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cliff.b

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Posts posted by cliff.b

  1. Hmm, I have just read that the 76 to 79 Spits had FZX1122 carbs and apart from any other differences these were fitted with ADN needles which appear to be leaner across the rev range than ABT's.

    ADN is grey line

    Screenshot_20230922-2138212.thumb.png.46f8598c5c3b89220d9e9ca9cdafc9ed.png

    I have always found that if I set the mixture at home it is always much weaker if I stop in a layby and check the plugs during a run. Guess this might explain why 🤔

  2. I'm considering refurbishing these carbs, maybe over the winter, but looking at parts I see there were  various carbs fitted to the 1500 Spit and even 2 different types of waxstat jet are available. Does anyone know what the differences are?

  3. In answer to all the above, I did some work on the linkages and refitted the jet so, by eye, the top of the jet was roughly the same height as the front carb. Adjusted further after a quick check with Colourtune then off for a road test which went well, to start with. I stopped & checked the plugs and rear ones were a bit weak, so lowered jet one flat. After this, the tickover was perfect and goes well with foot down, but running rough at slower speeds. Once again, pulling the choke out solved it do progressively richened the mixture and it got better, but not perfect.

    Now jet half a turn lower than the setting I started with and barely any difference to plug colour. I will work through all suggested here.

  4. Hmm, took both jets out and the rear one does appear to be a couple of mm longer. Might be due to the waxstat "bodge" but the jets are solid in the carrier with no discernable movement. So how did this problem suddenly come about.? 

    While looking at this I found the choke operating linkages are a bit sticky and I'm wondering if that jet has been stuck too low for ages and when I got the car running I adjusted around it. So if it suddenly freed up the jet would be too high and almost cut the fuel supply off to that carb at small throttle openings.

    Not sure if that is plausible but best I can come up with at the moment.

  5. Spitfire been running really well for ages but today very rough, won't tick over and feels like misfiring until throttle opened wider & revs rise. All ok if choke pulled out a bit. Found tickover no worse if plug leads 3 or 4 removed so assume rear carb problem. After further investigation I noticed the jet on that carb is protruding 2 or 3 mm and obviously, operating the choke cures this. This explains the problem and winding it down several turns gets the car running ok but now externally, everything is considerably lower than the other carb. Struggling to work out what has happened 😟

    IMG_20230921_154041_916.thumb.jpg.db35e9b80db567edc5865fe6a47177f1.jpg

  6. 1 hour ago, johny said:

    There is a theory that more danger does increase driver carefulness and I believe experiments have been carried out to test this by removing roads signs and traffic lights. I certainly treat my Vitesse with a lot of respect when driving it after having put the first one on its roof...

    Back in 1978 I put my first Spitfire, a Mk3, nose down into a roadside ditch and apparently went flying a considerable distance out of the open roof and ended up in a ploughed field. I say apparently because I don't remember it myself but there were witnesses.

    I'm in no hurry to repeat this.

    • Sad 1
  7. 4 minutes ago, johny said:

    Well the clamp plate (the grub screw goes into this) bolts must be tightened first with the grub screw completely slackened. Check the steering play and it should be minimal then tighten the grubscrew and finally lock it with the nut....

    Ok, yes, that makes sense. The bolts were right but so was the grub screw at that point do I will check again. Incidentally, I have just tested and the steering feels more precise then before so although I wasn't aware of an issue it may have been a bit loose for some time.

    Anyway, thanks for the help 👍

  8. I had about an inch play at the steering wheel rim but steered as normal when that was taken up. Wasn't like this a few days ago when I last drove her. Stopped and could see lower steering column not moving until flack taken up. Found locknut on safety clamp loose so tightened & play reduced but still there. At home tightened the grub screw and locknut and play now gone. Do you think this might be hiding another issue then?

  9. 11 hours ago, Colin Lindsay said:

    Am I correct if I remember that some of the other Triumphs were 'tweaked' slightly... too early in the morning here for proper brain function and not able to check properly... but they were given enhanced performance for journalists whilst being claimed to be production standard?

    As was the E-type, allegedly lol. Some say the car that was famously tested at 150mph may not have had a completely standard engine 🤔

  10. Unfortunately he was a bit short on technical details and obviously a marketing man but well aware of the issues that the motoring press had raised for the earlier cars.

    Anyway, it added interest to a very pleasant lunchtime with an old friend who also brought his classic along and enhanced by a couple of those other Spitfires flying overhead on a perfect sunny day. Things don't get much better than this 👍

    IMG_20230810_125225_145.thumb.jpg.72d52d210fe85311145ee3380f8c29ff.jpg

  11. Just arrived in a pub at Duxford to meet a friend for lunch and while waiting in the car park, an old chap came over and said he organised one of the press launches for the MK3 Spitfire. Claims they fitted them with rear suspension off a Vitesse so the motoring press wouldn't do the sort of things they did with the earlier cars.

  12. As I have just said on another thread, I will shortly be doing my re-torque and as advised, was planning on doing this with the engine warm. But this seems to be yet another of those things where there is a difference in opinion.

     

    So just wondered if anyone has anything definitive that clarifies this or if not, any compelling reasoning one way or the other?

     

    I presume if warm the studs would expand, thereby lowering the clamping pressure, but wouldn't the specified torque take account of this? 

  13. 22 minutes ago, PeteH said:

    The Theory behind backing off and tightening Nuts/Bolts, when re-torqueing. Is based on the possibilty of the nut having possibly slightly seized, the backing off, "ensures" the thread is as free as possible, and less chance of an error.

    Pete

    Ah, I missed this post. Makes sense.

  14. 9 minutes ago, Kevin Atkins said:

    I think Pete's explanation a couple of replies above makes sense, I can't remember whether the reasoning was mentioned in the video, and all cars are different I guess (especially Citroens 😜 )

    Here's a link to said video -

     

    Thanks. See he is doing it with the engine cold.

  15. 7 minutes ago, Kevin Atkins said:

    I think my mistake was that I loosened all the head nuts, rather than just doing one by one.. so whatever you do, don't do that! Do it one at a time - I've just watched a YouTube video of a chap doing exactly what you're about to do on a Citroen DS following a recent HG change, and he went through each nut in turn in the correct tightening order, backed off a quarter turn with a breaker bar, then re-torqued, and moved on to the next

    Did he explain why he backed them off first?

  16. 1 hour ago, johny said:

    Just for reference I dont think I would have released any head nuts but just tightened them up more to the correct higher figure following the pattern indicated in the manual. This is basically a head retorque that is recommended when a few miles have been done after a gasket change...

    Interested that you suggest not loosening nuts during a head re-torque. I'm almost at the mileage for doing mine after my recent head gasket replacement and most advice seemed to be to warm the engine, slightly loosen each nut then re-torque before moving on to the next one. Not sure what the reason for the loosening was though.

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