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MG Midget and Sprite Technical - 1.75' SU Throttle Cable Retention
|Or lack of...! Car passed it's MOT a week last Friday, pulled out from the garage with the MOT paper on the passenger seat and 100 metres down the road the throttle pedal flopped onto the floor.|
Turns out at some point I thought a rubber grommet was sufficient to stop the cable outer from pulling through the bracket - I'm blaming that on my naive 24 y/o self from 12 years ago. Trusty cable tie got me home.
So what should actually be there? I can't see any literature that shows me what stops the cable outer from pulling through. I'm not certain what car the carb/throttle linkage is off, so not sure where to look.
|Subject heading should of course read... 1.75" SU Throttle Cable Retention.|
That would otherwise be an abnormally large carburetor.
|Probably a threaded cable adjuster like this https://www.beedspeed.com/cable-cable-adjuster-p-1441.html?osCsid=tiaaatuebjgm8mkldg5amvuge4|
|Well if it were off a Metro it should look like this:|
Yours look quite different to the Metro one, in fact it's on the opposite side of the carb. I'm sure a threaded adjuster like Dominic suggests will work and also make it easier to set up the free play.
|It's an HS6 carb, if that helps. Manifold is from an MG Metro.|
I believe that you are missing the plastic fitting that fits into the angular bracket attached to the side of the carb.
The plastic piece is somewhat tubular with a flared skirt that prevents any cable sheath from passing directly thru the larger hole in the metal bracket.
It appears to function as both a “stop” and a “guide” for the accelerator cable.
Without something that can replace this item – your accel cable may pass right thru the bracket opening. The cable tie solution serves to hold the accel cable sheath in an approximate vertical position. Probably not a long term solution.
Perhaps some one will come along who also has a metal lathe could produce this item with a narrow upper tube and a flared skirt to hold it against the flat bracket.
On the other hand, my HIF44 and Titan manifold arrived intact with all fittings BUT may be radically different from your set up...
Hope this provides some insight into a solution for your vehicle...
|On another point, is there any sort of heat shield between carb and exhaust?|
|OP I can probably help you here as I do have a Lathe, so will happily make you one.|
I didn't have the lathe when I needed to cobble something together for my single carb set up, so I drilled a hole through a suitable nut and bolt and got round it that way. . . .
let me know if I can help
|Think Domonic's suggestion of a threaded cable adjuster looks about right. I'll check the outer diameter of the brass cable outer end bit and see if I can find something on Ebay.|
Good spot Nigel - Anthony Cutler (whom I bought the engine/gearbox off many moons ago) mentioned at the time that the inlet manifold had been Camcoated (a ceramic coating by the looks of the Camcoat website), to prevent heat transfer from the exhaust. As a result I don't believe he had any issues running it without a heat shield.
Thanks for the offer of turning a small ferrule for the cable outer PB - very generous of you, but I wouldn't want you to go to any trouble - it's not exactly a 5minute job. If I can pick up a part on Ebay or suchlike then I'd rather not cause you any hassle. If I can't find anything in the next couple of days then I will take you up on the offer and make a donation for your generosity and time!
|I probably have an adjuster or two in the Shed. They came with the Venhill cable kits I bought, but I didn't use them because they're metric and I preferred to reuse the original imperial threads. |
I'll have a looksee in an hour or two and you're welcome to an adjuster if there's one handy and it helps you.
|On mine I used a male brake union. It fitted neatly into the hole and I secured it with a thin nut. The cable outer locates snugly into the brake union.|
|Neat solution Rob. |
However, here's what I fished out of the box. Any use to you? If so txt an address to 07541162132 and I'll drop it in the post.
|Only place to find metric threads in my garage is in the trash bucket. I find them a lot when doing other cars, and always replace with the correct item, and then check every nut and bolt left over for their thread before returning them to the relevant drawer just so i don't get any metric immigrants! Tidying up is then accompanied by a regular tin as the offenders land in the stainless steel bucket.|
As John says, having a threaded adjuster makes setting free play a doddle. Always use a ferrule on the end of the sheath, as I have seen a fair few where the plastic coating rumples up and the outer cable is then small enough to start feeding through any stops, with resulting lack of operation.
Here is another picture of a HIF44 set up. You can see that the accelerator cable has a large plastic thingy that clips into a slot in a bracket. Having said that, this is not longer the case on my midget as I found the Metro cable a wee bit short and so I used the cable adjuster off the end of a 1500 throttle cable (it looks rather like that in Greybeards photo).
|Thanks for the photo Chris, does the bracket that the white plastic piece fits in come off your Titan manifold?|
I've found the following parts on Ebay:
Second one looks like the one Greybeard was very kindly offering, the first one looks to have a handy knurled nut for adjusting the free play. I'll probably go for the first one.
Thanks for the offer of sending that up to me Greybeard, you're very generous. I wouldn't want you to go out your way though so I'll pick this one up off Ebay. Maybe I can return your offer at some point by helping you out with a part (though I'm guessing you have a lot more stuff in your garage than I do!).
|»(though I'm guessing you have a lot more stuff in your garage than I do!).«|
--Because my trash bucket is under-utilised LOL!
I just noticed my adjuster is missing its locknut. But that's okay - I have some redundant M6 nuts that I have failed to throw away.
(Just teasing, Dominic)!
No prob, Robin. Good luck with it.
|If there is a Halfords near you, they do something similar:|
The bracket for the throttle cable is part of the heat shield so is clamped between the carb and the manifold (it also provides the clamp/clip for holding the choke cable).
