john116

I have a problem with my 1957 Oldsmobile 98, which has stumped me. On steep hills, or on emergency stops (when the car lurches forward/downwards) the engine just stops running. Testing it on a steep hill, driving up the hill, if I take my foot off the accelerator, the engine dies. I can restart it again straight away, but it will stop if I don't hold down the accelerator.


On the flat, it idles perfectly. My car has the J2 option, which does work although obviously at idle speeds it won't be doing anything.


The car has an automatic transmission. Apart from this problem, it seems to drive normally, although one other thing I've noticed is that it's often hard to start, requiring much cranking. This happens whether it's been left for a day, or just a few minutes after being used.


I've checked the float level, fuel tank pick up (although as it dies so suddenly I didn't think it would be fuel tank related).


Any thoughts? I'm stumped!

oldcutlass

What is your dwell, timing, and idle speed set to?

john116

Timing and idle set as per service manual, no dwell, electronic ignition installed.

Not sure that would make any difference though whether it's on flat ground or a hill.

oldcutlass

Check your fuel line before the fuel pump as they get soft, crack and suck air. Make sure your timing advance is working properly? Make sure the throttle is set correctly, and the butterflies on the unused carbs at idle are closed.

pete324rocket

Check the fuel float level in the carb. I know that hard right or left turns and stalling is because of improper float level, a hill may be similar.

Tedd Thompson

Hard start is very common with today's gas with these era cars.Often my car will need 10 or 12 cranks to get things going after a three day rest. I don't have a idea on the stall on a hill unless somehow your gas pickup is sucking air in that position...Just a guess...Tedd

Ozzie

It sounds like fuel/air related. As has been said, be sure that the end carburetors are closing completely and that the fuel pump to chassis hose is not sucking air due to cracks. Probably a fuel pump check for pressure and capacity is in order. The manual says that the pressure should be 4 - 5.25 pounds. I once had one that was sucking air around the perimeter of the fuel diaphragm and wouldn't move the fuel after sitting for a while. If yours has the glass bowl on the pump, be sure that there is no leak or congestion there. Also look for any congested fuel filter elsewhere. If all that checks O.K., then you may have to go inside the center carburetor and look closely at the float & needle/seat.