F1 Sport - more running problems

barney
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F1 Sport - more running problems

Post by barney »

Graham, Richard - Please help!I'm still having horrible problems with my F1 Sport.I traced the poor starting to a failed regulator/rectifier unit. That's now been replaced and the battery holds charge, and the starting is vastly improved.I still have the annoying poor slow running, where it feels like the bike is running on one cylinder. A blast of the throttle will fix it, but if it stalls when it's running on one, it's almost impossible to restart until bike has cooled and stood for 40-50mins.This week I had an even more serious issue. The bike cut out on a motorway run. I'd done about 60miles on the motorway at a steady 70mph with no problem at all. Suddenly I lost all power. I had a couple of backfires, and costed to a complete stop. All the visible electrics on the bike seem to be working, but it would not fire up.I was recovered home, and tried the bike again at home. Still wouldn't fire.Now 2 days later I've been out to the bike strip the tank and seat and test the HT circuit. To my amazement, it's fired up. Huge, and I mean, huge clouds of smoke, but it's running fine.I'm thinking all of my problems must be linked to an HT ECU problem.I think I lost spark on the motorway - I suspect the backfires where caused by unburnt fuel in the hot exhaust.I also think the clouds and clouds of smoke are caused by unburnt oil in the exhaust/cylinders.Am I right? or is there something else that could be giving these problems?Could it be my coils are failing? They get exposed to a huge amount of heat. Is there a way to test the coils separately from the ECU?I have a NML ECU on my bike - unit no2. Is it possible I can test this at all?Many thanks in advance.Barney.
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Interpol2471
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Re: F1 Sport - more running problems

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barney wrote:I still have the annoying poor slow running, where it feels like the bike is running on one cylinder. A blast of the throttle will fix it, but if it stalls when it's running on one, it's almost impossible to restart until bike has cooled and stood for 40-50mins.
Hi Barney I had a very similar issue to this on my IP2 and found that my carbs were in a real state, I stripped and cleaned them replacing the choke 'o' rings and then re-set the mixtures. Once balanced the bike changed dramatically with better starting and idling with cleaner balanced running. I know you have diferent carbs to the IP2 but it may well be worth giving them a clean and checking the mixture / plug colours. Good luck, or you may think of selling the bike cheap to me to clear you workshop Very Happy
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Richard Negus
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Re: F1 Sport - more running problems

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Barney,Firstly, the carbs are exactly the same on the Sport as the Commander and IP2, and suffer the same problems that Paul experienced with his.Before checking anything else, I would overhaul the carbs, replacing the choke o-rings, setting the jet heights with a depth gauge, and using SAE40 in the dashpots.Check the needles are clean (I've seen old-fuel residue collected on needles which must affect the metering) and check the float needles are in good condition; Burlen do a viton-tipped float needle/seat kit (VZX1101, I think) as an alternate to the standard nylon needle. Includes some gaskets that don't fit the HIF4.When refitting the carbs, be sure that the idle pipes (which run alongside the main induction pipes, are fully engaged with the castings at each end. An air leak there does cause MAJOR crap running.When you've done all that, and no improvement, the next might be to check the ignition unit either by borrowing another, or take/send it to Rugeley where there is a test rig.If that is ok, then poor hot re-starting may indicate loss of compression and an engine strip for inspection.First things first though !R.
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Re: F1 Sport - more running problems

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Thanks both for the replies. I can understand how dirty or poorly set up carbs could give poor slow running and tick over. But would this cause the bike to stop completely from motorway speeds?Barney.
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Richard Negus
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Re: F1 Sport - more running problems

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Barney,The sudden stop at speed does sound more like a significant electrical fault.If you're sure the replacement regulator is correct, then check some of the following 'usual suspects'.. look at the fuse box/wiring loom connections for signs of overheating, particularly the main 30A one.. look at the main fuse - is the green plastic starting to melt or are the terminal blades burned.. check the AC connections at the generator and regulator for signs of overheating, indicating high resistance at the terminals.. is the side stand cut-out relay secure.Your bike was rebuilt with mostly new switchgear about five years ago so those are unlikely to be faulty.Check the fuel pump will work continuously by directing the flow back into the filler neck rather than to the carbs. R.
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Interpol2471
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Re: F1 Sport - more running problems

