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Espri3

Esprit HCI Fuel Issue please help

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I have a 1986 Turbo Esprit HCI with K Jetronic system; Australian delivery

 

I have just replaced the fuel accumulator which was dripping, and fuel filter.

It seems that in the months of waiting for these new parts the fuel pumps don't work.

 

There is no buzzing of fuel pumps at 'ignition on' (should there be?), the car cranks over no problems, then there is a buzzing for a few seconds after cranking stops. I never touched any wiring

 

I have checked all fuses, no issues.

 

I have put in fresh fuel.

 

When I 'crack' the fuel line in the region of the new filter there is only a small dribble of fuel, no apparent pressure. Do I need to 'bleed' the fuel system? Are the pumps blocked? Can they be dismantled and cleaned? Is there any way of testing electrics etc?

 

Esprit3

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Geoff,

 

First, check the inertia switch with VOM. It should measure 0 ohm with the plunger pulled up. 

Next, look for a bad terminal connections at the relay(s) sockets.

"Jumper " the pump socket terminals to see if pumps are spinning.

Proper connections to jumper pumps at the relay sockets were noted here:
http://lotusracer.home.mchsi.com/lotustipspage2.htm

But it seems it is gone.  I'll draw a sketch and send you.

Meanwhile:

Remove both pump relays. Make two “jumper” wires with 2 spade terminals on each end. Plug one end in the relay socket middle slot towards the front of the car (#30, black wire), and the other end in the slot towards the rear of the car (#87, banded wire). You should jumper the primary pump FIRST (the relay socket to the LEFT), BEFORE you jumper the secondary pump (RIGHT relay socket). Otherwise, or you could actually damage the secondary pump by running it dry.
Keep both pumps running for a minute or two to purge air bubbles from fuel lines.
Pumps should “hum” and stay cold. Any “grinding” noises or complete silence from the primary pump indicates an electrical trouble. If pump blows the 15A fuse – pump may be jammed.

If primary pump does not work efficiently or provide enough fuel to the secondary pump, the latter starts cavitating, which sounds like a “grinding” noise. Listen to each pump with a mechanic’s stethoscope. Primary pump provides the volume and secondary pump provides pressure.
To stop the pumps, disconnect the secondary pump first and the primary after that, or disconnect the positive battery cable. Remove jumper cables, replace relays. Note: Inertia Switch has no effect on this procedure.

 

Edited by MrDangerUS

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Surely, with the plunger UP, the inertia switch should be open circuit...and thus OFF and the fuel pump disconnected? Unless it's different from the 82 Turbo.....where it is ON and thus 0 ohms when the plunger is down.

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K-Jet systems usually have a connector on the top of the fuel distributor which has to be removed to allow the fuel pump to run without the engine running.

 

The connector goes to a contact in the FD which energises the pump via the fuel pump relay when the air sensor plate is slightly pushed by intake air passing through it with engine running.

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