datsun-roadsters
[Top] [All Lists]

Missing on no. 3 - SOLVED!

To: datsun-roadsters@autox.team.net
Subject: Missing on no. 3 - SOLVED!
From: "Stephen McCartney" <sgam@hotmail.com>
Date: Thu, 03 May 2001 01:39:20 -0000
Hey guys, I'm a happy roadster owner!

For those of you who came in late:

Ladybird has been suffering a problem with no.3 missing.  The plug was 
getting all blackened, it would blow smoke, and generally be a real pain 
(especially as the EPA are advertising a blitz on smoking cars...)
Thing was, it was worse on hot & humid days, and worse in stop-start traffic 
(once on open road, it'd run pretty well, most of the time).
The usual suspects were investigated:

Plugs or leads?  Nope, swap 'em around, put in new ones, same problem.

Stem seals?  nope, fine.  Besides, compression was even across all 4.

Ignition?  Everything seemed to check out, although points weren't lasting 
as long as they should.  The dizzy has a little movement in the shaft, but 
the timing and dwell were still solid.

Uh, oh, I thought, must be the ring in no. 3.  Mucho dollars needed to pull 
it apart.  AAaaarrrgh - I bought this car because it had supposedly been 
through an engine rebuild about 20,000 miles ago!

A lot of suggestions were made, some by you lot (thanks for the input)
But here's the answer, and it's something I've never come across before.
The weirdest part of this was that it was just one cylinder.  Having said 
that, no. 1 sometimes looked a little blackened, too.

So, what's actually been going on is that the accelerator pump/choke circuit 
has been staying open, feeding too much fuel into the Solex's.
Apparently they feed into the front choke of each carb - No's 1 & 3!

Now, that's enough to create headaches, but at the same time, I DID have a 
problem with ignition.  I've had an immobiliser fitted to my car, and it 
seems that the guys installing it bypassed the switch to the balast 
resistor, which meant the coil was getting full power all the time!  Even 
when she was running on all four, she was sometimes a bit hesistant and 
missing - but it's hard to tell what's up when the various symptoms overlap.

Anyway, I thought you guys ought to hear about this.  Lou Mondello figured 
it out when a couple of other cars came in with carby problems that produced 
similar symptoms - lots of smoke in one case, and blackened plugs on 1 & 3 
in both cases.  People with Solex's take note!

Thanks for the advice, everyone - I'm going for a drive tonight!

Cheers,

Steve
(Really, really, happy roadster owner!)
1968 2000 Solex
_________________________________________________________________________

<Prev in Thread] Current Thread [Next in Thread>