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Richard Negus wrote:Firstly, the carbs are exactly the same on the Sport as the Commander and IP2, and suffer the same problems that Paul experienced with his.
There was me guessing you had the later Mikuni's red face Richard puts me to rights again cry Barney as Richard says I had terrible running issues until I sorted the air by pass pipes and the carbs, and I also had a one off issue when the bike just stopped and that was also due to the side stand switch.
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barney
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Re: F1 Sport - more running problems

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Hi again both. So I have started to strip the bike this morning. Note the bike started first push this am!Coils seem ok. I even primary windings about 8 ohms primary to secondry about 7k. I even baked these at 80 degrees for an hour to see if temperature effected them. It didn't. I've removed the black air box spacer to check the inlet tract. Nothing. Also the carbs are as clean as a wistle. The connector from the alternator is fine too. The only thing I can find is the main fuse has been effected by heat at some point. The fuse is still correct but the plastic body of the fuse has split. I'll replace this as a matter of course but does it give any clues?Richard - the gasket between the airbox and the block split when I removed it. I can repair it, but don't know how critical it is. If it is critical can I get a new one from anywhere? If not what should I make o e out of?Many thanks,Barney. Barney.
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Richard Negus
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Re: F1 Sport - more running problems

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[quote="barney"]I've removed the black air box spacer to check the inlet tract. Nothing. Also the carbs are as clean as a wistle. What black spacer ? Carbs may be clean, but do replace the choke o-ring while you're in there. Richard - the gasket between the airbox and the block split when I removed it. I can repair it, but don't know how critical it is. If it is critical can I get a new one from anywhere? If not what should I make o e out of?Original gasket is asbestos-based & nla ; you can use silicone sealant (rtv) as an alternate, but let it cure for 30 minutes or so before fitting the airbox.R.
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Re: F1 Sport - more running problems

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It seems todays work hasn't fixed it after all! After a good 20 mile ride with perfect running I started to get the missfire problem again. The bike stalled and after an hour of trying to restart it I've given up and called Carole Nash recovery for the second time in a week!Some new observations this tme thou'1 the file pump was running constantly when the bike stalled. I could stop it running by pinchng the supply to the carbs, but as soon as I let go the pump started clicking again. This feels like a sticking float value to me is that possible?2 I got the pump to stop running by shaking the bike back and forth on the shocks. I figures this would loosen the float value. It seems to have worked as the pump only comes on saradically. 3 there's a very strong smell of petrol. So Im starting to think it must be carb related? Richard does this sounds like a float value chocke oring problem the more I discover?Many thanksBarney. Stuck waiting for a recovery truck!
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Interpol2471
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Re: F1 Sport - more running problems

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The choke o ring would only cause rich running as it allows fuel past the metering hole assy into the airflow of the main venturi. This sounds more like a sticking float or needle allowing fuel to flow constantly and flood the engine. The o rings are easy to check after removing the carbs, just remove the bottom screw of the enrichening mech and then turn it so you can see the second screw, undo it and pull the brass assy out of the carb body and you will see the o ring on the assy. The needle valve and float are enclosed in the bottom of the carb under the four screws held bottom plate. Good luck
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Richard Negus
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Re: F1 Sport - more running problems

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Barney,If the pump ticks continuously on a Sport, then either you're out of fuel, the feed from tank to pump is blocked and the pump can't suck fuel, or the carb is flooding and filling the engine with fuel.You can check the second and third by squeezing the pipe between pump and carbs to see if it then stops ; if the pump stops, then it's flooding ; if it doesn't, then there's a supply problem.You say it stopped when you squeezed the pipe, therefore it's flooding and carb overhaul time. It may be a piece of debris in the fuel passages so a good blow out is needed plus replace the needles and seats ; use the viton-tipped ones for preference.For other readers, note that the older F1 fuel feed system is completely different in operation !R.
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Re: F1 Sport - more running problems

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Thanks Richard.I definitely think it's a carb problem now. As you say, the pump stops running when I squeeze the line to the carb, so I think it has to be a needle/dirt problem.Please could you tell me what the spec/model number of the carbs are? I'm guessing they are 1 1/4 HIF Type 4?Many thanks,Barney.
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Interpol2471
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Re: F1 Sport - more running problems

