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PaulAA

LHD carb throttle linkage

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A small tip for other Stromberg / SU owners... having struggled with a clunky, grinding throttle linkage for years and contemplated various hair-brained schemes for partial or full replacement with a cable connection, I dismantled the three ball connections on the mechanical linkage last night, cleaned them up, replaced the springs and packed them with grease.

How could I have failed to see the obvious for so long?  The transformation is stupendous - silky-smooth pedal operation, even without the impossible-to-fit nylon bearing supporting the pedal rod penetration through the firewall.

Less than an hour well invested, most of which was spent trying to get the cotter pin back into the bottom retaining screw, blind and covered in grease.

Paul

Edited by PaulAA

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On a similar vein, I snapped the throttle cable on the Vitesse a couple of days before MIRA the other week, fortunately had a spare so no delays. However yesterday evening given that I have a MJ "tuning?" session coming up, I thought I must run through the throttle linkage to make sure all was running smooth, and we had full shut and open on the throttle plates. Whilst playing with the cable adjustment I noticed that at WOT there was a lot of strain on the cable, and discovered that the throttle peddle has a long forgotten (by me) adjuster/stop bolt to take the strain off the cable at WOT. The locking nut on the bolt had worked loose allowing the bolt to vibrate inwards a few turns, so all the strain when I stamp very hard on the peddle coming out of turns at events was being taken by the cable, the probable reason why the original snapped the other week.

Alan

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I've had the opposite to a broken throttle cable, throttle stuck wide open, twice!   So I've got return springs on all three throttle bodies, and there's a lot of tension at WOT.  

So I've just fitted dual cables.   Looks OK, still have to test drive! 

IMG_20180514_165813.jpg

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Funny the circles we create, I also had very heavy extra return springs working on the safety first principal, when Nick and I swapped Vitesse's at CC last year, he commented how hard it was to press the peddle on my car, whilst I found it strange using NIck's with what felt like zero pressure.  Looking at my data logs where I have recorded TPS for a couple of years I could see that a number of times where I thought and should have been at WOT I was actually backed off a bit, which I concluded was from over strong return springs making it easy for my foot to relax a bit. So I actually softened off the auxiliary springs, which from the data logs seems to have worked, however I think the upshot was that instead of the return springs relieving some of the load on the throttle linkage and hence the cable, I was able to exert maximum load on the cable and without a carefully adjusted peddle stop overloaded it!  

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Meanwhile, back at the Neanderthal end of the forum, I forgot to mention that the cotter pin holding the securing screw on the top end of the link had been inserted in such a way as to foul the carburettor connecting rod at half throttle opening.  Simple, obvious stuff.

I took the car on a brief outing yesterday evening and discovered that there is a whole world of unexplored throttle travel (mainly because the pedal is now so damned light that I can barely feel the thing under my hoof) and the combination of the skimmed head, bigger valves, lairy cam, bespoke dissy and shedded emission crap was all there waiting to be discovered.  In spadefuls.

Now it suddenly feels worth finding a rolling road.  Just so I know...

Paul

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Image result for Neanderthal in modern dress

We are all Neanderthals now, Paul!

If this guy walked past you in the street, you might look, but you wouldn't think him that different!

Anyway, you and I represent here two of the other Great Ape species, so it's not for us to say!

John

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I prefer to be photographed on my left side, John!

My avatar was a toss up between the wistful/uncomfortable chimp you see at left and the image below.  Most of the time, I find myself to be one or the other...

Paul

apes.jpg.9682553e04b703f9e4e5c0636b23f490.jpg

Edited by PaulAA

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