Clutch parts for fitting a Triumph Overdrive gearbox onto a 1970 Triumph Herald 1200

[jagnut66]

48 minutes ago, DanMi said:

It is up to us to complain with threat of small claims if needed.

I have submitted a complaint but it will need others who buy these (or have bought them and then had to source the correct part) to do this as well, before anything will get done about it.

Best wishes,

Mike.

[johny]

Great let us know what response you get...

[jagnut66]

Well , as an update on this saga: Firstly, those who said the fat piece on the end of the push rod for the slave cylinder looked like an add on were right. 

I thought it screwed on and tried to unscrew it a bit to get more length in my (at the time) ongoing efforts to get the OD gearboxes gears to engage smoothly.

However, I found it was only tight with age and that, once I'd moved it once, the action of the clutch just pushed it back on again.

So I pulled it off and found a small piece of threaded bar hidden inside, acting as a spacer. In a light bulb moment I made my own longer version, thinking this would finally give me the clutch action I (or my replacement box at least) needed for smooth gearchanges. 

To no avail, try as I might, one, two and three got better but remained slightly 'notchy' when engaging. This I could have lived with but number four refused, point blank, to play ball. 

No matter what I did it refused to stop protesting whenever I tried to engage it. 

Unfortunately, I then realised what it was that it reminded me so much of. First gear on a Morris Minor gearbox. Why?

Because it has no synchromesh and, unless engaged from a complete standstill, will protest most vehemently whenever you try and engage it.

So my conclusion must be that I have been (whether knowingly or unknowingly I can't say) sold a pup.

I would say now that the synchromesh on fourth is shot and the others will probably come out in sympathy in due course. 

At some point I will have this box rebuilt, as I still think my Herald would benefit from an overdrive. However, for now, I must refit the original four speed box, to get the car mobile again.

Thanks again for all your advice along the way, it has all been very useful and I will consider this a practice run. 

Best wishes,

Mike.

As a post script, I note that with my four speed the slave never had an extension piece fitted, so I will leave that off unless it proves necessary.

Something else for the spares pile..........

 

 

[johny]

I wouldnt say a pup (well depending what the ad promised and how much you paid) as these are old secondhand units that quite often the seller has no way to test. Synchro failing on 4th is unusual as that one normally has an easier life because the hard acceleration is over by the time you change to it. However the other synchros could have been renewed previously or even, as is quite common, swopped around....

Unfortunately changing synchro rings means a complete strip of the gearbox internals (OD is left alone) but with the manual and a bit of patience is doable👍

[johny]

Thinking about it I wonder if the 4th gear synchro has got stuck. Its a ring that slides onto the cone part of the gear being selected and acts as a mini clutch before the main gears engage but can get stuck on the cone and not return when another gear is used. This may mean that next time you come to select 4th effectively there is no synchronisation and there will be a lot of graunching as youre experiencing.

The rings are just about accessible without a strip down by removing the gearbox top cover and then it might be possible to free it off in situ - sure a gearbox guru will be along soon to check if Im talking rubbish😁 

[Pete Lewis]

unless there is some silly geometry problem inside the clucth housing mechanism addind spaceres to the push rod only moves the slave piston somewhwere

elsis in its cylinder

all synchro relies on a clearing clutch   remember to synchronise the dog teeth  you have to whizz the clutch disc up or down to a mating speed  inthe blink of an eye

any drag will give a clash of teethas the ring grip cannot overcome the clutch drag

same applies to the accurate chamfered teeth on the ring the sleeve and the gear dog teeth  any chimbled teeth will cuase synchro to be weak or ineffective 

[johny]

Unusual to be that bad on 4th and ok on the other gears isnt it Pete? Could a stuck synchro be the cause?

[Pete Lewis]

certainly baulk rings can get pitched and stuck on the cone  and yes  top off and a light pry with a scredriver to free it if its stuck works fine 

if its  a loose rattley ring its not stuck  you can also see if the ring has worn and bottomed out .

but constant clashing over a period will clatter the dog tooth chamfer and then the rock over fails and the ring lets go halfway through a change 

in general the chamfer is a /\ around 55deg    not a /*\   where the chamfered  tip has been chimbled away on all three parts  gear,, ring, sleeve

pete

 

[DanMi]

One thing that I would check just in case is your crankshaft end float as problems here can feel like a clutch issue. Try to move the front engine pulley back and forward, there should be 4 to 8 thousands of an inch but in a worst case where the thrust washers have fallen out it can move 4mm or more which stops the clutch working properly

[Pete Lewis]

and other things that affect noise and such is a missing flywheel spigot bush  so the input shaft is supported at  both ends 

Pete

[jagnut66]

8 hours ago, johny said:

Unusual to be that bad on 4th and ok on the other gears isnt it Pete? Could a stuck synchro be the cause?

