a sleeve and actually can´t move more than the 12 mm until it hits the end of the sleeve whis has a bead so the 3/4 cylinder would probably be able to push a little further but couldn´t do to the stop, anyone else encountered this and has a good solution? pretty sure it needs more throw to completly disengage.

by the way the clutch plate is a 10.4" AP borg&beck and the pressureplate i cant tell as have no brandname on it, the flywheel is an 14.1" 168 tooth centerforce to fit the 400 crank(my engine is a chevy 383 stroker, my appoligies to the ford people

Another thing i found was the pilotbearing had some indentations from being hit by the gearbox inputshaft about 1 mm in, this i assume is the reason the clutch dragged, when i pulled the clutch the pilot was loose and just dropped out:stunned:

Have a couple of pictures but not sure as how to post, would be nice if anyone had some ideas as to get it done right so i dont have to go through this again

michael

 

[Mike Pass]

I am a bit puzzled as to why the sleeve that the release bearing slides on has a bead on it. On my setup I did some careful measurements of the distance of the clutch fingers from the face of the bellhousing and also the rest position of the release bearing etc to ensure that you have sufficient space and movement of the release bearing to fully operate the clutch. Try and post some pics so we can see what the problem is and compare what you have to our setups.
To post pics on here you will need to change the size to large web size which is 640 x 480 pixels. There are several free utilities to do this. If you have Microsoft Office then there is a utility in there called Office Picture Manager which will do the conversion. Once you have the pic in the correct size then use the manage attachment utility to browse for the pic and then upload.
Cheers
Mike

 

[Michaelb]

Allright got it, first is of the releasebearing completly retracted, second all the way forward resting on the "lip" approx. 12 mm between the 2 and the third is of the pilot bearing where the inputshaft made its impression...

 

[Mike Pass]

The pics of your set up are a bit of a puzzle. The UN1 - 13 (Renault 21 Turbo) clutch mechanisms that I have seen do not look like your pictures. The usual set up is not the rod with two fingers shown in your pics.
They usually have a pressed steel arm which pivots on a ball inside the bellhousing. The slave cylinder pushes directly onto the end of the pressed steel clutch arm and the other end has a fork which attaches to the clutch release bearing holder. This bearing holder then slides on the tube surrounding the gearbox mainshaft.
I will try to find a pic of my set up to illustrate.
This may be the cause of your problems. Are you sure that your box is actually a UN1 13 from a Renault 21 Turbo or has it been modified with an aftermarket rod and finger arrangement?
Cheers
Mike

 

[Michaelb]

Yes it is a 21turbo (un1-13 on tag) reason why it looks different is because its mated to a chevy so has a custom made chevy-renault belhousing instead of the ford one. Other than that the principles are the same but on the chevy the 2 arms only pushes the bearing the 2 are not attached so the springs(arms) on the pressureplate will push the bearing back there is no returnspring, still dont know why the sleeve only allows 12 mm throw if more is needed, very strange

 

[Mike Pass]

I think your problems are related to the custom bellhousing setup you are using. The rod with two fingers to operate the clutch release is not giving you the neccessary amount of movement to clear the clutch fully. If the clutch doesn't fully release then the gears will grind and it will be a pig to change gear. Also if the step on the input shaft hits the spigot bearing in theend of the crank the two will tend to rotate together and have the same effect as clutch drag.
We normally use the Renault bell housing that comes with the box and have an adaptor plate between this bellhousing and the motor. This allows the use of the Renault clutch release lever, release bearing and slave cylinder etc.
If you retain the custom bellhousing that you have you will need to ensure that the gearbox shaft does not foul the spigot bearing in the end of the crank and devise a way to get more movement of the release bearing to ensure that the clutch releases properly. The best start point would be to measure exactly how much movement of the clutch release fingers is needed to release the clutch fully. Make up a rig with abig bolt and a metal bar and use a digital caliper to measure the amount of movement needed to free the driven plate. Once you know the amount then see if you can get that amount of movement using your setup. If you can't get this to work out then get the Renault bellhousing, clutch lever, bearing carrier etc. that was on your box or another one and a suitable adaptor plate for your motor. I have attached a pic of a UN1 which gives an idea of the normal arrangement.

Cheers
Mike

 

[Mike Pass]

The other alternative if you can not get enough movement out of the current rod and finger arrangement is to convert your bellhousing to a concentric slave cylinder.
Cheers
Mike

 

[Michaelb]

Dosn´t look like its a problem with the 2 fingers, they are able to move well beyond where the sleeve stops it, the sleeve has the shape of a trumpet and when the bearing gets to the end its not allowed to go any further (see pic 2) if the sleeve was straight it would be able to move further so i think i need to replace this to get it to work properly. I would think that the sleeve would be on all of the un1 gearboxes for the bearing to move on, regardless if its the original bellhousing from renault, it just woudn´t have the trumpetshape that makes it stop when coming to the end, is this incorrect? If i am to replace the sleeve do anyone know how its attached, i guess the bellhousing need to come off to get it out but if there is some way to alter the existing it would be preferred. With regards to the spigot bearing i now had it milled down 2 mm so that i will clear the inputshaft. This might have been the cause to all this, as you said it most probably is what caused the clutch drag.
As it is now really don´t want to assemble and find out i still need more throw so i will defenitly try your idea with regards to how much movement is needed.....good thinking and this should clear up what my next step should be.

