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Hello,

For frustrating reasons I have to drain and drop the fuel tank again on my 49 Deluxe 22nd sedan (288). What makes it more complicated is that the gas gauge isn't working, something I hope to address while the tank is off. Does anyone happen to know generally about how many gallons per minute at idle the 288 will go through? I have a 5 gallon emergency tank but I'd like to go through as much as possible to avoid unnecessary gas transfers in the driveway.

Thanks!

I think it would need to idle almost all day to make a significant difference in tank level. The fuel pump specs say it will deliver 1 pint in 45 seconds (no RPM given so am going out on a limb that engine is at spec'd idle speed). That flow rate would only happen if the outlet was wide open and pump was able to discharge freely. With the float and needle valve in the carb shutting flow down to almost nothing I doubt there would be GPM as much as there would be OZs per ??. With a car getting maybe 10 mpg with the engine running at around 2000 RPM I expect it would probably be a very small number of OZs. Might be an interesting experiment to have something like a 1 gallon container plumbed directly to the pump and see how long it would take to empty a measured quantity at idle.

On the non functioning gauge, when you have the tank out you might take the opportunity to cut a hole in the trunk floor for access to the sender next time. Done neatly and with a cover plate the hole would be barely visible. If you are fortunate enough to still have the trunk mat then the work would be invisible to the casual look.packardinfo.com/xoops/html/modules/newbb ... .php?post_id=186125#forumpost186125

FWIW, 1 pt in 45 sec is 1/6 GPM

So at 1/6 GPM at free flow, I would guess by the time the carb restricts flow to what the engine needs at idle it would maybe be a quarter or less of that amount.

Packard got more sophisticated in 1955/56 in giving fuel pump specs for the Carter pump. On the Packard blue print for the pump they state "20 gallons per hour at 1950 camshaft rpm and a 16" head".

As far as the OP's question, just a wild guess but at idle I'd think you'd go from dawn to dusk to burn off a couple of gallons.

A modern efficient 5.0 litre V-8 is ingesting 31.5 pounds of air and burning one gallon of fuel in around 2.83 hours at 711 rpm idle.

So the rich idling Packard motor should burn a gallon at idle every 1.5-2 hours. However, that kind of idling is not good for the motor.

Well... thanks for the info! Looks like I'll have to find a better way to drain the tank. At least this helps me in my calculations so I don't run out of gas out on the streets! Right now the broom handle method is my gauge, though it's also an estimation largely because I'm not sure how inches of gas on the handle equates to gallons in the tank! It's a fun dynamic keeping it topped up so I don't run out but also with the goal of running it down to empty it.

Fortunately Packard tanks have a drain plug but you have to be very careful trying to free it. If you don't also hold the piece into which it is inserted, the whole thing will turn and would then have to be brazed.

It fairly straightforward to just put out the tank but if you're keen on pumping it out (and impossible to get it all out that way), then use a high-volume electric pump plumbed in to the front of the fuel system just before the engine's pump and let it run. I did that on a 1965 Cadillac Fleetwood and got most of it out enough to be able to put in some fresh petrol and do it again several times until it was reasonably clean.

An easy way to empty the tank without risking damage to the drain plug is to siphon. Have we forgotten how to siphon? All you need is a length of tubing.

The last time I siphoned gasoline I ended up swallowing some. The doctor said to eat bread (apparently to absorb it), then to call in the morning if I wasn't dead yet. It could still taste it weeks later! So, no, I haven't forgotten about siphoning but will not do it with anything but water.

Having said that, there are now very handy siphon pumps that can get the process started a bit more safely. I'm not sure who sells them generally but I found mine in a marine store and was like a small rubber bellows.

EDIT: Apparently Home Depot sells them and shows a pump of the sort I recently bought for another purpose as a fluid transfer pump. I didn't realize that it was also a siphon pump!