One thing I did forget to mention is that I always had a (not loud but distinctive) 'click click click click click click click etc etc'

whenever first was engaged (not present on two or three though).

First gear engaged though, apart from being notchy in doing so, like the rest.

Best wishes,

Mike.

[jagnut66]

Right, the four speed is back in, clutch bled and (with the reinstatement of that 'extension' piece) I can select all four gears and reverse. 

I'm having a little trouble getting rid of that last little bit of air in the system though, so, following some old advice on here, I'm leaving the clutch pedal weighted down overnight. 

I would use the easy bleed kit but I don't seem to have a suitable lid to fit my new master cylinder.

On that subject, one difference I have noticed between my original lid, the lid on my brake master and the lid on my new slave master, is that the new slave master doesn't have that small air hole in the centre of the plastic lid, unlike the other two. 

Would it be a good idea to drill one into it? It's a different size to the original lid, so I can't just swap them over.

Best wishes,

Mike.

[johny]

How do you know theres still some air in the system? Its easy with brakes but clutch is spongy by nature....

The cap will be vented so no need to drill a hole. Might be a 'dual layer' type but must allow air in somewhere or the reservoir would pull a vacuum in use😁

[jagnut66]

49 minutes ago, johny said:

How do you know theres still some air in the system?

Started off with clean engagement, just after bleeding through. Then became a bit more reluctant to let me put her in gear without resistance. Pump the pedal a couple of times and it's happy again.

Best wishes,

Mike. 

[DanMi]

Have you checked the crank end float? as that can make you need to pump the clutch to push the crank forward, then next press it works, happened to me many years ago spent ages trying to bleed the clutch, before I finally found the culprit (no internet help back then!)

[johny]

yes could be air or the master cylinder internal seal leaking. This is the one that shuts off the reservoir when you first press the pedal so that oil is pushed out to the slave. If it doesnt seal well oil seeps back to the reservoir and the clutch starts to engage again....

[Pete Lewis]

caps can have differing methods of breathing but they must breath some how .

this seems like you still have air trapped in the slave 

pete

 

[jagnut66]

21 hours ago, johny said:

yes could be air or the master cylinder internal seal leaking

I hope not, it's the second new one I've bought and fitted recently.

21 hours ago, DanMi said:

Have you checked the crank end float? as that can make you need to pump the clutch to push the crank forward, then next press it works, happened to me many years ago spent ages trying to bleed the clutch, before I finally found the culprit (no internet help back then!)

I'm not ignoring you Dan, just hoping it doesn't come to opening up the bottom of the engine to replace thrust washers. I need the car on the road at present.

21 hours ago, Pete Lewis said:

this seems like you still have air trapped in the slave 

I'm hoping so Pete, I've ordered a spare cap for the master, which I can adapt to use with the easy bleed kit. If the problem doesn't go away during use I will give it another bleed through using this, as the first option.......

Best wishes,

Mike.

 

[Pete Lewis]

forget the easy bleed  get a size 9 on the pedal and give it some beans 

Pete

[johny]

Another possibility is to remove the slave and carefully angle it downwards for a while so any air in it floats up to the bleed nipple which you can then crack open to vent without pressing the pedal before reinstalling....

Also Petes right about some rapid and enthusiastic pedal pressing when bleeding because you can imagine a small bubble of air in the bend of the pipe just before it connects to the MC. That bubble has to be continuously pushed down by fluid flow to the slave bleed nipple otherwise it just floats back up to sit in the high point again!

[Badwolf]

What was it that was posted here some weeks ago...'hard in slow out'..well I think that it was this forum!!

[johny]

I would add repeat quickly for the reason stated above but of course none of it applies if Mikes going to use a pressure bleed😄

[johny]

In fact with manual bleeding I think youre best off tightening the bleed nipple after a fast press and hold of the pedal so as to avoid any chance of pulling air back in round its thread. Then of course you can release the pedal however you like👍 

[NonMember]

2 hours ago, jagnut66 said:

I'm not ignoring you Dan, just hoping it doesn't come to opening up the bottom of the engine

You can assess the end-float without opening up the engine. If it proves to be excessive then you're wasting your time trying to fix the problem any other way, so you'll just have to live with a bad clutch until such time as you can replace the thrust washers. Besides, it's perfectly possible to replace the thrust washers in situ - you only need to drop the sump and the rearmost main bearing cap.

[daverclasper]

2 hours ago, NonMember said:

If it proves to be excessive then you're wasting your time trying to fix the problem any other way, so you'll just have to live with a bad clutch until such time as you can replace the thrust washers. 

So some excessive end float (without the thrust washers actually dropping out and then damage to block/crank), where the crank is moving more than spec, is not harming the engine in any way?. Genuinely interested.