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I am not Richard and never will be but my age is catching up lol red face but the carbs are SU HIF4 1 1/2" diameter SU numbers FZX 133L and FZX133R. The parts required can be bought from Burlens Fuels in Salisbury who are SU specialists or Norton Motors may still have the overhaul kits part number 55-0715.I have recently fitted viton tip needles also and as said above are in the bottom of the carb, also change the choke o ring while you are here as it will be perished and it is easy to do at the time. Richard also suggested to me that this is the best time to check the jet height with a vernier but remember this is a start position if you move it and it will most probably require fine tuning after that. This is easy and the same as any other twin just adjust both sides for the best running/idle spot and test. Hope this helps and sorry for keep having my say Richard but you know me wink
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Re: F1 Sport - more running problems

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Hello both,Here's this morning's instalment!I've stripped the bike. I must have had a serious float needle issue. The carb spacer/mounting box had about 250ml of fuel in it!! So it was obviously running a bit rich!!I've removed the carbs. I elected to remove these from the copper down pipe and leave the manifolds attached. It seemed easier to do this because of the restricted access around the carbs.I've removed the float chamber lids, floats, needle valves and needle seats from both carbs. There's no obvious sign of sticking in the float needle, and the needles are metal tipped rather than plastic.I've also removed the choke assembles. The o-rings both look in good condition.I haven't disturbed anything else on the carbs.So here's today's questions,1) When I reassemble the copper tubes into the manifolds, should I use any form of sealant?2) Given I haven't moved the main jet or needle do I need to re-adjust it? If so to what level and how do I do this?3) Is there an easy way to check the float hight setting? and check the floats are working correctly before I re-assemble the bike?as always, thanks again in advance,Barney.
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Re: F1 Sport - more running problems

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From previous experience, Burlen don't recognise the SU numbers for Norton carburettors as they were very special ; Burlen don't / didn't recognise the FZX133 series.Neither NML nor Burlen have the spares kit in stock at present ; I had the last three smiley from Burlen on Friday & they said another 3 weeks to make up more kits ; Burlen will have all the individual parts though. NML have choke o-rings as a separate part as well as the gaskets for each end of the carb and the o-rings (55-0362) for idle pipes and idle adjuster.Burlen have VZX1101 viton needle/seat kits in stock.If Paul keeps giving us the benefit of his own hard-won experience, how am I ever going to be top-poster ? I'm not paranoid, it's just I think he's trying to keep me in my place. evil R.
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Re: F1 Sport - more running problems

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Thanks Richard - so if I just replace the o-rings in the manifolds i don't need to use any sealant?Barney.
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Re: F1 Sport - more running problems

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Just use vasoline as it aids assembly and saves any damage to the o rings and is of course petroleum based. Check the length of the idle pipes and make sure they seat fully in either end and are not too proud of the shoulders. AS Richard says change the needles for the ones he has part numbered for you (Boring Man Very Happy ) and check the floats are ok and not leaking.The manual for checking all carb setting is available for download from Startrights website. Remember this as you say may be fine and may only need a tweak to fine tune I found even 1/2 a turn made quite a difference to the bikes feel and idling.Richard dream on about being top poster wink mind you maybe you are the best poster cry
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Re: F1 Sport - more running problems

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Hi BarnieI had a similar problem on my F1 it would tick over for 5 minutes + then stop, sometimes it would not start for an hour or so but not all the time. Put a new ignition on no difference, put a brand new set of carbs on no difference, three months later total failure, once the start button was released, hay presto faulty ballast resistor. Fitted a new ballast resistor problem solved the bike ticks over and runs as good as everMy conclusion is, when stopping at traffic lights the heat was getting to the resistive element in side the ceramic case causing voltage to drop at the coils and the bike to cut out but it would restart. When I parked the bike I suspect the heat really got to it hence why it would not start for an hour or so.That’s my theory what causing my problems , but it took me two years to solve, drove me bonkers and I proberbly drove both Richard and Graham to distraction as well. The bonus is I can now remove F1 carbs strip and them in my sleep.Hope this is of useWayne
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Re: F1 Sport - more running problems

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I always carry a spare ballast resistor with me. If the engine will run with the starter button pressed the resistor has failed. Buy an early Ford Transit one from your local spares shop. Emergency get you home trick, join the feed & return wires together to remake the ignition circuit. I have no idea why the designers fitted them & neither do Boyers who told me they were not required in the ignition system. Richard, perhaps you can explain the logic. I know they brought the coil feed down to 6 volts to give a better spark. Maybe? Or is it just a throwback to the Commando days? On my Commander I mount it on the fairing bracket in the nose so I can change it quickly via the headlamp aperture. Derek.
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Re: F1 Sport - more running problems

