For you experts, where do I go from here.
The Car and Equipment:
70 Midget 1275 with HS2 and standard ignition. It does have Grose Jets
in the carbs (PO) and was supplied originally with the spring loaded Jet
Needle which it still has although they may have been replaced, there is
a old set in the spare parts box. The fuel pump is not SU, it simply
says "Auto Pump, Made in N.Z." but it fits and looks like it is doing
it's job. Compression is 180 psi in all cylinders and the engine
appears to be in good general condition. The air injection has been
removed and the plugs put in the head, crankcase suction is through the
"Y" pipe to the carbs and the Gulp Valve tap on the intake is plugged.
The problem:
The car starts and runs smooth at idle, however when I "blip" the
throtle it "sputters" and sometimes wants to backfire through the carbs.
When it is allowed to warm up to normal (170 Deg Water temp) it runs
much better. Still, in low gear (under load) it "coughs" before it
goes. Once at speed it runs fine and pulls strong in the higher gears
and at higher RPM.
What I have done:
Clean and adjust the carbs, checked that there is a supply of fuel to
the bowls and that the floats are not leaking. The carb adjustments
were made per Roger Garnetts instructions, including the beer, and again
with the info in the Haynes manual, then again with Garnetts way but
with two more beers. The choke is working and fully off when the
problems occurs. I have checked all other things such as valves,
timing, plugs etc. The carb damper has had 20W50, Marvel, and 10W30 all
seem about the same.
I now suspect the "off brand" fuel pump, should I pop for the SU or keep
looking for something else? What about float level with the Grose Jets,
I don't have instructions to go by. I also question the vacuum and
mechanical advance on the distributor, should I see the timing mark
change position when I put the vacuum hose back on following timing
adjustment? I don't see any noticable vacuum advance at idle, what
should the vacuum be out of the carb line? I can advance the timing with
the vacuum pump at about 15 to 20 Hg.
And my Spell Checker just expired!
Thanks for taking the time to offer suggestions, the beer is on me when
you come to Nashville.
Mark
70 Midget (had it 6 weeks tomorrow)
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