[Vwdiesel] Leaking IP ; Fuel in the Sump

[Val Christian]

Ref the posts below...


I also have a ME, which is a non-turbo 1.6 on a 91 Jetta.  I recently
reported fuel in the oil sump, and a timing problem.  The timing has been 
resolved.  The fuel in the sump has also been resolved.  Loren deserves
credit on this one.  Here's what was happening:

A failure in the IP, caused fuel to be fed into the vac pump.  It was a
pretty good flow.  Loren suggested that the fuel contamination in the 
oil sump exceeded the rate the injectors were capable of.  So I went 
looking elsewhere.  Hayden shared his understanding of the fueling 
management of the 1.6 NA engine.

Like the post below, I have an IP which ends in ...710 N.  It has
a diaphram on the top, which is similar to what the turbos have
(it may even be the same), except that it operates the opposite.
The top of it is vented to the atmosphere, with a rubber boot
having a opening in it.  The bottom of the diaphram is connected
to a banjo fitting which has a 3mm vacuum/fuel return hose on it.
That line runs to a T fitting.  The driver side of that T goes to 
an inline orifice, used to limit flow.  The passenger side of the
T goes to a diaphram device near the fuel filter.  I can't tell
you exactly what is happening with this circuit, perhaps Hayden
can, but it appears that it is sensing the absolute pressure one is
driving at, and using that to adjust fuel metering.  Hayden suggested
it was probably an emissions thing.  

In my particular case, the failure was causing fuel to flow from the pump,
through the vacuum orifice, into the vacuum pump, and discharged into
the engine sump.  As a possible workaround, I disconnected the line from the 
IP to the compensation lines with the T fitting, and I found that 
fuel continued to leak.  First it seemed that fuel was oozing from
the hose where i plugged it.  So I plumbed it into the return line 
going back to the tank.  Things were still leaking, then I discovered 
fuel oozing out of the rubber boot on the top of the diaphram.

So at this point, it seems that I need to do some kind of IP repair,
although it is not exactly clear to me what will need repair.
So fi anyone knows, please speak up.  (Otherwise I will continue to 
pester Loren and Hayden.)

So this ties in with the posts below, in that I can add a little 
understanding on the fuel de-enrichment mechanism for high altitude
driving.

Val














> --- In dieselvolkswagenclub at yahoogroups.com, "Wes Engle" 
> <hankbrass at ...> wrote:
> >
> > I am in the process of swaping a 79 CK (1.5) out of my 81 pickup in 
> favor of an 89 ME (1.6). I have a couple of questions. On my old 
> motor there is a crankcase breather plate that has a hose going to 
> the vacuum pump. The newer motor does not have this. Can I just run a 
> hose to my brake booster on the newer one? The other question 
> involves the injector pumps. The one on the ME has a diaphram like 
> pot on the top of the pump. I think this is a boost inrichment gizzy 
> for a turbo? On the back of the pump it has 2 banjo fittings. a lower 
> one with two hose barbs, large and small which I think are the 
> injector overflow and tank return line connections. The upper barb is 
> VERY small. Can I just leave this unconnected as the motor is not 
> turboed.
> > Wesley A. Engle
> > NRA Benefactor Member
> > (and proud of it!)
> 
> The diaphram on top of the injection pump is for turbo enrichment, it 
> shoul have a barb fitting on it for the boost signal. The other very 
> small barb fitting if for the return lines from the injectors. There 
> should be two larger fitting one for fuel supply and one for fuel 
> return from the tank.