new gas tank

[Twan B.]

I've just took my old gas tank out of my '65 Conv. because of 3 old repairs that now are leaking.
I'am installing a new gas tank with all new rubber lines. What should i do to get her started when i fill her up, there is no fuel in the system , should i play with the accelerator? There is a chance for backfire and i maybe loose my new muffles.

Twan
#44079

[Paul J.]

Re: new gas tank

I've just took my old gas tank out of my '65 Conv. because of 3 old repairs that now are leaking.
I'am installing a new gas tank with all new rubber lines. What should i do to get her started when i fill her up, there is no fuel in the system , should i play with the accelerator? There is a chance for backfire and i maybe loose my new muffles.

Twan
#44079

I assume that it is carburated and the carburator bowls are still full. Just start it as you would normally. Any air in the lines should equalize in the bowls. If the air gets to the jets it could stumble and die, then I would either play with the accelerator or just crank it until it starts.

I've never heard of the mufflers being blown off by a backfire, and there should be no chance of a backfire if the timing has not been changed and you have'nt overloaded the carb.

Paul

[Jack H.]

Re: new gas tank

The system was initially dry when these cars were assembled...

It might take a bit more initial cranking time for the fuel pump to fill the pipeline, but you're not going to blow your exhuast off!

[Lynn H.]

Re: new gas tank

I assume that it is carburated and the carburator bowls are still full. Just start it as you would normally. Any air in the lines should equalize in the bowls. If the air gets to the jets it could stumble and die, then I would either play with the accelerator or just crank it until it starts.

I've never heard of the mufflers being blown off by a backfire, and there should be no chance of a backfire if the timing has not been changed and you have'nt overloaded the carb.

Paul

I agree with Paul about getting your car started, but as far as the mufflers and backfiring that can and has been an issue in many cars I have seen. I even have an example of this I will try to post a picture of later in the day. Seems most of the instances I recollect involved big blocks, but I am sure the problem can happen with SBC's also. If the floats stick or are not set properly, excess pumping of the accelerator, and I'm sure some other conditions, can result in the "dumping" of fuel into the exhaust (which can collect in the mufflers). I have been present when it has happened and it is like a bomb going off (kinda what it is). I have seen this literally destroy brand new mufflers, so it is something that is possibly, but not something I would expect form the installation of a new tank, in and of itself.
Lynn

[Donald O.]

Re: new gas tank

I assume that it is carburated and the carburator bowls are still full. Just start it as you would normally. Any air in the lines should equalize in the bowls. If the air gets to the jets it could stumble and die, then I would either play with the accelerator or just crank it until it starts.

I've never heard of the mufflers being blown off by a backfire, and there should be no chance of a backfire if the timing has not been changed and you have'nt overloaded the carb.

Paul

A back fire will do absolutely nothing to the exhaust system. A post fire most surely can do some serious damage to a muffler.
Whats the difference you ask.....
A back fire goes up and out the carb hence backward firing.
A post fire is like when kids in the 50s & 60s you could cruise along in gear, shut the ignition off for a few seconds, switch it backk on and sometimes you could get a loud bang. This was the fuel igniting in the exhaust system.
class dismissed

[Terry M.]

Re: new gas tank

I don't recall the circumstances (it was not replacement of the fuel tank, though), but there was an explosion in the original exhaust system of my 1970 that blew the right hand muffler open like a grape. It happened years ago, so I recall the results and not the origins. You guys can call it whatever your settle on after the argument -- I don't care what you call it. I call it trashed right hand exhaust system.

We can debate how common it is, or what causes it, or even what to call it -- but don't tell me it can't or hasn't happened.

[John H.]

Re: new gas tank

The system was initially dry when these cars were assembled...

It might take a bit more initial cranking time for the fuel pump to fill the pipeline, but you're not going to blow your exhuast off!

Just prior to the car-start operation on the Final Line, the float bowls were primed with gasoline through the bowl vent tubes so the starter didn't have to crank and crank to get fuel from the tank through the dry system and deep enough in the bowl to cover the jets. We did this in every assembly plant until fuel injection came along with an electric pump in the tank.

