invacar LightBulbFun's Invacar & general ramble thread, index on page 1, survivors lists on Pages 24/134 & AdgeCutler's Invacar Mk12 Restoration from Page 186 onwards, still harping on...

[LightBulbFun]

3 hours ago, LightBulbFun said:

so I am little bit stuck as to what to do now, as it clearly wont be a simple case of chuck a new drive belt on as I had hoped, I suppose the fix from here would be remove pulleys, somehow straighten out the gear-selector rod and fit new pulleys with new belt

alright having given this a bit of thought, and realising @Zelandeth's CVT system doesn't even have the lock washers im worried about so if I cant salvage the existing ones ill just do as he did and apply a bit of loctite  

https://autoshite.com/topic/29443-zels-motoring-adventuresvolvo-renault-rover-trabant-invacar-a-sinclair-c5-updated-3003/page/149/#findComment-2612460

 

I am thinking with this, plan, with my brother coming in the 10th, ill try our collective bests to remove the old pulleys, and if thats successful then try our bests to fit a new set of pulleys and belt, (either on the day or sometime later depending on when I get the pulleys in hand (as they are not kept at the house)

the bent gear-selector -rod does not prevent the selection of drive or reverse etc, so I think ill just live with that, until such time as I can get REV to somewhere where that can be sorted. (although I do have concern over if the bent linkage putting any undue stress on any internal parts of the gearbox or not)

I have a commitment I am really hoping to have REV sorted for on the 25th of April, its that gathering of lighting enthusiasts/collectors at a good friends place in kidderminster that I have mentioned beforehand, the last one was in October and I did not quite have REV back in time for that one, so I already pretty strongly committed to the one in April so I would hate to let him down as he has been wanting me to attend for many years now and I have otherwise been unable to due to lack of personal transport etc

 

 

 

[Dobloseven]

Do the pulleys slide on,or are they on a taper?Is a puller needed?Best of luck with it anyway,those pulleys look well rusty and can't have done the belt any good.

[mintwth]

15 minutes ago, LightBulbFun said:

I do have concern over if the bent linkage putting any undue stress on any internal parts of the gearbox or not

How's the linkage connected at either end? 

If it can be removed, then it should be easier to straighten (or to take it somewhere to get it straightened). 

[LightBulbFun]

11 minutes ago, Dobloseven said:

Do the pulleys slide on,or are they on a taper?Is a puller needed?Best of luck with it anyway,those pulleys look well rusty and can't have done the belt any good.

Page 55 incase anyone wants to follow along at home so to speak  

https://zelandeth.org/cars/ac-model-70/DHSS-Workshop-Manual-For-The-Model-70-Three-Wheeler.pdf

the rusty pulley surface actually felt pretty smooth despite the looks  (although I did not spend long in there when I suddenly realised it was in a jammed state and could potentially snap closed at any provocation!) but as you say having a fresh set of pulleys in and of itself wont be a bad thing  

Just now, mintwth said:

How's the linkage connected at either end? 

If it can be removed, then it should be easier to straighten (or to take it somewhere to get it straightened). 

excerpt from one of @Zelandeth's posts that shows how it goes together, tho looking at the angle his is sitting at, perhaps is not as badly twisted was I thought, but ill have to try and get a picture of it

On 11/08/2020 at 19:38, Zelandeth said:

The gear selector was originally attached to the selector arm on the box by a roughly 1/4" diameter roll pin, held in place by a split pin.  I was missing this because the replacement selector I fitted (the original one in TPA was totally siezed) didn't have it, and no amount of effort was able to shift the original one from the linkage.  Originally I fitted a bolt in this location and used a locknut arrangement to try to stop it loosening itself over time.  Apparently this didn't work as since then I've lost two bolts.

Annoyingly the replacements I have, presumably because they're a metric size, don't fit.  The smallest size I've got that fits drops straight through, the next size up won't fit.  Adding an extra washer to the smaller one adds enough length that I can't then get the split pin in.  So we will need to use a bolt then for the time being.

It was at this point I had a bit of a brainwave.  There are two pivot joints on the gear linkage of this type.  The lower one (the source of my problem), then an identical one where the rod actually pushes/pulls on the actual gear selector on the box.  The lower one is an absolute swine to get to other than from underneath because there is a load of pulley and belt in the way.  The top one however is near enough level with the top of the gearbox pretty much and is readily accessible.

So I took the standard coupler out of the top pivot and installed that in the hard to get to bottom location.  I then fitted a bolt and lock nut to the top one.

The fact that I can actually get to it makes it possible to easily do the locknut up *way* more tightly than I probably managed last time.  I also put a blob of thead lock on it. 

At least if it does drop off again in future replacing the thing will be a five minute job as it's dead easy to get at.

 

[Zelandeth]

 

10 minutes ago, mintwth said:

How's the linkage connected at either end? 

If it can be removed, then it should be easier to straighten (or to take it somewhere to get it straightened). 

I suspect that the linkage rod will be sortable just by physically pulling on it - I don't remember them being particularly substantial.  The bendage will almost definitely just be from getting whacked by the belt when it let go - fact that it runs within the safety cage around the belt means it's very vulnerable to that.

22 minutes ago, Dobloseven said:

Do the pulleys slide on,or are they on a taper?Is a puller needed?Best of luck with it anyway,those pulleys look well rusty and can't have done the belt any good.

They're straight shafts with a keyway - and as I recall a non-captive key which can and will make a bid for freedom when the pulleys are removed.  I seem to recall getting the one on the primary to line up properly when putting it back together involved a certain amount of swearing as well.

