Re: [DML] Re: Accumulator Problems

["DMC Joe" <dmcjoe@xxxx>]

Heating of the fuel is a common occurrence is all internal combustion
engines, especially in hot weather. This is the very reason that the fuel
injection system is fitted with a fuel accumulator. The fuel is heated, not
at the fuel tank but as it passes through and around the engine. When the
engine is stopped the fuel sitting in the fuel lines above the engine will
go into "vapor lock" if the pressure in the fuel lines drops below a certain
level. The fuel accumulator maintains pressure in the fuel line to prevent
vapor lock.

I would strongly suggest that you replace your lower pick up hose. Your
description of your fuel pump buzzing is a strong indication that the hose
is collapsing as the fuel warms causing "fuel starvation".

"We're here to help you"

DMC Joe / De Lorean Services / <dmcjoe@xxxx>
Web Site: <www.deloreanservices.com>
.

----- Original Message -----
From: Robert Rooney <dmcvegas@xxxx>
To: <dmcnews@xxxxxxxxxxx>
Sent: Friday, June 23, 2000 4:43 AM
Subject: [DML] Re: Accumulator Problems


> In the summer heat of no less than 105 degrees during the day, with
> lows around 82-85 degrees at night is the enviornment that my
> DeLorean is in. While in traffic the cooling system on the car works
> just fine. But it's when the car is parked that the fuel really heats
> up. When I'm driving there's at least air flow going across the fuel
> tank, but when I'm parked the air flow stops and the heat goes
> straight into the tank. Remember, it gets heat from all sides:
> radiator, coolant hoses, pavement, and from the trunk compartment.
> About 3-4 hours of driving a day is all that the D can stand. After
> about 40 minutes to an hour is when the fuel pump starts to buzz. But
> if I park for a long time and then come back, the pump then buzzes
> almost as loud as the engine. At this point I've had the car stall
> and a couple of times even die on me in traffic. I once even had to
> park out in the middle of the desert for about an hour or so just to
> let it cool off so I could get home.
>
> About 2 weeks ago I started to have a "hot start" problem with the
> car. If the D has sat overnight, then she starts up with a little
> hesitation. But the engine will act like it's flooding untill it's
> heated up. Once turned off, I have about 15 or so minutes to restart
> the engine with minimal hesitation. After that I then have to
> manually fire the cold start valve to get everything started again.
> Thus far I've done the following things to the ignition system: new
> wires, spark plugs, rotor, distributor cap, cleaned the ground
> connection for the starter & fuel pump. The ballast resistors show
> only 2 ohms resistance, and the LAMBDA unit shows a steady 1.5 volts.
> NO fluctuation going to the frequency valve what so ever no matter
> what the temperature of the engine is. The oxygen sensor is new, and
> I know that according to the workshop manual the wire isn't connected
> to it properly, but I haven't gotten to inspecting it yet. With all
> of this in mind, does anyone here have any ideas on what is causing
> this problem? With the new platinum sparkplugs and the high
> performance wires the engine runs stronger then it did before, but
> the hard starting & the pick up hose have really put a damper on
> things.
>
> Now, what do these 2 things have to do with each other? If things
> such as the accumlator and other fuel system components are not
> affected by higher, more constant temperatures, then all I need to
> worry about is replacing the pick up hose. But if heat can damage
> certain fuel system components, then I need to also keep the fuel
> tank cool. Suggestions? I'm pretty much open to any theories that
> anyone may have right now!
>
> -Robert
> vin 6585