speedo drive

[Richard Fridd]

i have fitted a new speedo cable recently to my fulvia s1 but there seems to be a problem with the squared end of the cable making a good connection with the drive from the gearbox.has anbody have experience of this problem or does anyone have a temporary solution?all advice appreciated.

[rogerelias]

Do you mean the square end of the cable is too small where it goes into the box?

[Richard Fridd]

it seems that way.not sure if the wear is on the cable or in the hole

[rogerelias]

If the cable square is worn, what you could try is heating the square and melting solder or brazing wire over it and filing down to suit fitment.

[Scarpia]

is the screw "outer fastening" the same "depth" so the square inner cable is fully engaged in position in the speedo?and is it fully tightened up?

[Richard Fridd]

i am fairly sure the inner cable is engaged.i will have another check and then remove the gearbox output drive to have a closer look if i can.

[Richard Fridd]

i have had a closer look now.no definate problem visible so have used some electricians shrinksleeve at the end of the inner cable to achieve a good connection.

[ColinMarr]

Hi Richard,

I would be interested to know more about how you got on with this. I may have a similar problem. My speedo started to fail intermittently, which I thought most likely to be a fault in the instrument itself, but this seems not to be the case. The cable looks to be OK with the square ends not showing any signs of slipping. I wonder if my problem is to do with a fault in the drive coming out of the gearbox, which in my case is Series 2.

Have you managed to pull the drive unit out of the gearbox with the gearbox in-situ? And if so, is it repairable? I have got as far as undoing the 10mm nuts that seem to hold the drive connector onto the gearbox, but it doesn’t want to respond - should it just pull out? Oh for a fully working speedo!

Best wishes,

Colin

[Richard Fridd]

hi colin,i did manage to remove the output assembly completely .the reason mine would not come out easily was mating faces stuck together with the associated gaskets.once seperated the assembly can be pulled out in a similar way to the distributor assembly.the repair has been sucsessful so far.i can send you some shrinksleeve if you can remind me of your address.it is a 10 minute job to fit and test instead of the 3hr exercise i opted for with spanner,lever and circlip pliars .best regards richard

[ColinMarr]

Thanks Richard,

Yes please, a small piece of shrink-sleeve would be much appreciated – the address is 3 Methuen Park, London N10 2JR. Does it need to be heated to shrink it?

I hope this works because I dread trying to get the drive out of the gearbox in-situ. In my hybrid car the drive output is just below the bulkhead and there’s not much room to get at anything. I suppose these things are sent to try us.

Happy motoring,

Colin 

[Richard Fridd]

i will post some to you tomorrow.just slip it over and heat it with a lighter or similar.best of luck!

[ColinMarr]

Happiness is a sweetly swinging speedo!

Thanks again Richard. I tried the shrink-wrap and to my amazement it seems to have worked! Both ends of the speedo cable were ‘square’ without any sign of them turning/ slipping and I fitted the shrink-wrap very sceptically. But lo and behold it works!

All I have to do now is check it up to 140 mph, which living in London might take a day or two, but I’m confident all will be OK

Colin.

PS: I was only kidding about 140 mph, but as you can see, it does work:

[ian]

You obviously had a small rear seated passenger to lean over you to take the photo DIDN'T YOU Colin

Just how accurate is your speedo Colin ?(and others) I  have yet to check mine at the higher speeds

[ColinMarr]

Yes, of course the photo was taken by a miniature person sitting on my right shoulder. It would be quite irresponsible for me to use a camera single-handed while driving at any speed!

Speedo accuracy is an interesting question.

My car started off in 1967 as a 1.3 Zagato Sport with a four-speed box, skinny wheels (145SR-14) and a 120mph speedo. The Oude Weernink book shows this should have had a final drive of 10/37 giving it 18mph per 1000rpm in top gear.

My car now has a 1600cc engine, five-speed box from a 1600 Sport, runs on alloy wheels with 175SR-14 tyres and has a 140mph speedo. The book shows the 1600 Sport had a final drive of 11/39, which on 165-14 tyres gave it 19.9mph per 1000rpm in top gear. The same final drive ratio was used in the Flavia 2000 coupe HF, which on 175-14 tyres gave it 20.3mph per 1000rpm in top. It is this latter figure that should apply to my car.

It is this unusual combination of high final drive ratio and large tyres that give my car such long legs, which makes it a touring car compared to the short legged sprinting quality of the coupe. I like it that way.

As to accuracy, all I can say is that I have checked the mileometer against motorway mile-posts over a 100 mile stretch of the M4 and it is accurate to better than 1%. It’s not easy to verify the accuracy of the speedo itself, but I have always thought that mine might tend to under-record because of running on larger tyres/ wheel diameter than intended. It looks to me that my car does 21.2mph per 1000rpm.

Incidentally, I have experience of four different Fulvia non-metric speedos, from early 120mph units and later HF 140mph units – they were all marked “1610 revs = 1M” (Mile). This suggests that Lancia simply ignored the errors that would arise from different wheel and tyre sizes!

Colin

[ColinMarr]

Ian,

I was interested in your question about accuracy of speedos and tried to answer it. Sorry that the thread seems to have died – I hope my response didn’t kill it! I don’t own a GPS/ Sat-Nav and haven’t had the doubtful pleasure of using one in a car old or new, but I learn that these devices also give an accurate indication of road speed.

I reckon there are lots of forum/ Fulvia owner contributors who have GPS, who could give us their knowledge. But, maybe (like me!) they just want to believe what their Veglia Borletti instruments tell them.

Colin