MK3 Posted August 8, 2014 Share Posted August 8, 2014 My Mk3 1300 is running very rich, I have the jet adjusting nut all the way to the top and it's still way too rich.I checked both float levels and they are miles out, too high, so they need adjusting.The floats are the Plastic variety, so the needle valve casing needs a spacer washer under it to give the 3.12mm correct float height. I checked both carbs and there are no spacers under either.I have browsed Burlen and a couple of Triumph suppliers but all I can see are complete gasket or rebuild "kits"Any ideas what size of washer I need to give the correct float setting and where I can get 2 from ?thanks Quote Link to comment Share on other sites More sharing options...
Velocita Rosso Posted August 8, 2014 Share Posted August 8, 2014 The float has nothing to do with running too richThe problem will lay in either the jets being too worn (if the jet is at its highest point) or the needlesFit new jets first and take it from there.As the needle lifts and lowers there can be considerable wear on the jetsThe float chamber level has no bearing on the amount of fuel being sucked in are you sure the choke is not sticking on? Quote Link to comment Share on other sites More sharing options...
junkuser Posted August 8, 2014 Share Posted August 8, 2014 Would be worth getting the float level correct first.You could cut washers from fibre type gasket material and just experiment to get correct setting.Soft aluminium would be suitable, just more difficult to work with and you would be lucky to get the correct thickness. Quote Link to comment Share on other sites More sharing options...
MK3 Posted August 9, 2014 Author Share Posted August 9, 2014 I suspected worn jets and/or needles to begin with but thought I'd check the float levels first and eliminate them as I saw a pool of fuel across the bridge. I have made some packing washers out of gasket material so now the float levels are correct.I suspect it is the jets that are worn, I swapped the pistons & needles from a spare set of HS2's and it's still running rich.So that only leaves the jets - do the jets and needles wear together or are the needles hardened ?The choke is adjusted correctly and not sticking on. Quote Link to comment Share on other sites More sharing options...
Velocita Rosso Posted August 9, 2014 Share Posted August 9, 2014 The needles and jets are made of brass(for obvious reason) however there is a difference (hard/soft) in brass and one could wear more than the otherIf needles have been profiled ,previously, and they have not been smoothed off with emery then the needles can act as files and make the jets more openHowever on reflection ...if the jets are at the top of the chamber eg flush with base ,its possible, if still standard, you might find the needles are wrong....may have been changed by poI would invest in new jets first and maybe a pair of AAQ needles....not a lot of pennies http://burlen.co.uk/ Quote Link to comment Share on other sites More sharing options...
MK3 Posted August 9, 2014 Author Share Posted August 9, 2014 OK, thanks, from memory I think it has BO needles in at present, not knowing the history of the car I'm not sure if these are the right ones or if a PO has changed to them or even if the engine has been modified at all .. - it's a 1970 MK3 1300 with 4 branch manifold and a very loud 1 into 2 straight through ss exhaust with twin silencers at the back which I think could do with a single central box "resonator ?" in the middle to tone it down a bit Quote Link to comment Share on other sites More sharing options...
junkuser Posted August 10, 2014 Share Posted August 10, 2014 "I saw a pool of fuel across the bridge"Fuel level this high will definitely cause rich running at idle. Quote Link to comment Share on other sites More sharing options...
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