Jump to content

Recommended Posts

Evening all. The clutch on my consistently unreliable 1300 FWD has broken and I haven't got a clue why. 

I was driving along merrily, returning from a job 70 miles away. Approaching a roundabout it was suddenly reluctant to change gear, so I wrestled with it a bit. Some clattery noises ensued and I rolled off into a hotel car park. Engine running, gear would engage but car wouldn't move and something sounded distinctly broken.

Towed home, took the blighter apart and this is what I saw.

FWD-clutch-7432.thumb.jpg.861a9003f173005de0e32df721e2f500.jpg

FWD-clutch-7436.thumb.jpg.96a14cd8e4e7ff5b9ae7726d80eb57b7.jpg

The particularly troubling detail is that this is the 2nd time this has happened. 18 months ago a NOS Quinton Hazell plate suffered pretty much exactly the same fate. Here is what that one looked like:2019FWD_clutch-5219.jpg.85d94e83f04209dcfe7edede224c70f1.jpg2019FWD_clutch-5220.jpg.35d8aec780d195b04e3f000f3e8affcd.jpg

 

In both cases the clutch lasted about 1000 miles after being fitted. The latest one was a Borg & Beck, NOS again (I don't think there are any alternatives to old stock for these).

Now the other detail to note is that I've changed engines halfway through the life of the latest dead clutch. So it's on a different flywheel but the same clutch cover.

Any ideas what I'm doing wrong? Apart from owning this car in the first place... 

Link to post
Share on other sites

Ouch..... :confused:

In the top pic, with the cover plate hanging off the flywheel, is that as found or have you started removing bolts?

If that is as found, could be the root cause is bolts backing out on one side, possibly because the flywheel threads are damaged.

If that’s an in progress pic and the cover was found tightly bolted in place, damage like that is either due to run-out in the flywheel/clutch assembly or misalignment between the axis of the engine and the axis of the first motion shaft. 1000 miles between failures implies significant misalignment.

In the latter case you also need to consider whether something can move and become misaligned under load. Not least because that much misalignment would likely affect the normal operation of the clutch.

Link to post
Share on other sites

Thanks Nick, should have labelled top pic - that was after slackening clutch cover bolts.

Misalignment sounds like it's probably the explanation. On the FWD facebook group it's been suggested that the wrong sump gasket might be a cause. On these engines the sump is part of the gearbox casing, so alignment is affected by gasket thickness. 

Does that sound plausible?

I know I bought two proper FWD gaskets when doing the first engine rebuild, and I know I tore one of them lowering the engine into position. It's possible I tore them both and chucked a Spitfire gasket on instead (they're the right shape).

Link to post
Share on other sites

Having hauled out my factory manual for the fwd (the only part of it I have left) I’m left a bit bemused.

The usual causes of misalignment on the RWD cars are a bent backplate giving angular misalignment (producing failures much like your pic) or simple out-of-line caused by missing dowels and gravity.

The FWD arrangement is much more constrained and it’s not obvious how you can get angular misalignment (assuming the engine and gearbox faces are positively located). The gasket thickness could give simple out-of-line, but only small amounts. Enough? I don’t know, but I doubt it...

What’s left? I’d be checking the flywheel for run-out and having a really close look at the bearings that support the first-motion shaft. Getting more desperate, maybe check crank end float and how freely the clutch plate slides on the splines. Do you use grease on the splines?

Was the clutch operation “normal” up to the point of failure? Does it have any “normal peculiarities”? (As it were:tongue:)

Link to post
Share on other sites
Posted (edited)

Thanks for your time Nick, it is much appreciated! 

My first rebuild of this engine (pre clutch explosions) did include removing the input-shaft bearing and gear, to replace with uprated items from Canleys (see pic below). Might have to revisit the gearbox, although it all seemed square on reassembly. I think there are some shims involved with the bearing but can't see many options for angular misalignment unless I distorted the casing. Which is possible. 

