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Re: Cold start probs and Travelling...

To: "Dan Neff @SMTP@Exchange" <neffster@mail.bemail.com>,
Subject: Re: Cold start probs and Travelling...
From: "Richard B. Chianese" <Richard.B.Chianese@swpc.siemens.com>
Date: Thu, 19 Aug 1999 13:35:32 -0400
"Dan Neff @SMTP@Exchange" wrote:

>    Seems like it's gotta be ignition. A roadster buddy thought there
> was some 'trick' to the Roadsters that added a little extra
> spark/voltage on cold starting, but he didn't understand the
> electronics. The thought makes sense, but i don't know what to
> pursue. I replaced the coil last Spring with a Pep Boyz number. It
> didn't have all the components to go with it (condenser thingy, the
> ceramic-with-wire-coil-inside didn't have the correct bracket, so i
> didn't install it, etc.). I had the steering column off to replace
> tach cable awhile back, but would've thought any ignition switch
> mis-connections wouldn't be so subtle.
> Any idea's? thanks..


Dan,

If the coil comes with an external resistor, the
"ceramic-with-wire-coil-inside," then it needs to be connected through
the resistor to survive.  Later model roadsters have the ignition set up
so that the coil sees full voltage on start and reduced voltage while
running.  The coil develops a lot of heat when you start the engine, but
because you are beginning with cold parts, the temperature does not get
too high.  The Pep Boys coil has probably overheated (hotter during
summer than during spring) and developed internal shorts or, worse yet,
breaks in the high voltage secondary side.  The coil can be tested by a
well equipped (ask if they have a Sun distributor tester) and competent
garage to let you know if it is still working properly.

The other possibility is that the ignition starting circuit is not
working correctly and you are getting zero voltage to the coil while
cranking.  In that situation, the engine only starts by chance when you
switch from start to run on the column switch and the running circuit
switches in.  The running circuit lucks out by catching one of the
cylinders near top dead center and successfully spins the engine.

You should be able to at least check continuity on the coil primary and
secondary side with a VOM.  Open is bad.  Not open may still be bad.

You could also check the voltage at the coil by pulling the wire which
comes from the dashboard off the coil and checking the voltage while the
key is in the run position and when it is in the start position.  You
should get near 12 volts in both situations.  Make sure the circuit
through the coil is not connected; the points switch the coil to
ground.  The voltage will bounce all over the place if the points and
coil are still in the circuit.

Good luck and be careful.

Rick Chianese
SRL311-14035

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