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Dell Boy wrote: I have no idea why the designers fitted them & neither do Boyers who told me they were not required in the ignition system. Richard, perhaps you can explain the logic. Derek.
Hi Derek,Strange, since the Boyer system was introduced on the Classic and was developed by Ernie Bransden specifically for Norton. I presume Ernie has retired now ?The idea of the ballast resistor was to give a better spark for starting, when the ballast was by-passed with a direct feed from the starter solenoid to the coils (the orange wire). With the starter motor operating, battery voltage reduces to around 11 volts which isn't very good news for 12 volt coils - but good for 6 volt coils. During normal operation the ballast drops the voltage at the coils to around 9 volts.The original Lucas ballast is a PITA, causing more problems than anything else on the bikes. The resistance wire is only held by a crimped termination (under the ceramic filler) and very prone to corrosion. There is a modern replica which has the resistance wire pinched under an M5 bolt which may be more reliable.Bear in mind that idle speed of the Norton rotary is controlled as much by the ignition retard as the idle air adjuster. Full advance ignition timing is nominally 18 deg. BTDC with around 50 degrees of retard at 6-800 rpm. This means that, at idle, the spark occurs at 32 degrees AFTER TDC. The problem that Ernie tried to overcome was the reluctance of hot re-starting when the ignition system is at full retard and compression may be a little low due to thinning of oil around the rotor seals. Cold starting wasn't normally a problem as the ignition system was then at full advance and the oil more viscous.Only introduction of more modern digital systems allowed momentary full advance at cranking speed to urge a hot engine into life and then revert to full retard for normal idle speed.R.
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Re: F1 Sport - more running problems

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Thanks for all the follow on comments and just a quick note to update on the situation with my F1S.I've now got all the new o-rings and float needles. The only obvious problem I noted during the carb strip was the paper seal missing of one of the cold start mechanisms. The o-rings looked in good shape - but I have replaced both o-rings and fitted two new paper seals just to be sure. I've also fitted the new float needles. I'm sure these where the cause of all the problems. The fact the petrol pump kept running - but stopped when I squeezed the pipe, and the fact that the air-box space thing was half full of petrol, really makes me think I had serious flooding on one cylinder.The carbs are clean and ready to go back on the bike this w/e. I'll keep you posted.I just have to hope 'er in doors doesn't come up with some other chores for my attention this w/e!!Barney.
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Re: F1 Sport - more running problems

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Hello Barney, I would flood the chamber that has been washed out by leaking petrol with a lot of lubricating oil because it could be "dry" & if fired up could cause smearing. In fact do both,it wont do any harm & will aid starting though the smoke might upset your neighbours!!! Derek.
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Re: F1 Sport - more running problems

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Hello Richard, It was Ernie I spoke to but he could remember nothing of the design details. It was all to long ago. He did make the comment when I had to buy my first replacement unit about 15 years ago that they weren`t told it would be piggy backed onto the voltage regulator which cooked them. He made me up a sub harness to extend the wiring so i could mount it in the nose cone where it runs nice & cool & has never failed since moving it & performs very satisfactorily. Regards Derek.
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Re: F1 Sport - more running problems

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Hi Derek,We learned the same thing in Service !Commander ignition units were re-fitted to the l/h front side of the fuel tank with a short extension harness & F1's to the rear subframe with a long extension.In both models, most of them didn't give a problem however.R.
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Re: F1 Sport - more running problems

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Hello all,GOOD NEWS!!!I think (touch wood) we've solved all the problems. I had the bike out for a 120 mile run this morning, without a hiccup.I finished putting the carbs back on the bike yesterday - it started fine I just had to adjust the tickover. Interestingly it was ticking over so slowlyafter the rebuild it would just stall. I've set the mid temp tickover at just under 1k (using the bikes clock). I find the tickover increases very slightly with temp. If the bikes hot tickover will increase to about 1.2k.So I ran the bike this morning - did about 30miles in town. I was easily able to pootle along at 30 - 50 mph in high gears at 2 - 3k rpm. The bike still gets warm at slow speed, but I have NEVER been able to tick along at slow speed like this before. I finished the ride off with a 90mile blast on A roads, B roads and motorways. I stopped for fuel and the bike restarted FIRST push!! I was also able to tickover at round-abouts and traffic lights - another first!!!!So to recap here are the lists of faults I found,Regulator Rectifier - had died, this caused the battery to be over charged and boiled 2 batteries. This made the bike really hard to restart when it died!!Float Needles - I think these where the critical items. Given the amount of excess fuel in the spacer/airbox I think the bike must have been running massively rich, and I suspect the stalling and failure to restart was due to serious flooding.Choke O-ring - I'm not sure these where causing any fault - but they have been changed anyway.Thanks to everybody on this list for their help and advice and now I have a reliable bike I hope to meet some of you on a ride out soon!!!Thanks again,Barney.
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Re: F1 Sport - more running problems

