Mk1 [tech] - Addition of pre-pump?

[vwtype53@yahoo.com (Benjamin Harder)]

Thanks Drew
  This does help... I think I will start by getting ahold of
a transfer pump assembly and test-fitting it to the tank in my 80.
Then the feed and return lines will need to be routed.  I suspect 
this won't be too big of an issue.

Thanks for the help,

Ben


--- Drew MacPherson <drew@scirocco.cs.uoguelph.ca> wrote:
> 
> The biggest issue to resolve will be if the later style sender (with 
> transfer pump) uses the same tank fitting as the earlier style sender 
> only.
> 
> I expect that this is the case.  The next challenge will be fitting the 
> transfer pump into the tank.  The 84.5+ cars have a slightly larger tank 
> with a small dish at the bottom where the strainer for the transfer pump 
> collects fuel from.  IIRC the transfer pump assembly on the sender is 
> spring loaded to ensure that it sits on the bottom of the tank (I know 
> this to be the case with A2 transfer pumps, but it's been a few years 
> since I replaced the one on the scirocco.)  It may be necessary to modify 
> the transfer pump or the line that connects it to the sender in order to 
> allow the pump pickup to sit at the bottom of the tank.  Also, a number of 
> pre-84 A1 tanks I have been into have baffles in the tank around the 
> pickup tube (which runs out the bottom front corner of the tank)  It may 
> be necessary to find an aftermarket tank (without these baffles) or remove 
> them (not sure if this is possible without destroying the tank.)  The key 
> is to ensure that the pickup strainer sits as close to the bottom at the 
> lowest part of the tank.
> 
> You will also need to block off your current feed and return connections 
> on the tank and re-plumb your fuel lines so that the transfer pump routes 
> to the main pump (good idea to put in a small resevoir or later Scirocco 
> "filter/resevoir" to keep the main pump from overrunning the transfer 
> pump) and the return line goes to the top of the tank.
> 
> Does this help at all?
> 
> Drew
> 
> On Mon, 17 Mar 2003, Benjamin Harder wrote:
> 
> > AFAIK, none of the mk1 rocco's came with a fuel pre-pump installed.
> > I would like to know (besides wiring issues) what, if any, issues there
> > would be to install a pre-pump?
> > 
> > The main reason for asking is an experience I had with my former '81
> > while autocrossing... I had about 1/4 to 1/3 tank of fuel...
> > coming around a long sweeper (left-hand turn) and then onto a straightaway
> > the car would starve itself for fuel and sputter.  Not good while trying
> > to race!  So, the issue was obvious to me... the car really needs a 
> > pre-pump, or of course just a full tank of fuel... which isn't always
> > the best idea on the track...
> > 
> > Anyhow, any experience with this one would be appreciated!
> > 
> > 
> > =====
> > Benjamin Harder
> > 86 Scirocco 16v
> > 80 Scirocco (new engine is almost ready!)
> > 93 Passat GLX
> > 
> > http://www.geocities.com/vwtype53/
> > 
> > __________________________________________________
> > Do you Yahoo!?
> > Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
> > http://platinum.yahoo.com
> > 
> > _______________________________________________
> > Scirocco-l mailing list
> > Scirocco-l@scirocco.org
> > http://neubayern.net/mailman/listinfo/scirocco-l
> > 
> 
> -- 
> /=============================================\
> |  84 Wolfsburg Edition TurboDiesel Scirocco  |
> |    http://scirocco.cs.uoguelph.ca/gtd       |
> \=============================================/
> 


__________________________________________________
Do you Yahoo!?
Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
http://platinum.yahoo.com