I can check the flywheel with a dial gauge and see what that's like, but it certainly looked true when spinning (you can watch flywheel with clutch cover off). Crank end-float has been well within tolerance for both engines, as I did the bottom ends both times and replaced thrust bearings.

Yes I put a little molybdenum grease on the splines. I think I first did that because there was some graunching on operation. That may have turned out to be the release bearing, which I've replaced a couple of times. 

It has been a little stiff getting into gear, and I had been wondering whether my new clutch master cyl was the wrong bore and not giving quite enough travel. But I also need to weld up and re-drill the clutch pedal clevis pin hole, as there's a lot of lost motion there.

Additionally, a little bit of judder had started to occur on take-off shortly before the breakdown. I assumed this was contamination but maybe something more sinister!

 

triumph-1300-powertrain005_comp.jpg

Edited by PeteStupps
Typo
Link to post
Share on other sites

I lost a clutch like that my 13/60 (twice) it was a bent back plate that caused the problem as Nick suggested.

On the FWD is the gearbox bolted to the bottom of the engine? if it wasn't sitting flush, or too low or high it could cause the shaft to be misaligned. Or is the input shaft bent or running out of true, that could bend the centre plate and break it. Is the bearing at the end of the crankshaft ok?
On my Herald the bearing in the end of the crankshaft was missing, when I replaced it I started to have the problems with the clutch plate breaking....  

mike

 

Link to post
Share on other sites

Nothing jumps out.  Not surprised that there was the occasional odd noise and some difficultly getting into gear towards the time of demise.  Could be several reasons for that!

It is perhaps odd that the damage extends to the actual friction surfaces.  The ones I've seen fail from misalignment have tended to be cleaner with the friction surfaces intact and the damage restricted to the blades joining hub and outer ring being snapped.  Does that match your experience Mike?

Also, for that much destruction in 1000 miles I'd anticipate a fairly large misalignment to be needed.  Enough to potentially cause sticking on the splines with the attendant drag issues from the outset.  As a comparison I'm fairly sure the Vitesse had an offset of between 0.5 and 1mm in the years of my W58 conversion.  That ate the spigot bearing a bit and the contact patch on the diaphragm fingers was rather large and shiny, but it worked like that for over 20k and I actually took it apart because friction plate was intended for a 1.6 van of about 60bhp and the cushioning springs in it didn't like the 2L torque and collapsed.

Link to post
Share on other sites
1 hour ago, Nick Jones said:

Nothing jumps out.  Not surprised that there was the occasional odd noise and some difficultly getting into gear towards the time of demise.  Could be several reasons for that!

It is perhaps odd that the damage extends to the actual friction surfaces.  The ones I've seen fail from misalignment have tended to be cleaner with the friction surfaces intact and the damage restricted to the blades joining hub and outer ring being snapped.  Does that match your experience Mike?

 

with the herald on both times it was the metal blades  that broke not the friction material. 
I kept the parts they life on the shelf of shame in my garage (along with a broken diff pinion..) and other bits.

I wonder if they is a problem with the pressure plate, I think this wasnt changed, and its putting an uneven load on the clutch plate?

mike
image.thumb.png.2df58704d9e86a141dee33eaa3b8ef7d.png

Link to post
Share on other sites

Yes, that’s more like what I have seen before. Though the additional destruction Pete has is maybe just because one segment held on longer and transferred the forces outwards at that point.

Link to post
Share on other sites

Mike that's interesting to see, I'm relieved it's not completely unheard of.

5 hours ago, mpbarrett said:

On the FWD is the gearbox bolted to the bottom of the engine? if it wasn't sitting flush, or too low or high it could cause the shaft to be misaligned. Or is the input shaft bent or running out of true, that could bend the centre plate and break it. Is the bearing at the end of the crankshaft ok?

The gearbox and diff are in a casing which the crankcase sits on, with the sump being part of the transmission casing. You can't really get alignment wrong, once the 'sump' bolts are all located and torqued. Unless the gasket thickness really makes enough of a difference. See pic below, showing the sump / transmission, which the block drops onto.

