|
Re: 1936 Packard 320 ci fuel issue
|
||||
|---|---|---|---|---|
|
Home away from home
 
|
Is the pressure drop a slow decrease over the ten minutes or is it a step function that suddenly goes from 4.5 to 0?
How long do you have to wait until you can start it again and get 4.5psi? Have you tried isolating the fuel pump and measuring the output?.
Posted on: Today 11:02
|
|||
|
||||
|
Re: 1936 Packard 320 ci fuel issue
|
||||
|---|---|---|---|---|
|
Home away from home
|
Be sure the air vent in your gas cap is not plugged. If you have a replacement gas cap, it's possible it doesn't have a vent.
Posted on: Today 11:21
|
|||
|
||||
|
Re: 1936 Packard 320 ci fuel issue
|
||||
|---|---|---|---|---|
|
Home away from home
|
I vote gas cap as TXgoat said.
Posted on: Today 11:43
|
|||
|
1955 400 | Registry | Project Blog
1955 Clipper Deluxe | Registry | Project Blog 1955 Clipper Super Panama | Registry Email (Parts/service inquiries only, please. Post all questions on the forum.) service@ultramatic.info |
||||
|
||||
|
Re: 1936 Packard 320 ci fuel issue
|
||||
|---|---|---|---|---|
|
Home away from home
|
It can't be the gas cap since I am running for the test, on a 5-gal fuel can with the cap off. The pressure drops incrementally in 10 minutes. It will restart in about 20 minutes with 2.5 psi. completely cold engine then goes back to 4.5 psi, but repeats to 0 psi in about 10 minutes. I don't think I can isolate it any more without making a rig with a cam to operate the pump lever. Any another idea are appreciated! Thanks
Posted on: Today 15:36
|
|||
|
||||
|
Re: 1936 Packard 320 ci fuel issue
|
||||
|---|---|---|---|---|
|
Home away from home
|
Quote:
I was thinking of a rig with a gravity feed gas tank connected to the line from the pump to the carburetor and an output line connected to the pump output going into another tank. This would allow you to observe the pump output directly for changes in stroke volume and pressure versus time. Is your pump the combined fuel and vacuum pump?
Posted on: Today 16:16
|
|||
|
||||
|
Re: 1936 Packard 320 ci fuel issue
|
||||
|---|---|---|---|---|
|
Home away from home
|
Did you check the pump flow rate by disconnecting the exit line from the carb?
My other thought is that maybe a check valve is sticking somehow? 🤔
Posted on: Today 16:17
|
|||
|
1955 400 | Registry | Project Blog
1955 Clipper Deluxe | Registry | Project Blog 1955 Clipper Super Panama | Registry Email (Parts/service inquiries only, please. Post all questions on the forum.) service@ultramatic.info |
||||
|
||||
