Reply To: My Special’s running problems!

Welcome to the Allard Owners Club. Forums Technical Talk My Special’s running problems! Reply To: My Special’s running problems!

Dave LoveysDave Loveys

    <p style=”text-align: center;”>Hello Tim. Before you spend time and money on the fuel tank removal and other various remedies check your fuel line back from the carburettor.  If the bore of the pipe is not much less than the carburettor iintake right back to the tank then that should be fine. On both my Allards the fuel pipe comes out at the top of the tank via a special fitting held in with I think 6 set screws holding it in. If you remove this fitting you will find,  if original 2 pipes going down into the tank. One pipe should be longer than the other by about  an inch. The bore of these pipes is about 1/8th of an inch if my memory serves me correctly.  The longer pipe used to be the reserve which was operated by the reserve switch on the dash via a solenoid in the pick up fitting or close to the tank fitting. My P1  had the remains of it present but we took the disintegrated pieces out and connected that line to the electric pusher pump, an ordinary SU pusher pump as found on Healey 3000, and Austin Westminster 3.litre. This was all a long time ago but if I remember correctly the 2 pipes joined into the main fuel line which fed into the mechanical engine operated pump and on into the carburettor.  This worked well on my P1  for many years.  When Roger and I did the Monte Carlo Classic Rally in 2012 we were plagued by engine misfiring problems all the way there and back, and indeed for 12 months afterwards. We got home from Monte on a various amount of cylinders, rarely 8  and suspecting fuel problems went through the lines and into the tank. We did find that the drop pipe into the fuel tank had a hole on it about 2 inches from the bottom, but couldn’t find anything else. Fortunately the reserve drop pipe was OK so the car would run on the electric pump when the fuel level went below the hole in the other pick up pipe. Anyway, in desperation to cure the car I went the electronic route and took the old points type distributor off the P1 and fitted the electronic distributor and leads from my perfectly running K1 onto the P1.  Since that day the P1  has never missed a beat. I bought a new electronic distributor set up for the K1.  Both cars have been fine ever since. For the record I run both cars on the Mechanical push rod operated pump all the time on the road and also when doing competion with the K1. It has been around Goodwood in about 3 seconds less than 2 minutes beating Joe Cleggs Jaguar 3.8 engined K2 by more than a second. Joe has since put a Caddillac back into his K2. The only time I have ever needed the electric pusher pump is to overcome fuel vapourisation.  For these reasons I am extremely doubtful you are starving of fuel due to insufficient bore size of the fuel line. I think it is possible you may have floating debris in your tank. This gets drawn by suction to the end of the pick up pipe, stops your fuel supply, then the engine. Once the engine stops and you switch off the fuel pump the suction ceases, and the turbulence of fuel in the tank frees the pick up pipe, and off you go again until the next time. My International tractor had this problem. When I drained the tank, the outlet is at the bottom and I had to use a piece of wire to get it to drain, I fitted a tube to my workshop vacuum cleaner and sucked the rubbish out of the tank through the filler. I found the debris causing the problem was a piece of instant gasket, which of course  was quite happily floating about in the fuel. Problem solved. If you are 100% sure about the distributor  and plugs and points    this where I would be looking now. One other simple thing to check. Make sure your carburettor gaskets are sealing. If air can get in anywhere except through the carburettor intake this will cause similar problems to fuel starvation. Easy to investigate, cheap and easy to fit new gaskets if uncertain. Dave. P S The previous owner was the naughty culprit who had sealed the fuel gauge Sender unit with instant gasket instead off cutting out a proper gasket. Mind you it had lasted well over 15 years before I had a problem.</p>