FWD_clutch-0285.thumb.jpg.e40a50eb9ac16be35acf14c9f7f71061.jpg

Will check input shaft for straightness. I'll be sad if it's bent cos you can't get them from Canleys any more! Maybe Fitchetts. When you say 'bearing at end of the crankshaft' would that be the spigot bush? Someone on facebook suggested that might be a cause. I'll have a look either way.

4 hours ago, Nick Jones said:

Though the additional destruction Pete has is maybe just because one segment held on longer and transferred the forces outwards at that point

That's what I was assuming Nick. When the AA man turned up I had the clutch cover off, and started the engine to demonstrate what was going on. That resulted in some shrapnel being ejected as the estranged pieces started interacting again. Rather like me and the ex-mrs :biggrin:

I don't really know what to do, apart from check the input shaft is straight. And carry a spare clutch plate and the slide-hammer in the boot so I can change it at the side of the road in 1000 miles time. 

Link to post
Share on other sites

Yes the spigot bearing is what I meant, also I would check (or replace) the pressure plate. if its the same one when the two plates have broken....  Maybe for some reason it putting an uneven pressure force on the clutch plate. Picking at very small straws... :)

mike

 

  • Like 1
Link to post
Share on other sites
2 hours ago, mpbarrett said:

I would check (or replace) the pressure plate. if its the same one when the two plates have broken.... 

Yeah, I meant to ask/suggest that.  Something is strange......

Link to post
Share on other sites
Posted (edited)

Went and did some investigation the other evening, looking for clues. Input shaft appears to be straight, spigot bush is present and feels smooth when I poked my little finger in it! Tried both of my two input shafts in position, spinning them with an electric drill inside the car while watching in the engine bay. Both shafts look straight, and like they go straight into the centre of the flywheel. So not much to go on. I received a new friction plate today which looks better quality than the previous one, so maybe I was unlucky with consistently crap parts twice in a row, or maybe it is the diaphragm (which I will replace).

Another potential problem arose though. The input shaft sits in a bearing at the top of the photo below. The book says this should be shimmed to have 'minimal' end-float. It had more like 'a fair amount'. Maybe that doesn't help my poor clutch, I thought. So I removed the gearbox rear cover to see how many shims were there.

FWD_clutch-7451.jpg.00cee1d8b482bdee74ba0e8807b4b90e.jpg

But was sad to see some little lumps of metal come out in the bottom of the casing.

FWD_clutch-7453.jpg.9888d16eabba3ca22fae0015b0552c6a.jpg

FWD_clutch-7455.jpg.a5a19589521159158487b517492044f5.jpg

FWD_clutch-7458.jpg.d43576a71e50238120567452395d3262.jpg

 

This appears to be what the manual calls a shifting plate, from the synchro unit (no. 88 below)

FWD_clutch-7457.jpg.600898f85a8eab8ca8fbfd2db4f1c4f5.jpg

Wondered whether this damage might have occurred when I was trying to wrestle the car into gear as the clutch was breaking up. It was a pig to get into 1st or 2nd. I don't know anything about gearboxes really.

Will I regret it if I ignore this and just put it back together?

Or rather, would I regret it less than trying to fix it.

 

Edited by PeteStupps
typo
Link to post
Share on other sites

Uh oh....

That would appear to be an FWD-unique design. Not seen in any other Triumph box though there is something similar in VAG boxes I’ve been into.

I would say it quite likely is the result of trying a bit too hard to get gears in the face of a dodgy clutch as I think it’s part of the baulk mechanism. Whether it happened at around the time the clutch gave up entirely or beforehand I really don’t know.

Does it matter? I’m sure it does, but not sure how much. It is one of three by the looks, so if the other two and the spring ring are still in place, it may work a bit. Perhaps more inclined to actually “crunch”.

Given the significant effort (!!) involved in getting in there and sorting it, I might be tempted to invest the relatively minor effort to fix the clutch and see how well it works, and if it works well enough to use, crack on, while keeping an eye out for another box to overhaul and swap in at a later date.