Between bits of belt having got in there and potentially having been subjected to and over-speed when the belt snapped (the primary is only rated for 5,000 rpm), it may just be stuck and need a bit of persuasion to move back to the rest position.  I'd give the primary a bit of a poke and prod and see if you can get it to reset without removing it if possible.  Primarily because I remember getting the bolt out of mine being an absolute PAIN.  It was absolutely wicked tight, and there's really no good way to lock the pulley in place.  Ideal situation is to get an impact gun onto it which I don't doubt would shock it loose in moments - but you can't because the bulkhead is in the way.  This also makes properly tightening the bolt when the new pulley is on equally difficult - the bolt in the primary of mine managed to work itself loose at some point, which I was alerted to by a jingling noise at low speed which turned out to be the washer under the bolt.  Even with Locktite in there I still don't fully trust the bolt to stay put.

Those locking collars however look to be the ideal solution - I don't have those!  So long as they don't get physically broken when removed those should be fine for reuse as they just slot in place over the bolt once the pulley has been secured and then bolted down.  I may have to look at coming up with something similar in the future as I really don't trust those bolts to stay in place without them, and had always wondered if i was missing some locking hardware.  Turns out I am!

Secondary is far less of a pain to remove simply because it's directly coupled to the wheels, so by having a helper hold the brakes firmly on it's easier to actually apply force to.

In your case I'd be seeing if you can get the bits of belt out of there and get the primary to reset properly and if so just concentrate on changing the secondary.  "fairly smooth" really isn't good enough in this case, the pitting you can see there definitely will have been causing excess drag and overheating of the belt at speed.  That may well be where the bit of missing performance you'd been looking for was hiding - it was like night and day when I got the new pulleys on TPA.  It will also affect how willing the belt is to move fully down into the groove which may well throw the gearing curve off.  There's a lot of energy being transferred through there and this type of setup is horrendously inefficient and lossy at the best of times, so any additional friction is bad news.

If you can get the bits of shredded pulley out of there and make things move again I'd not discount just slapping a new belt on for now to get you mobile again though - it's something that is definitely needing to be changed, but the original belt (which may well have been compromised to start with given we don't know its age or how it was stored or how worn it was to start with) lasted this long, so if you need to get the car to somewhere to have the secondary pulley swapped over I'd consider that to be a viable option.

[mintwth]

22 minutes ago, Zelandeth said:

suspect that the linkage rod will be sortable just by physically pulling on it

Worth doing before going on a long drive? The bend must change the travel at the gearbox end (since a bent linkage will effectively be shorter than a straight one) but might not be enough to matter

[plasticvandan]

Seems a bit daft putting a new belt on rusty pulleys,especially if you have new ones.the old ones could then be skimmed perhaps and kept on the shelf. You already know the answer to the gear linkage,straighten it out. Maybe one for a garage to do.

[Yoss]

I've liked rather than sad faced your breakdown post for the simple reason that it all seemed like a relatively painless affair on a nice day. We've all had our first major breakdown and they don't all go as smoothly as that. 

I was daft enough for the first couple of years of driving to not even have breakdown cover. And I was driving around in 25 year old Triumph 1300s. Your weakness is CVT belts, mine was input shafts. They're just not up to the job. First time one went I was on my way home from a BMC Farina pub meet. You just go to change gear and suddenly you have no drive. Fortunately a friend was just behind me so he towed me home in his Wolseley Six. 

You can sit there selecting gears without using the clutch because the engine is no longer attached to the gearbox. So it's basically the same problem as yourself but for different mechanical reasons. 

Look at this. 

Three Triumph FWD input shafts. The first has snapped at the circlip groove. The second the spines have stripped. The corresponding splines in the input gear  will have done the same and so the shaft just spins and the car goes nowhere. The third is the uprated 1500 shaft with longer splines plus they moved the circlip groove to the sensible end. It was ridiculous to expect 75hp in the 1300 TC to go through those short splines and putting the circlip groove at that end was ridiculous as all the power of the engine has to go through that before it can even get to the inadequate splines. 

The 1500 design is much better though you have to change the corresponding gear in the gearbox that the shaft sits in too. I put the whole 1500 gearbox in mine. But that's still not the end of the problem. I was overtaking a car on the A30 near Shaftesbury and when I changed back up in to 4th gear there was a bang and loss of drive with all the symptoms of input shaft failure. Obviously ever since the early days I've always carried a spare shaft in the glove box as you can have the thing out in 10 minutes. So whipped the shaft out and it looked fine. So the clutch came out next, which is only another 10 minutes once you've got the shaft out. 

Can you see the problem? 

What with that and the Rotoflex driveshaft couplings the whole drive system isn't really up to the job so I feel your pain. Doesn't stop me using it or worrying that I might not get where I want to be. You just deal with it when it happens. 

[plasticvandan]

Wouldn't be surprised if that is the cause of the belt failure if that silver bit really is the jagged remains of the pulley face,those pulleys are toast.

[BorniteIdentity]

On the basis that you’ve had one high-speed grenading rubber issue, it’s worth checking your tyres too. Were they replaced when it was recommissioned? Date codes are worth checking…

[Zelandeth]

1 hour ago, plasticvandan said:

Seems a bit daft putting a new belt on rusty pulleys,especially if you have new ones.the old ones could then be skimmed perhaps and kept on the shelf. You already know the answer to the gear linkage,straighten it out. Maybe one for a garage to do.

Absolutely agreed.  I'd definitely say change it - Just saying that if push comes to shove and the car needs to get to a garage to have it changed if it can't be done at home, I'd not be too worried about driving across town if it came to it.  If of course things can be unjammed, if not it's a pretty moot point of course.  It really does need to be changed though.

The primary pulley sheaves are aluminium so tend to fare better over time than the steel ones on the secondary.

Pulling the secondary pulley apart once it's off the car and refacing the sheaves shouldn't be too difficult I'd think, but admittedly I've never tried!  Can't hurt to keep usable spares if we can though.