Just fill the float bowl through the bowl vent tube with a syringe or plastic ketchup dispenser bottle and start it up - it'll run fine on the fuel in the bowl until the fuel pump pulls fuel from the tank to the carburetor. I do the same thing at the end of winter storage, as the fuel in the bowls has evaporated.

[Lynn H.]

Re: new gas tank

I don't recall the circumstances (it was not replacement of the fuel tank, though), but there was an explosion in the original exhaust system of my 1970 that blew the right hand muffler open like a grape. It happened years ago, so I recall the results and not the origins. You guys can call it whatever your settle on after the argument -- I don't care what you call it. I call it trashed right hand exhaust system.

We can debate how common it is, or what causes it, or even what to call it -- but don't tell me it can't or hasn't happened.

That was kinda what I tried to say!!
Lynn

[Ian H.]

Re: new gas tank

Just prior to the car-start operation on the Final Line, the float bowls were primed with gasoline through the bowl vent tubes so the starter didn't have to crank and crank to get fuel from the tank through the dry system and deep enough in the bowl to cover the jets. We did this in every assembly plant until fuel injection came along with an electric pump in the tank.

Just fill the float bowl through the bowl vent tube with a syringe or plastic ketchup dispenser bottle and start it up - it'll run fine on the fuel in the bowl until the fuel pump pulls fuel from the tank to the carburetor. I do the same thing at the end of winter storage, as the fuel in the bowls has evaporated.

John: Where is the bowl vent tube located. Can you show us with a picture? My '67 3810 Holley requires about three 7 second cranks to start after sitting more than 2 weeks as the bowl must be emptying. I'dd like to try your method too.

Thank you,
Ian

[John H.]

Re: new gas tank

John: Where is the bowl vent tube located. Can you show us with a picture? My '67 3810 Holley requires about three 7 second cranks to start after sitting more than 2 weeks as the bowl must be emptying. I'dd like to try your method too.

Thank you,
Ian

Ian -

Photo of my 3810 below. The primary bowl vent tube is pressed into the boss at the center of the front wall of the choke air horn, and the secondary bowl vent is directly opposite at the rear, sticking up just forward of the air cleaner gasket. Fuel evaporation with today's fuels is quite common if the car sits for more than a few days at a time.

[Larry E.]

Re: new gas tank: Attn: John

Attn: John:
How much fuel do you put in the vent tubes? Till it runs out or just a few
squirts?

Thanks; Larry

[Jim T.]

Re: new gas tank

Ian -

Photo of my 3810 below. The primary bowl vent tube is pressed into the boss at the center of the front wall of the choke air horn, and the secondary bowl vent is directly opposite at the rear, sticking up just forward of the air cleaner gasket. Fuel evaporation with today's fuels is quite common if the car sits for more than a few days at a time.

I have been using the direct injection of fuel in my Holleys for many years with my cars no longer daily drivers. It sure makes a significant enough difference in cranking time that the time/trouble to open the hood and remove the air cleaner top to inject the fuel is no problem for at all for me. I use a large syringe I bought at the CO-OP feed store. Even turning on the key on my other (85-96) factory electronic fuel injected cars after non use I listen for the fuel pump relay to click off before I crank the cars and they start immediately with the fuel pressure topped up.

[Ian H.]

Re: new gas tank

Ian -

Photo of my 3810 below. The primary bowl vent tube is pressed into the boss at the center of the front wall of the choke air horn, and the secondary bowl vent is directly opposite at the rear, sticking up just forward of the air cleaner gasket. Fuel evaporation with today's fuels is quite common if the car sits for more than a few days at a time.

Thanks John. In your photo, those are the two vertical tubes having cuts at a 45 degree angle.

[John H.]

Re: new gas tank: Attn: John

Attn: John:
How much fuel do you put in the vent tubes? Till it runs out or just a few
squirts?

Thanks; Larry

Larry -

I use a plastic ketchup dispenser bottle (like you used to find on the table at small restaurants) and fill the primary bowl until I see fuel at the boosters.