[Fot] No vacuum after Spitfire engine rebuild

[Tim Murphy]

Ryan can also attest to the problem caused when the intake manifold on the
TR4 is not seated on the pins properly!  If you've got SU's you should be
able to see the pistons moving up and down quite a bit as you are cranking
it with the ignition shut off.  If not, you've got a massive intake leak
someplace.  Now we check to see if the pistons on the SU's are moving up and
down after we have the manifolds off to make sure we don't have that
problem.

Tim

-----Original Message-----
From: fot-bounces at autox.team.net [mailto:fot-bounces at autox.team.net] On
Behalf Of Tony Drews
Sent: Sunday, April 25, 2010 2:48 PM
To: Bill Babcock
Cc: fot at autox.team.net; George Harmuth
Subject: Re: [Fot] No vacuum after Spitfire engine rebuild

That's an excellent point.  On the TR-4, there are pins on the side 
of the head the that fit into the intake manifold.  If you misalign 
the manifold a bit you can end up with the bottom of the manifold 
held away from the head by the pins leaving a huge gap - easy to make 
that mistake.

- Tony

At 02:39 PM 4/25/2010, Bill Babcock wrote:
>I'd also look for a massive air leak.
>On Apr 25, 2010, at 9:32 AM, Tony Drews wrote:
>
> > If it runs on starting fluid, it sure seems like a carburetion / 
> fuel issue.  Did you "degree" the cam when assembling?  Having it 
> off in timing by a tooth can make it run like crap and be hard to start
too.
> >
> > If you've got SU carb's, with the piston removed you should be 
> able to see a little fuel in the jet tube.  A little bit of debris 
> can clog the passage from the float bowl to the jet.
> >
> > - Tony
> >
> > At 02:23 PM 4/25/2010, George Harmuth wrote:
> >> Time query the collective again. My son and I just finished a rebuild
of
> >> his 72 Spitfire (1296, large journal) and I can't get it to run.  The
car
> >> will start up on starting fluid but won't even fire on it's own.
Confirmed
> >> fresh gas to carb, gas in fuel bowl, disassembled carb, cleaned and
> >> inspected, looks OK and was working (rebuilt last summer) before engine
> >> rebuild.
> >>
> >> Think I've tracked it down to no vacuum, either from the vacuum port
(flat
> >> 0 reading on gauge, no fluctuations ) on the carb or gross check,
putting
> >> my hand (or carb sync gauge) over the mouth of the carb. I've removed
the
> >> carb and intake manifold, gaskets etc all look good. Removed the valve
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