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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,563
Fuel System Refresh

The fuel system on this car is now cascade failing as I put more miles on it. Have you seen that Mel Gibson movie where he is cryogenically suspended in time for 50 years and then revives only to age rapidly to where he should have been? That's what is happening to this car. It was stored in a barn the better part of 20 years and now all the age is coming home to roost.
This was however expected and thus the topic of this thread.

Pig rich under all conditions to the point where periodically the engine will bellow smoke out the rear and struggle to idle.
Test Method:
Verify fuel pressures.
System pressure is low (83psi) indicating weak pumps. Changed out front pump with OEM replacement, purchased -044 Bosch for rear pump replacement but need special fitting to make it work. Will change out when part arrives. Engine runs somewhat better with new front pump. Pressure up to 85psi which is still weak.

Whenever I get gas the engine runs very badly upon startup and will not idle.
Test Method:
Check bleed down time on fuel pressure after shutdown.
Irratic response as some times pressure will hold and sometimes it will not. Indicates faulty fuel accumulator. Changed out accumulator and engine immediately starts perfectly.
Note - the fuel filter and accumulator are easier to R&R than it looks so don't be scared to do it.

Here is one of the hazards we have down here when your cars sits too long. This little beasty was guarding my rear fuel pump.

RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 09-15-2012, 10:58 PM
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