1977 Regency 98 - Cold start, stall, then will not restart.

[Guest emarkay]

1977 98 Regency with stock Olds 350 and stock M4MC Quadrajet, 77K miles.

Carb rebuilt, fuel filter replaced, fuel pump replaced, lines checked, no apparent leaks, new rubber hoses, engine strong (no smoke), car well maintained.

About every 4th or 5th time, car will start up fine, and idle at normal fast idle speed, AND THEN either a minute or so after starting OR after pulling out from stopped position, car will stall and die. Nothing can be done to get a restart - no closed throttle, pumped or floored. - EXCEPT BY "PRIMING" - see below!

****Clue #1: No fuel found in accellerator pump upon immediate inspection of carb at time of stalling. (That is why I did all the above repairs.)

When I rebuilt the carb, I cleaned it and found little evedence of dirt and no evedence of prior rebuild. I replaced needle and seat, and tripple checked smooth operation and float level, and check ball, and all gaskets, and did not see any OBVIOUS evedence of any internal leaks (Main discharge tube plugs seem to be a problem?), and used specs found in 1977 Olds Shop Manual

One other possibility I have seen is the "Siphon break passages" (may not be applicable to this MY car) and also, the vacuum breaks APPEAR to hold vacuum and function with a gradual (2 sec or so) return when vacuum is released. All vacuum hoses have been replaced on carb, and all others EMISSION hoses (cannister, EGR, THERMAC, DTVS,) are plugged. Timing is about correct (advanced to slight pinging at WOT under load) , plugs wires and cap/rotor are new. Weights were rusty but are free.

****Clue #2: If I pour raw gas down the primary (a desperation move the first time this happened) THE CAR WILL START!!!! AND RUN FINE FOREVER!! Ocasionally I need to ""prime"" it twice to get it to stay running.

This has been happening for months now (winter and summer) and there is no pattern to it except with a cold engine and to pour raw gas down carb to get it to run!

HELP!!!

MRK

PS: yea I posted this in December, and thought the carb rebuild fixed it - is "seemed to" but I finally got stranded big time today and am now getting frustrated!

[jimde]

Once owned a 1977 Delta 88 Indy pace car edition with the 403ci. engine. Never had a problem like yours. When I sold it it had over 110,000 miles on it and still ran good. Sounds to me you did everything you could on the carb. As a last resort get a new carb!

[Oldsmaniac]

Ok it seems lack of fuel is the problem....could be spark related as well but from what ya said it seems like fuel. I assume you replaced the accelerator pump when the carb was apart. The rubber cup will crack or shrink over time and not give a shot of gas when needed. Will also make engine stall when trying to accelerate from a stop. You say you found no fuel there. The carb would have to have been disassembled right then to determine that so ya could look in the well where the plunger rests. im thinking you worked the throttle by hand and saw no squirt action.....leading to accelerator pump failure or no gas in the carb. So if there really wasnt any gas in the carb there are 3 likely reasons besides having an empty gastank. The first would be a clogged filter or stuck check valve in the filter. Filters can be had without the check valve. The second reason is fuel pump trouble. Since the pump was replaced ya might check for a cracked hose from the tank. Pump may be sucking air and not fuel. Also make sure vent for tank is ok....sometimes the cap is vented. Ya may try starting with the fuel tank cap off. The last thing could be the filter sock in the gastank is clogged....If it will start with gas dumped down the carb every time spark is not the problem. You should also check proper choke operation and choke pulloffs. Hopefully the carb was rebuilt with a fresh kit. Gaskets and rubber parts go bad just from sitting on the shelf. Hope ya find the problem.

[Guest emarkay]

UPDATE - finally had time to do more research:

Installed clear fuel filer after fuel pump and before carb. Wouldn't start after letting it sit a few weeks. And yes, this time, the fuel pump is "puffing" AIR!

OK simple, eh?

But why then, after pouring an ounce or 2 of gas down the primaries, the car fires up, and whallah, the fuel pump is now pumping GAS!

I also removed the O-Ring on the fuel cap to prevent a vacuum, so that's not the problem.

Dirty strainer? Then why does it ALWAYS run good after priming?

Air bubbles in fuel lines? Wouldnt it also LEAK gas then?

ANYONE had this sort of thing happen - no fuel in lines till you prime the motor and get it running?

Also, do I need to remove the fuel tank to get the lines and strainer out?

MRK

[Guest emarkay]

FOUND IT.

Rubber fuel line at tank, way above fuel level, had small cracks.

Replaced rubber line line and now clear fuel filter is now over 3/4 full at all times and no more bogging at WOT, and so far, no more no-start.

THANKS FOR ALL THE IDEAS!

MRK