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Congratulations !All you need now to complete the job is to get the hot idle speed down to around 600rpm (which is almost off the bottom end of the tacho scale).After starting from cold, and with the choke returned to the normal riding position, it should fast-idle at around 12-1400rpm. As the water temperature rises and the temperature switch closes, this should suddenly drop down to 6-800rpm.The idle air adjusters (not the twin-slot screws on the carbs) should be screwed in 1/4 turn at a time to bring the hot idle speed down. Final adjustments to get a smooth steady idle may require one screw to be turned in or out more than the other. Trial and error, I'm afraid.Getting a low idle speed will make entry into greasy roundabouts less of a buttock-clenching experience. Works for me, anyway.R.
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Re: F1 Sport - more running problems

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Hi Richard,I've got it running at about 1k on hot idle at the moment. (I notice it lifts slightly to about 1.1 - 1.2k if the bikes been in traffic and is getting up towards the red zone on the temp gauge.)To get the tick over to this level I adjusted the throttle cable tension at the twist grip. I did this because I couldn't find an adjusting screw on the carb. (I was looking for a screw to adjust as per a mini or a moggie thou's SU) Where are the air idle adjusters located? are they at the front of the engine near the butterfly valves?Barney.
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Re: F1 Sport - more running problems

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Hi Barney,Secret, if it tell you, I'll have to shoot you !They're on the outer sides of the carburettor outlet castings and you need a long flat blade screwdriver to reach them.Take off the side panels and the trim panels ('hockey sticks') and you'll find a hole about 12mm diameter drilled through the frame on each side; look down the holes (a torch helps) and you'll see the idle air adjuster screw (about 12mm diameter, anodised silver, single screwdriver slot). The holes may be hidden under a white decal.Firstly, make sure the throttle cable has some free play and the butterflies are completely closed.Turning it clockwise reduces the airflow, anticlockwise increases. As a guide, start with the end of the adjuster level with the face of the casting.This adjuster only works when the butterflies are completely closed and acts as an adjustable by-pass around each butterfly so it is essential that both are closed.I'm away for the rest of the week so will be unable to make another reply until Saturday at the earliest.R.
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Re: F1 Sport - more running problems

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Barney, "A picture's worth a thousand words"Look in my Gallery / Supreme Commanders.There's a close-up of the carb and idle adjuster on my Commander.Same carb & same adjuster on your Sport - but far less accessible for you.R.[img]C:\Documents%20and%20Settingsorton%20Mptors\My%20Documents\My%20Pictures\Idle%20air%20adjuster[/img]R.
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Re: F1 Sport - more running problems

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Hello Richard and all,So I now have the tick over fixed. It's difficult to say what the RPM actually is as the needle only just lifts of the rest on the tacho, but I guess around 600RPM. The actual adjustment was easy, but getting to the adjusters is a pain! However, several cups of tea and a long screw driver later we're off and away. So thanks again to all for all the help and support.As an aside - given the mantra it never rains but it pours, my 1967 MG Midget developed a curious missfire last week. Opening the bonnet revelled petrol pouring out of a float chamber. (It's a lot easier to see when the carbs are clearly visible!!).I've found out two useful things.1) The float needle assemble VZX1101 is widely used on MGBs, Midgets and we suspect Moggie1000, meaning any good classic car centre should have these in stock. My local one certainly did.2) According to the garage the needles have been redesigned to include the new rubber/teflon tip as modern petrol erodes the old tips. The guy at the garage reckons they virtually never changed a float needle until about 5 years ago - now he thinks it's one of their most common problems. I raise this as I guess this could be a problem for anybody with an SU'd Norton.Hope this is helpful.Barney.
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