Alternative as you said Mike is to go the concentric way but dont think i can get enough clearance to do this.

cheers
Michael

 

[Phil]

Michael:
Just looking at your photos of the setup it sure looks like the splines on your input shaft were hitting the pilot bearing. I think you may have located most of your problem, and I can see the interference between the two were causing the drag.
I hope you have solved the problem, but I am curious if you had a solid feeling at the bottom of the clutch pedal travel where you are contacting that bead you talked about.
Good luck, and lets hope you are over the hump on that problem.

Cheers
Phil

 

[Mike Pass]

Maybe the trumpet end has been put on to prevent the release bearing from falling off the end of the tube. If you change the trumpet part by heating and hammering or by grinding it away then the bearing may go too far in operating the clutch to fully free and fall off the tube. The standard tube does not appear to have this trumpet section so a swap may also be possible. A clip to retain the bearing onto the two clutch actuating arms should be fairly easy to do. As you don't have much space in your bellhousing knowing the distance of the various movements exactly should help you to get it all working OK.
Cheers
Mike

 

[Michaelb]

@Phil,

Absolutely right about the bearing, not quite sure that its only that, do feel that i need a bit more throw to really be sure it will disengage so im going to measure how much it will take to release it per MikeP´s instructions, also in the future as the clutchplate gets worn, i think i´m just on the edge as is now.

I did have a solid feeling when pedal was pushed it did seem like it had a stop built in to it and when trying to bleed the slave i could hear a small "clonk" when it was pressed all the way so that was when the bearing was at the end of the sleeve, just didn´t know it, i have no doubt that if the sleeve is altered or removed it would be able to move a bit further with the existing mastercylinder, now i allready ordered the larger master so will go with that just to be on the safe side.

@Mike
I think you are right its made that way to prevent it sliding off so i could either get the sleeve replaced with a standard one and as you say wire it to the arms og i could do another trumpet the correct lenght once i determin how much throw i will need to completly disengage the clutch, the idea with the stop is actually pretty smart as it can be made to precisly disengage, once it hits youll be able to adjust your pedal to suit so that only the exact pressure and movement is needed, also would eleminate the need for a pedal stop, so if you think about it quite brilliant really...its just strange that only a 12mm throw was allowed:furious:?.

Cheers
Michael

 

[Mike Pass]

The problem with a stop is that as the clutch plate wears the clutch fingers move outwards. If you have a set up like mine which is fairly marginal on movement to clear the clutch then as the driven plate wears it will go out of range. An adjustable slave cylinder rod allows the rod to be shortened as the clutch wears or use a range of rods with slight length variations as I do. However the movement at the release bearing will still alter with wear. It may be useful to measure the position of the clutch fingers with a new driven plate and also a worn one (or simulate with a packer) whilst you are doing your measuring so you will know the range of positions before you start working out the arrangement for release mechanism.
Cheers
Mike

 

[Michaelb]

Good points, will try and get the rig made this weekend to deteermin throw, ordered new sleeve and gaskets etc today at renault and will go with that ill adjust the throw on the slave accordingly, hopefully ill have all the parts next week so that i can get driving again

One thing does anyone happen to know where to get a new driven plate 265 mm (10.4") AP Borg and Beck 21 splines for the un1 even have a partnbr on it 47809/47810 bu nothing comes up other than some rover applications with 10 splines, tried mailing Borg&Beck but no response..Other brands with same spec could do as well.

Michael

 

[Keith]

Hi Michael from Danmark. The title of this thread intrigued me so I have read it right through and am somewhat puzzled. Sorry to dilute your thread a little but when I saw the words "Grinding Whilst Shifting" I thought you meant this:

Sorry mate...

 

[Michaelb]

.....Should have known just by looking at your avatar name :laugh::laugh::laugh:good one mate:thumbsup:

Cheers
Michael

 

[Mike Pass]

I use an AP 21 spline driven plate on my car. I am sorry but I can't remember the diameter. Contact Mick Sollis at Southern GT which is where I got mine. He should be able to tell the diameter of the AP 21 spline driven plates that he has.

Southern GT - Manufacturer of the new Southern GT40 Replica-8d39gcg18ggu92otans98cq2h2

UK Tel:01489789143

Cheers
Mike

 

[Michaelb]

Allright got the driven plate fixed AP has one 265mm, AP borg And Beck no longer operate under that name. Techcraft supplies the AP one.

Well got the setup tested and looks like i need 1 mm more throw than what i can currently get when my current sleeve is on, so need a new sleeve...To get that i went to renault and he found the partnumbers for the gaskets, oring and the sleeve, but it looks much different on the picture than whats on yours mike, it has a trumpet like end but different from mine aswell. What i will need is a straight sleeve which will give me more than the 12 mm throw of the release bearing, anyone know where to get this? can´t find any pictures other than what i have been given by renault. Any and all help appreciated. thanks

Michael