Have to say, if it were mine I’d be taking a tape measure to some of the compact modern-ish 3 pot engine/box combos out there. Always though the FWD was a cracking little car in need of a better power train. TBH it was the desperately short gearing I really disliked. And that loony starter arrangement..... and the clutch..... and rotoflex s..... mine had a somewhat idiosyncratic gear change too..... which may have been related to the clutch oddities.... Full circle!

May the force be with you!

Link to post
Share on other sites

IIRC many FWD’ers prefer to use 1500 gearboxes due to a couple of key parts being a bit more robust and a slightly higher (though still too low to be useful) final drive. There was a guy going by the handle of Yogi who used to pop up on the Club Triumph forum, who had made them his specialty. Had a damson one he daily drove and used to do distance events too. Can’t remember his actual name right now, just that it is something unusual and not unrelated to Yogi.....:confused:

Heralds and Minis have their issues too, and aren’t nearly so nice, exclusive or interesting. 

When I had mine (1990-ish), I really liked the idea of a Daihatsu Charade GTTi power train. 999cc, 100bhp, chippable to 125 or 160.......Tim Styles of TSR was hill-climbing one with great success. They were still new at the time and big bucks. Never did measure one....

Link to post
Share on other sites
56 minutes ago, Nick Jones said:

..and aren’t nearly so nice, exclusive or interesting. 

Ah, thank you that makes me feel more like keeping it! Funny you mention Yogi, my copy of Club Torque arrived yesterday and I checked the CT 'model consultant' page. It's Yossarian something, I will try and get in touch with him. Gearbox rebuild looks like it can be done in situ but WSM mentions some Churchill tools. Plus I am ham-fisted and will probably break more than I fix. 

An engine swap is tempting now you mention it, but this blimmin car has spent 3 of the last 4.5 years in various states of engine rebuild! I could really do with it for ferrying kids around this summer. In fact I could just do without a car that fails catastrophically every 500 miles...

I don't actually mind the short gearing, not much different from my OD-less Spitfire with 4.11 diff. Not great for engine life or fuel economy I suppose, or my hearing. 

There is a bloke on Facebook with a 1500 gearbox, or Mick Dolphin seems to have most of the parts for this one. I'll give it some more consideration. 

Link to post
Share on other sites

Ooh thanks Nick, no that's not the one I was on about. Is that on FB? A bloke near Birmingham has a spare gearbox he reckons is in good condition, which he's offered for free. Which is a price I can't argue with! My brother lives pretty close to brum so am going to try and rope him in for logistics.

Link to post
Share on other sites
8 minutes ago, PeteStupps said:

offered for free. Which is a price I can't argue with!

True dat.....And alot more portable with no engine and subframe attached.

On 3/19/2021 at 2:49 PM, PeteStupps said:

Funny you mention Yogi, my copy of Club Torque arrived yesterday and I checked the CT 'model consultant' page. It's Yossarian something

That's the fella; Yossarian Gaye.  Nice man.  Likes his fwds.  Doing HCRs and the like in one always struck me as particularly dedicated!

Link to post
Share on other sites

Some progress of sorts. Contemplating the effort required to retrieve a gearbox from Birmingham then swap it into my car, I had a sudden urge to investigate the existing box a bit further. A bloke on the helpful Facebook group had just done a gearbox rebuild and said it wasn't too difficult, so what the heck. 

This is how I'd left it. A puller removed the plastic speedo drive gear, then slide hammer to withdraw the layshaft at the top. Then there was a really really awkward sod of a circlip on the mainshaft in front of the big bearing. Probably easy with the right tool but my circlip pliers wouldn't fit so resorted to various screwdrivers. Some blood and swearing eventually did the trick and frightened it off...

 FWD_gbox-7558.thumb.JPG.7a1968547e80c04b264fe50d8983edfb.JPG

Anyway after some more steps forward and backward, I liberated the idler gear (obscured below speedo drive in above photo) and then top gear and 3/4 synchro bits off the mainshaft.

