[Healeys] #174 has a running problem

[Michael Salter]

I have done the following;

STEPS TAKEN TO FIND RUNNING PROBLEM

This car has an original cap, original wires, original NA8 spark plugs,
original black coil, original fuel pump. I am determined not to change any
of these original parts unless I can confirm definitely that that item is
the source of the problems…it a concours issue!!

After many short trips 10 – 15 miles etc... the engine started to run very
badly after 35 odd miles of a longer test drive on a warm but not hot day
after travelling over a few hundred meters of rough road under construction
eventually stopping completely as I tried to climb a hill. Sounded to be
running on 2 cylinders at times. Backfiring through exhaust… no throttle
response.

Cranked but would not start..Appeared to have spark at the coil wire..

Affer cooling started out again…after 20 odd miles stopped with the same
symptoms… pulling choke seemed to make no difference.

Could not hear fuel  pump ticking but had fuel pressure at the front
carb……good spark at coil wire…spark at plugs looked thin …Changed the
condenser and the rotor and it started reluctantly and ran well for about
15 miles then stopped again….same symptoms….changed rotor…ran for 2 miles
same symptoms…

Found “3 cut” washers under the carb float chamber struts which I think
could be sealing off the vent slots for the float chambers…

Next day, today, I headed out for another extended drive and the car ran
perfectly on a similar day for 36 miles then repeated the problem after 36
miles and I just managed to nurse it home another 11 miles….it actually
died as I approached our driveway and I coasted in with the ignition turned
off.  Nothing would make it start.

Tested the coil 4.6 ohms with no short to ground. Took off the float
chamber lids and both were full to the correct level. The engine cranked
but would just not start..

After checking everything I could think of I believe that I have found the
problem but I don’t have time to do another 36 mile test before loading the
car to take to Enclave…

What do you think I found?

Michael..

-- 
*If you can't fix it with a hammer, you've got an electrical problem.*
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