1960 Fuel Injection Idle problem

[Sander B.]

hello all

I have put the original FI Unit back on the car today
and started the car ,

it ran quite good at cold
but after a few minutes (when warm )it began to run irregular at idle
what should i check for ? should i adjust the lean stop on the fuel meter ?
the other adjusting screws didnt help solve the problem

the FI unit has been rebuilt in 2000 by John DeGregory ? (every thing looks like new all hoses gaskets etc......) and removed from the car by the former owner

[William C.]

Re: 1960 Fuel Injection Idle problem

start with the cranking signal valve. An easy test is to pinch off the rubber hose from the cranking signal valve to the steel line with the engine showing it's "roughness" when warm. If it clears up, replace the cranking signal valve.

[Sander B.]

Re: 1960 Fuel Injection Idle problem

do i need to block the line to prevent losing the vacuum on the fuel contol diaphragm?

or only pull of the hose from the cranking signal valve

thanks Sander

[Mike McKown]

Leave everything hooked up.

Just pinch the line off to the CSV so it doesn't get vacuum.

When they go bad, t's usually accompanied by black exhaust smoke. If it's not loading up look for a vacuum leak.

[Alan Drake]

Re: 1960 Fuel Injection Idle problem

After you run down all the FI possible problems also look at some regular faults.
I could never get my FI unit to run the way I liked - so I keep working on it instead of replacing it with a carb ( good move since I still have the orignal FI on my car).
Found much latter a leak in the manifold to head gasket.
Also have now upgraded to an electronic control for the spark advanced, set idel at 14 and cruse at 9 - made a big improvement.
Good Luck with problem, just don't always blame the FI as I did.

[G B.]

It sounds like fuel percolation in the spider

First, don't take the unit apart.

Then make sure you have gasoline in the tank with a high (210 degrees) "50% boil-off temperature". Usually in the US we have to buy racing gasoline to get this high spec fuel. Pump premium gasoline here can have a 50% boil-off temp as low as 150 degrees.

After trying 100% "good" gas, I would call John DeGregory himself. You should make sure that he is the one who actually rebuilt your unit. If so, then your distributor was probably rebuilt by Don Baker. Both men do excellent work every time, so I would stop suspecting the FI system at that point and look harder at my engine.

[Sander B.]

runs better now

well i have changed the timing a little (earlier)
now at idle the rpm is steady and the FI responds beter to the adjusting screws

thanks for the advice Sander,