ConcoursMustang Forums

Restoring - General discussions that span across many different groups of years and models => Drivetrain => Topic started by: adam8888d on August 24, 2022, 04:55:27 AM

Title: 390fe warm starting
Post by: adam8888d on August 24, 2022, 04:55:27 AM
Hello everyone. I noticed the other day that when i start the 68 mustang from cold. It starts instantly. When i ever go anywhere and the car is left for more than five minutes. The car seems to turn over quite a few times before the engine fires up. Has anyone else had this problem? I thought at first it could be fuel evaporation. But if this was so. The car would not start instantly when cold.  Regards
Title: Re: 390fe warm starting
Post by: Deuce on August 24, 2022, 11:22:03 AM
Have similar issues with our 67 2V 289 C code. 

Best explanation I've heard:  Ethanol-blend fuels are more volatile, and will evaporate rapidly in a hot engine with a vented carburetor float bowl.

And it will take some cranking over to start the hot engine while the float bowl is refilled by the fuel pump.  In a cold engine, fuel evaporation doesn't happen as quickly, although sitting a for few days may bring on the same symptoms.

If you try to start the hot engine within a few minutes after shutting down, it likely will fire quickly.  With a longer interval, the still-hot engine will start only after the starter motor cranks for a while.     
Title: Re: 390fe warm starting
Post by: Bob Gaines on August 24, 2022, 11:38:39 AM
Hello everyone. I noticed the other day that when I start the 68 mustang from cold. It starts instantly. When i ever go anywhere and the car is left for more than five minutes. The car seems to turn over quite a few times before the engine fires up. Has anyone else had this problem? I thought at first it could be fuel evaporation. But if this was so. The car would not start instantly when cold.  Regards
No short answer. It could be caused by multiple things. Assuming a Holley on a 68 390 some of the first things that come to my mind is that internally the carb with its pressurized fuel from running is faulty bleeding past the needle and seat allowing fuel to drip drip drip into the engine while sitting and somewhat flooding the engine with a over rich fuel to air mixture causing the hard starting when hot. It may be as simple as changing the needle and seat in the fuel bowls and re adjusting the fuel bowl floats. Possibly adjust your starting method when hot to help live with the problem if you don't fix it. You might try varying methods like when hot not pumping the peddle and see if that helps or a different method of holding to the floor like with a flooded engine makes a difference . You might find a different starting method helps with the hot starting better then when cold if living with the problem and not fixing it.  Just a couple thoughts that come to mind .Best of luck regardless of if solving or living with the problem.
Title: Re: 390fe warm starting
Post by: adam8888d on August 25, 2022, 05:40:57 AM
Thank you for your replies. I noticed reading through the net that this problem has come up many time with the fuel cooking so i have started by removing nearly 2 foot of fuel line as the feed to the carb came in from the back. I will look into installing a insulated gasket to go under the carb also if this does not change anything[/img] regards to all, I will report back in a few days.
Title: Re: 390fe warm starting
Post by: J_Speegle on August 25, 2022, 08:08:18 PM
Hello everyone. I noticed the other day that when i start the 68 mustang from cold. It starts instantly. When i ever go anywhere and the car is left for more than five minutes. The car seems to turn over quite a few times before the engine fires up. Has anyone else had this problem? I thought at first it could be fuel evaporation. But if this was so.

Nothing new and very typical of most cars of this era. Often associated with new/fresh engines also. Things like heat soak of engine and starters. Vapor lock and so on all add to the issue


The car would not start instantly when cold.  Regards

Same thing here. These are not computer controlled cars nor injected ones so I hope your not expecting them to start like one or comparing them to new cars
Title: Re: 390fe warm starting
Post by: midlife on August 25, 2022, 11:02:12 PM
Nothing new and very typical of most cars of this era. Often associated with new/fresh engines also. Things like heat soak of engine and starters. Vapor lock and so on all add to the issue


Same thing here. These are not computer controlled cars nor injected ones so I hope your not expecting them to start like one or comparing them to new cars
Sigh...they don't make things like they used to, do they?