In > , "Fred" > writes:
>This is fairly common problem. If the car sits for a day or more, the fuel
>in the carb bowl may evaporate, or if your fuel filter is not the type with
>a built-in check-valve, a certain amount of fuel simply drains back down
>into the fuel line. So when you go to start it, there is not enough fuel
>present at the carb until the mechanical fuel pump gets cranked enough times
>to bring the fuel back. Swapping in a good electric pump eliminates this
>trouble. But.... hmmm... just re-read your post... 10 whole seconds of
>cranking is too long in any case. It usually only takes maybe 3 or 4
>seconds of cranking max to fill a carb bowl. What is your starting
>procedure? With all my old GM Q-jet cars, I will first press the pedal down
>about 3 times, then crank the engine for no more than 3 seconds. If it does
>not start, press the pedal down another 3 times, then crank again for
>another 3 seconds. And repeat this process until it starts. (Never just
>crank it for a whole 10 seconds straight.) Even if the car hasn't been used
>in over a week, it usually takes only 3 of these cycles max to get it going.
>It is important to pump the pedal so the accelerator pump squirts fuel down
>into the intake. Hopefully your accelerator pump is working ok... when was
>the last time your carb was overhauled? Well, if the accel pump was shot
>you'd experience a hesitation when accelerating. You can test the accel
>pump (with engine off) by looking down into the carb (primaries), then flip
>the throttle wide open, you should see two streams of fuel squirt down the
>carb throat. If not, you either have no fuel in the bowl or the pump is
>shot. Is the engine running fine otherwise? No vacuum leaks, etc? But...
>back to the fuel filter... you did mention that you replaced it recently.
>I've seen later model filters with built-in "check valves" which are
>supposedly designed to keep fuel from draining out of the carb bowl. I am
>personally not sure if these little plastic check valves really work, but...
>did the filter you pull out have the check valve? Did the filter you put
>back in have the check valve? Maybe the check valve does make a difference.
>As far as fuel pressure (condition of fuel pump)... probably not the
>problem. If the pump was bad, you'd have starvation problems while driving,
>etc. As for renting a fuel pressure gauge, they are cheap enough to just
>buy at your local auto parts store. Often you can get a combo vacuum gauge
>/ fuel pump pressure gauge... good to have in your tool kit, probably less
>than $50. Remember that fuel volume is just as important if not more
>important than fuel pressure... you can do a fuel volume test without a
>pressure gauge. The procedure and specs are usually listed in most repair
>manuals, easy to do.
>
>------------------
>
>"daveo76" > wrote in message
. com...
>> My relatively stock, L48 '76 is getting more difficult to cold start.
>> I'm probably up to 10 seconds of total cranking time for most
>> overnight cold starts. It starts fine after sitting all day at work
>> and it also starts great hot. The choke appears to be working fine.
>> I've recently replaced the fuel filter, plugs, wires, cap, rotor, --
>> all the normal tune-up parts. While replacing the fuel filter I
>> cranked it for a sec. to clear the line and check flow. Fuel was
>> pumped out immediately, but do I need to check fuel pressure to rule
>> out the pump? Can you rent fuel pressure gages from an auto parts
>> store? Any thing else I should check?
>
>

Agree on the fuel as a first look. If that doesn't work, pull
a plug wire and make sure you've got a very strong spark
while cranking. If there's any doubt, have the module in the
HEI checked (parts counter can do this) or just replace it
outright. I had starting issues with a '79 350 and a new module
fixed it. Old module was working fine at 12-14 volts but had
problems at low cranking voltages. Make sure any replacement
module is for early HEI and not the later EST or ECM ignition
systems. (IIRC this is identified by color code--haven't checked
the book but I think that the modules for ECM engines have different
number of connections.)

On your way past the rotor and down to the module, check for
red oxide (from the advance mechanicals) and clean that out. If
you decide to pull the distributor and don't have a timing light,
accurately mark things to restore ignition timing. Check for a clean
helix that carries oil up the distributor shaft to the bearing. After
a few years, helix gets dirty, bearing doesn't get oil...etc.

Hope this helps.... "Mike"
-- mikeellison3xxxatzzzyahoo.com --