I notice in your photo that your cable attaches to the opposite site to the Metro and this may be part of the problem as there may not be an appropriate heat shield.
|Ummm - not sure about that one Jim, no offence intended. It would need either a 7mm thread in the cable bracket or a 7mm locknut to function as an adjuster. And 7mm nuts are not terribly common. |
Both the parts that Robin posted would also need locknuts (6mm) to function as adjusters because there is no thread in the SU cable bracket, but at least 6mm nuts are as common as daisies. Also the one with the knurled nut is listed as out of stock. Did you buy the last one in the world, Robin :-)
Agree with Dominic that a ferrule is near-essential. For one thing it stops the cable sheath trying to twist during adjustment. You can see one in my paw next to the adjuster.
|No problem Greybeard, though to be fair I think that Halford's photo is very poor and I believe the locknut is there, but it's shown tightened down to the 'cone' part of the barrel. Both the barrel and the locknut have a slot cut in them so that the adjuster can be fitted onto the cable without the need to remove the clamp at the end.|
|I think you're both right - there would appear to be a locknut on the adjuster, as the slots aren't aligned. However, as Grey said, you would need another locknut, as the bracket isn't threaded, whereas a bicycle brake lever assembly would be.|
|Dave O'Neill 2|
|Sorry Greybeard - I see your point - there would need to be 2 locknuts to form an adjuster. Simply buy two barrel kits? Though the Halfords one doesn't look very long anyway, so there wouldn't be much adjustment.|
|I've just googled 'm7 half nut' and come up with this website. |
It appears that they also have quite a range of imperial fasteners.
|Dave O'Neill 2|
|Dave and Jim - both right. I totally missed the fact that the wire slots were out of alignment. Oops. |
However I went to the Shed about half an hour ago to have a cig and look for my reading specs and I spotted this that I had completely forgotten about.
MGOC spares scheme throttle cable complete with the correct 1/4" threaded adjuster. It was on my car for about a week until I fitted the Venhill cable. I don't want it so it's up for grabs (free) if anyone wants it.
The adjuster in my earlier photo doesn't have a wire slot but (a) that could be fixed in about a minute with a hacksaw and (b) Robin wouldn't need a slot as there is no nipple on the end of his wire.
This is fun!
BTW that looks like a useful site Dave.
|Darnit - went to order it this morning and only then noticed it was out of stock!|
Agreed, the second nut would be required to lock the adjusting nut into position.
Greybeard - is the ferrule in your hand in the first picture performing the same function as the brass ferrule that's already on my cable?
Looks like I'll be going for the second eBay option, with the addition of an M6 nut to lock against the first one. I'm siding with Greybeard on having a dislike for metric fasteners on an otherwise imperial car, but I doubt this will be the first metric fastner to make an appearance on my Sprite!
Good observation RE: the slot and nipple (that could be the band of a pub?), hadn't appreciated the slot would be required to allow the assembly to get past the cable nipple.
One possible spanner in the works that I'm going won't bite me in the bum - there's not much clearance between the bonnet and the carb, so with the extra height added to the throttle cable, will there be a risk the cable will get bent when the bonnet drops? I think it'll maybe just be OK. Only one way to find out!
Greybeard - is there a nipple on both ends of that throttle cable? How does it pass through the footwell/ bulkhead otherwise?
|Yep there is a nipple each end of my redundant cable. Doesn't matter as it passes through the bulkhead and engages in the pedal without difficulty, at least on the 1500s pedal. I understand many A series cars have 1500 type pedals fitted as for whatever reason they are felt to be a better design. |
You are right about the vertical clearance too - that worried me a little bit. On my car at least the cable termination meets the linkage horizontally and there is a bell crank with a link rod down to the throttle shaft. Different to your arrangement.
No, you should not need a separate ferrule if your cable sleeve has one already.
As you appear to have no nipple at the carb end the slot is unnecessary to you. You could simply thread the adjuster over the wire. Easy peasy.
|Just to report that I've fixed the throttle cable retention issue with the cable adjuster I bought off Ebay. |
Wasn't sure about the need to use it an as 'adjuster' though, I just pulled the throttle pedal back and pulled the cable until it was tight but not actuating the linkage and then clamped the cable down. Seems OK?
Only problem is when you manually actuate the throttle at the carb end, the cable pops out the adjuster cup and the throttle sits open.
The cable certainly doesn't appear to sit snugly in the adjuster cup, but it's better than the cable tie that was holding it before! We're making progress.
|Robin, well done, it generally looks good.|
>>Only problem is when you manually actuate the throttle at the carb end, the cable pops out the adjuster cup and the throttle sits open.<<
I think that possibly happens on most(?) (all?) set ups - but I could be wrong, often am.
As soon as I saw your photo I thought I didn't like the ferrule sticking up - you could cut a bit off the bottom of the narrower section of the ferrule so it sits more in the adjuster or if the wider section of the ferrule fits inside the adjuster then cut all of the narrower section off.
If it was my car that'd be on the to-do list and it's priority would be low so it'd only get done when I was putting off a more important job that I don't want to do. I keep thinking about getting a ferrule with bend for mine but have yet to get a roundtuit.
|Thanks Nigel, I wasn't too happy with it sticking up so much either, but it'll get me to my wedding using wedding cars sevenoaks in 4 weeks time (Hopefully!).|
If I cut the narrow section off, it'll fit much nicer, for sure.
Now for all those other jobs...
|If you do cut the narrow section off, the ferrule might not stay put.|
|Dave O'Neill 2|
|I use a bicycle brake cable adjuster|
|What makes you think that Dave, it looks deep enough and would be a snugger fit, there's not that much slack on the inner cable (well there's isn't on mine, perhaps why I sometimes kangaroo on bumps), I've obviously forgot or don't know something, again.|
This thread was discussed between 05/06/2017 and 20/06/2017
This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.