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Ferret tachometer cable

Mad Scientist

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Hello folks,

Can someone please help me locate the Ferret tachometer cable NSN - I need to replace my broken one. I think they are 11 feet long.

Any information appreciated on the type of termination at each end, so that I can get the correct cable made up.

Many thanks, Mad Scientist

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4 hours ago, Diana and Jackie said:

You can get one made if needs be 01639 732300 Speedy Cables (london) who are not in London but just up the road from me 🙂


Just be aware from experience that "Speedy" is the name of the business, not their modus operandi ...  🙂


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  • 1 month later...

Thanks to support from Paul McNeill in Canada, to Clive for NSNs and others on this forum, I managed to fit a new tacho cable in the Daimler Ferret this week. Here, based on Paul’s advice with what I learnt is a summary for others to follow. You can get a sealed replacement cable from Speedy Cables. The price was £65; with carriage and VAT the total was £93.54. A very good price and excellent service from Speedy. Speak to Darren, or quote my invoice No. 29368. Delivery was the next day by UPS.

The standard cable is 11 feet. On Paul’s advice I got one made up with an extra 4 inches. Actually, 11 foot six inches wouldn’t go amiss. Original NSN for the complete unit = 6680-99-802-0231, just the inner is 6680-99-802-0251, not that Speedy needs this detail. The black heavy duty casing Speedy makes up is slightly smaller diameter than the original, but looks the same. The casing is T6LA Heavy Duty Conduit. You want to ask Speedy for the following ends when ordering: Drive End = Bentley Fitting; Instrument end = AT Connector. Unlike the original, the cable is sealed, so there is no need to try and grease the inner. At the B60 engine end, the nut is 1” AF, not 1+1/8th inch AF, as on the original, but otherwise the thread pitch is the same.

I dealt with fitting the engine end connection first. Tape the cable below the nut, or use a plastic clamp, about 8" or 20cm from the end of the cable - this is to ensure the threaded nut that secures the cable to the engine does not inadvertently slide down the cable into the engine compartment bilge causing you to utter expletives not normally heard in polite company. It would be a nightmare to retrieve it. It also means the nut stays in position as you feed the cable past the gearbox and under the petrol tank into the engine compartment. At this point I needed assistance for someone to push the cable while I used a coat hanger wire hook to hoike the cable+nut up to grab it and pull it into position in the engine bay.

As Paul says in his remarks to me: I tied a length of line to the tool I was using and the other end to me, so I could retrieve the tool if I dropped it. You have to remove the two bolts holding the engine breather tube in place. Don’t undo the single nut holding the other end of the breather tube in a jubilee/hose clip. It is impossible to replace, working through the rear inspection hatch into the engine bay. Rather, work the breather tube out of the way. Also, I found it necessary to remove one of the engine case covers. That will allow you just enough space to get at the original 1+1/8th inch AF brass nut. Lubricate the cable end where it engages the engine with a quality gear grease.

I fed the cable in from the fighting compartment. You’ll need to remove the gearshift lever and its casing from the hull wall. Remove the split pin and disconnect the Clevis pin from the first knuckle joint. No need for me to tell you that gravity is not your best friend in a Ferret, especially when you’re tired and your hands ache. Also disconnect the speedometer cable as it goes into the gearbox. This will allow you to remove the right-hand transmission cover/tunnel. Take up the floor pan, the jump seat (if fitted) and the gunner’s seat. Dismantle the cover around the gearbox, remove the oil filter and any radios to allow you free access to thread the cable by the right hand battery and into the engine compartment. It helps to cable tie the new tacho cable to the support for the gearbox control rods that sits by the battery tray. This keeps the tacho cable away from the spinning prop. shaft. Thread the cable up by the side of the petrol tank, and here it can be connected to the engine case, as above. I found the cable naturally curved neatly around the side of the engine bay and under the petrol tank.

Check the cable that the turns are not sharp, and the cable is clear of the prop. shaft, gearbox and handbrake controls rods. There is a fairly tight turn as the cable exits out from under the floor pan and by the hole in the transmission cover/tunnel enabling the cable to lead up the wall between the fighting and driving compartment areas. At this point the cable can be led with the speedo cable around by the electrical connector holder, down by the steering gear casing, and into the back of the rev. counter on the instrument panel. Make sure the cable goes above the electrical connecter cluster underneath the instrument panel. I managed not to feed it through the small gap between the steering gear casing, but you can work out what’s best for the way your Ferret furniture is configured.

B60 engine drive end Bentley fitting.JPG

Tacho cable instrument end AT connector.JPG

Taped nut.jpg

Engine case cover.jpg

Breather pipe removed.jpg

Cable tie.jpg

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  • 5 weeks later...

An update to the post about fitting a new Ferret tacho cable.

I said in the earlier post above “You have to remove the two bolts holding the engine breather tube in place. Don’t undo the single nut holding the other end of the breather tube in a jubilee/hose clip. It is impossible to replace working through the rear inspection hatch into the engine bay. Rather, work the breather tube out of the way”.

If you do (as I did) unwittingly remove the nut and bolt holding the clip for the engine breather tube in place, only to discover later the magnitude of effort involved in its replacement, well, you have two options.

You can either (a) get a very small child of great intelligence – preferably one who is chimney-sweep time-served – and explain to said minor with hands sufficiently small to get both of them through the underside inspection hatch that the nut and bolt needs to be screwed into the engine frame in a manner that you cannot do without otherwise removing the two oil hoses that obscure the operation from above. I guess even to contemplate this option in the crazy PC times we live in, you will have to jump through all sorts of hoops, get CRB checked and the like plus bribe any parents or chimney-sweep master.

Or (b) you fit a self-tapping bolt in place. Thanks to my friend Clive (not Clive E, ever helpful tho’ he is) but the one that helped both myself and Paul MacN, this was accomplished with much less effort than trying to fit the nut and bolt from underneath with rat-tail pliers and forceps and much swearing.

As a temporary wedge I used the hard plastic jaw protector from my bench vice. This forced the clip at the end of the breather pipe away from knocking on the bevel box and against the engine frame. Don’t be tempted to use a clothes line peg, or any similar sprung clip. It will assume a life of its own and drop into the engine bay, probably never to be retrieved.


From underneath, through the inspection hatch, Clive used a dental pick to line up the hole in the engine frame with the clip. He then used pliers to force the backplate of the self-tapping bolt (Duratool No 8 captive ‘U’ nut) onto the ridge of the engine frame. At this point re-check the alignment with the dental pick, or similar. Clive then used a pair of my forceps to ease the bolt into the aligned hole first of the clip then into the backplate/engine frame. Once that was done, he used an 8mm ratchet spanner to hold the bolt in place and a pair of pliers to hold the backplate in place on the engine frame.

It was then a question of patience, and very small turns of the spanner until the bolt bit into the backplate and held. After that, it was just a question of tightening the bolt. The clip had bent slightly (which you might just be able to see in the picture), so the breather tube didn’t sit entirely against the engine frame, but the important thing is that it is clear of the bevel box, and not rattling against the case of the bevel box.

Duratool nut.jpg

Duratool No8 self-tapping bolt.jpg

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i'm used to the maintenance british military vehicles being for the bloody minded and those of a masochistic nature.  but this activity seems to have been designed by a particularly skilled sadist determined to break the will of anyone foolish enough to want to own a ferret 🤣😂

congratulations on beating the 'designer' on this one and thank you for sharing the 'kowledge'


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