FWD_gbox-7564.thumb.JPG.c6aec80a594b78d1437361ea06c299a3.JPG

 

And this is the resulting pile of debris. No experience with gearboxes but I don't think it's totally dead. The baulk rings don't look badly damaged - just that roller bearing. Hopefully Mick Dolphin or Fitchetts have them in stock. Was thinking I'd broken 1st / 2nd synchro but on reflection, was changing down from 4th to 3rd when this happened and think I eventually managed to get it into 2nd ok. Should have driven home down the A1 in 2nd gear. 

FWD_gbox-7566.thumb.JPG.5b20348e976689964fdd774224527df8.JPG

Link to post
Share on other sites

02.15! That's dedication. I remember nights like that but only vaguely and then try and bury them again.

Just picked up on this thread Pete. Vicariously interesting as my only experiences of the FWD is traveling to Uni as a passenger in a friends 1500 variety. Never driven one.

Very different :laugh:

But certainly beats trying to work on a Mini

Link to post
Share on other sites
2 hours ago, Escadrille Ecosse said:

02.15! That's dedication. I remember nights like that but only vaguely and then try and bury them again.

It's a stupid way to start the working week, I can say that much! But I didn't start til late on Sunday then kept thinking "I'll just get that circlip off and call it a night.." then "...might as well pull a few more bits out now..."

Have ordered replacements of the broken bits, fingers crossed they'll arrive before the long weekend and I won't need to burn the candle at both ends :sleep:

Link to post
Share on other sites
  • 3 weeks later...
Posted (edited)

An update: work was delayed by receiving the wrong roller bearing, although I managed to get the synchro hub back together

FWD_clutch_Gbox-7620.jpg.127b013048113866d3af263e240b373d.jpgFWD_clutch_Gbox-7631.jpg.3beb6e1921bb747cd9c80ea30b8f82e6.jpgFWD_clutch_Gbox-7633.jpg.4a7cbeb128f7b41411da7ca0c29f2ecd.jpg

Also for the first time i my life I bought some proper gasket paper (3 rolls of various thickness) and hole punches, so was able to waste time drinking lager and making gaskets

FWD_clutch_Gbox-7696.jpg.ab30dbcc8e9ceae656ab64d770774736.jpg

Eventually the right bearing arrived and I went through the workshop manual and tried to do everything properly during re-assembly, which I skipped last time... 

FWD_clutch_Gbox-7703.jpg.3046eb79adf86c20ec30a9f16cc44079.jpg

Getting the laygear cluster into the gearbox was a real struggle. It's the bottom set in the photo below, viewed from below the dashboard. You have to reach into the back of the gearbox and stick the thrust washer in position with grease. Then feed in and offer up the layshaft and gear cluster to mesh with the mainshaft gears, and slide the layshaft into its hole without disturbing the thrust washer, all while only being able to hold the shaft from one end. Awkward but eventually accomplished. I'm not religious but couldn't help thanking every available deity when it finally went into place. 

FWD_clutch_Gbox-7705.jpg.f4eafb1b6070841c387d873b6007b0d8.jpg

 

 

Edited by PeteStupps
Delete photos
Link to post
Share on other sites
Posted (edited)

With the gearbox back together I contacted Yogi the FWD expert about the original clutch breakage problem. Very helpful bloke! He suggested two possibilities: bad luck, and the spigot bush being seriously worn, allowing the input shaft the flex and cause misalignment.

This was the 3rd person (thanks @mpbarrett above) to suggest the spigot bush so I finally began to pay attention...!

Took the flywheel off and removed spigot bush. Tried it on input shaft tip: wobbly. Turned it over so shaft went into unworn end: not wobbly. Went back and looked at previous engine which killed one clutch plate and put 500 miles on the replacement: no spigot bush. I rebuilt that engine and don't remember ever seeing or placing a spigot bush in the end of the crankshaft. If there was one there when I started it must have fallen out at some point and never been replaced. 

I think that might have been the problem. Have ordered a new spigot bush from Fitchett's.

Edited by PeteStupps
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...