Section : Carburettors

Carburettor overhaul 

Posted By : Mark Telkman, 21-Jan-2005, 03:53pm

As some of you are no doubt aware, I bought a second hand pair of HS4s to overhaul and replace my exisiting single HS4. It's not surprising the previous owner had taken them off - the inlet manifold water pipe was completely blocked, took a couple of hours of stabbing at it to clear everything out. The rubber seal between the jet and one float bowl had got itself completely jammed, letting nothing through, which I eventually had to burn out (quite a quick job, being soaked with petrol). The other jet was completely stuck fast in the base of the carb.

After a day dismantling them to find my way around them and to order the right bits for creating the linkages and overhauling etc, I then spent a day sorting the inlet manifold, spray painting etc and a day going over the carbs. Nothing amazingly exciting, but I was quite proud of myself for managing to take them apart and put them back together with no unexpected bits left over - this is about as involved with the mechanics of my Spitifire as I've had the chance to get so far!

I probably could have done a slightly better job on the cleaning of the outside, but as long as they work, who cares what the look like? I'm still waiting on some bits from Canleys and Moss, but hopefully once here I should be able to get them on and see how they go - I'll let you know

• Carburettor overhaul 

  Posted By : James Carruthers, 21-Jan-2005, 04:04pm

  Mark - looks excellent - though those dashpots should really be shiney!
  
  I wouldnt use those air filters if I were you... they're not that brilliant at all... they just make a hiss and don't last long - I reckon the standard paper ones work best - and its quieter!
  
  

  • Carburettor overhaul 

    Posted By : Mark Telkman, 21-Jan-2005, 04:11pm

    I may well polish them up with something when I get the chance
    
    I've not got any of the airfilter box/assembly, so these are nice and cheap for the time being to save buying all that, when I'll only replace it after a while with something decent.

    • Carburettor overhaul 

      Posted By : James Carruthers, 21-Jan-2005, 04:15pm

      I have a spare airfilter box etc etc - or else take a look at Stoneleigh (if you're going) usually lots about...
      
      

      • Carburettor overhaul 

        Posted By : Mark Telkman, 21-Jan-2005, 04:30pm

        Stoneleigh would be a little far for me - cheers for the offer, but I might as well stick with these for the time being, unless they cause any problems - hopefully I'll have got enough to get a decent exhaust and some K&N's before long

        • Carburettor overhaul 

          Posted By : Ian Palmerino, 21-Jan-2005, 07:06pm

          Mark
          i have the airfilter box, in chrome, not sure if it will fit tho (came with a load of parts i picked up).
          i know it doent fit my stromberg's so i guess it must be for su's. its yours if you want to pay postage, you could measure the bolt holes and let me know and ill check if you want.
          
          where in hants are you, im in sussex and go to soton once every couple of months to visit family so could poss drop it in if your that way.
          
          Ian

    • Carburettor overhaul 

      Posted By : William Davies, 21-Jan-2005, 05:57pm

      Hi Mark,
      Rememebr that the flow through the airfilters will have a bearing on the needles you need in the carbs. Change the filter type and you could end up having to spend on new needles, so the nice and cheap filter may end up costing more than you think.
      Just sold an airbox on ebay for a fiver, the buyer paid more on postage than for the part itself! The original type filters are the best all-round solution, K&Ns are great at making, the only performance advantage seems to be at maximum revs,
      Cheers,
      Bill.
      

      • Carburettor overhaul 

        Posted By : Mark Telkman, 21-Jan-2005, 06:59pm

        For the moment, I'll stick with the standard ABTs unless they cause me any serious headaches. For the time being I'm just trying to make the car as decent a daily driver as I can. In the long run, I'm hoping to properly overhaul the brakes and suspension before heading for a few upgrades for engine performance around the same time - ideally I'd like to find a rolling road to tune it on, but I guess I can always play about with a few needles at home and see what works best if I can't afford it. In the really long term, I'd love to take it racing, but money rather gets in the way of that one for the time being...

• Carburettor overhaul 

  Posted By : Mark Telkman, 21-Jan-2005, 04:06pm

  Heh, just after I write that, a delivery turns up from Moss - one 30p bolt that they missed off the first order.... Shipping charge - &163;9!
  
  I'm still waiting for a couple more tiny parts that were out of stock - I think I'll cancel them and go elsewhere to save myself obscene shipping charges for those too - could have sent it in the same amount of time with a single first class stamp

  • Carburettor overhaul 

    Posted By : James Carruthers, 21-Jan-2005, 04:11pm

    Canley send you stuff free when its out of stock... at least I never get charged...
    
    

  • Carburettor overhaul 

    Posted By : Philip Wright, 22-Jan-2005, 04:59pm

    Mark,
    
    Any bits you need, give Andrew Turner a ring - what he doesnt know about carbs really isn't worth knowing! He'll be at the Stoneleigh show on 6th Feb, failing that his nunber is -01572 767665.
    
    Carbs look good! - hope you're bringing your car to Stafford this year? - I certainly will! Any more 'stoodents' or ex stoodents up for a few beers?
    
    Phil

    • Carburettor overhaul 

      Posted By : Mark Telkman, 22-Jan-2005, 10:03pm

      Assuming everything goes to plan, I should have everything I need to get them going for the time being - as far as Stafford goes, it's a bit far for me this time around... the SEM seems more likely