Starting from cold with Dellortos

PostPost by: mbell » Fri Jan 02, 2015 8:37 pm

Are you sure there no some kind of air leak that allows fuel to drain back to the tank?

Only experience this on diesel vehicles but can't see why a petrol car with out an elec pump couldn't suffer from similar problems.
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
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PostPost by: rgh0 » Sat Jan 03, 2015 11:20 am

If the car is not run regularly then the fuel in the carb bowls evaporates. it take some cranking for the mechanical pump to refill the carb. Thus the quick start once the carbs are refilled with the bulb pump.

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PostPost by: jimj » Sat Jan 03, 2015 1:20 pm

But my Sprint engined S3 with a mechanical fuel pump fires up with, maybe, only 10% of the churning after standing for a while. That`s on Webers but it shouldn`t make much difference. Both cars have been set up on a rolling road.
If there were air leaks in the fuel line wouldn`t petrol leak out? at least enough to smell in the garage? I`m thinking a weak pump which is overcome once the engine has fired up. At least, now, I know it`s definitely a fuel delivery problem.
Jim
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PostPost by: jimj » Wed May 13, 2015 9:17 am

Hip hip times 3. The car having done just 1000 miles in a year, we use it sparingly, I booked it in for MOT, service and general torque down, fluids change etc. I use Riverside Engineering in Whaley Bridge, who I have nothing but the highest regard for. Gareth elanman now uses them, as does my pal John with his M100 and TR4, and now pal Mel with his 100/6.
I told them to just keep the car, checking everything fuel related, and trying starting the car only after it had been stood at least overnight. They did fix a tiny, tiny air leak in the boot where the rubber hose connects to the nylon which improved matters slightly and then discovered just the smallest of (evaporating) leak under the carbs. It was the accelerator pump gaskets/diaphrams. They looked fine but were just slightly perished.
I collected the car on Monday then, this morning, Wednesday, while the air was still coolish I took a deep breath, pulled out the choke and turned the key and brrrrrrrm. Hooray times 3.
Jim
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