67oldsdelta88

Hello all. My 425 will only cold start if I hold the choke fully open from under the hood while another person cranks. Once it does start I can let the choke close and it will idle. Any suggestions? Thanks

joe_padavano

What is the air temp and engine temp when this happens? All temps? Just when the air is hot? Hard to diagnose without more info.

m371961

Are you hitting the throttle once to the floor,release, cranking and not pumping throttle? On mine, that's the trick. Any pumping after that and it tends to flood.

67oldsdelta88

Outside air temp is mid 70's and the engine is cold (first starting attempt of the day). I usually pump the throttle 2-3 times and then crank the motor then have to keep pumping throttle to fire.

joe_padavano

Next time, before starting the car, remove the air cleaner and pump the gas pedal one time. Look at the choke plate. It should be nearly closed, but not completely closed.

Also, does this happen when the car has been sitting overnight only, or for a few days. Today's gasoline evaporates quickly from the float bowl and often it will take additional time for the fuel pump to refill the carb after the car has been sitting for days. Often, weak check valves in the fuel pump can make this worse, as the pump doesn't work as well as it should.

67oldsdelta88

It happens after sitting for a couple of days. I will try what you suggested with just pumping the throttle once and look at the choke plate. I am wondering if the choke even functions at all, I was looking at some shop manuals last night and it looks like I might be missing one of the tubes for the heat stove. I've attached a pic of what is on the intake. Should there be another tube on the left side? Looking through some old shop manuals last night it looked as if there should be one going to the top of the carb...

joe_padavano

Yes, but the one that goes to the top of the carb only serves to supply filtered air to the choke (and eventually sucked into the engine, thus the use of filtered air). Without the tube you are pulling unfiltered air into your engine. Not the best for the engine but it won't affect the operation of the choke. The only way this would be a problem is if the missing tube has allowed the choke stove in the intake to get plugged somehow. More to the point, this would prevent the choke from opening once the engine was warm. It doesn't affect choke operation when cold.

Fun71

That hole on the left side of the coke heater is the air inlet. There originally was a metal pipe that ran to the air cleaner (and attached to it using a short section of rubber hose) so the choke pulled in clean, filtered air. If there isn't anything blocking the inside of the heater tube that would prevent air from passing through and it should be functional.

Many years ago that part broke on one of my cars and I made a new one using a section of copper tubing that I wedged into the hole and it worked great. The originals were inserted then crimped to keep them in place.

67oldsdelta88

Thank you guys for the input! This forum is great and very helpful. I purchased this 67 delta 88 back in 2008 when I was 21 as I always had a love for classic cars growing up but never had the chance to be around them/work on them (though we did own olds and buicks, I only every learned basic car maintenance). I drove it for a year before it broke down on me in my driveway and I pushed it into the garage. Over the past years I would do a little work on it, mostly cleaning the engine bay as it was a disaster. Pulled it out of the garage a month ago and decided to get it running again (poorly). I guess what Im saying is I will probably have many more questions as I continue to work on it and get it back on the road. It's nice to have a helpful community with a wealth of knowledge about these old cars.