# Carb's fuel bowl losing fuel, evaporating **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [March 8, 2024, 9:44pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506 "2024-03-08T21:44:19Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 9:44pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/1 "2024-03-08T21:44:19Z")
Now the Corolla is back on the road and my daily driver, my prior daily driver 50 year old V8 Ford Truck isn’t getting nearly the amount of use. It runs good, but after it sits unused for 5-7 days the fuel in the fuel bowl is presumably evaporating and doesn’t have enough fuel remaining for the engine to immediately start-up. First I have to crank the engine for a few times to fill the fuel bowl, annoying. I got to wondering if maybe there’s a simple solution to this? Spraying a dose of starter spray into the air intake? What if I installed an electric fuel pump with a switch so I pump fuel into the carburetor bowl w/out running the engine? Even simpler if there was a manual fuel pump available for this, using a rubber bulb I’d press a few times to prime the carb? ---
**Author:** ![weekend-warrior](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/weekend-warrior/32/26122_2.png) [@weekend-warrior](https://community.cartalk.com/u/weekend-warrior)\ **Post date:** [March 8, 2024, 9:56pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/2 "2024-03-08T21:56:53Z")
Why not just pump the gas pedal to get gas into the carb. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 9:59pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/3 "2024-03-08T21:59:05Z")
> [@weekend-warrior](#): > > Why not just pump the gas pedal to get gas into the carb. pumping the pedal activates the carb’s accel pump which transfers gas from the fuel bowl to the air-intake, won’t work if the fuel bowl is empty. I generally do that b/c it does help if the fuel bowl has a least some gas remaining. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 10:04pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/4 "2024-03-08T22:04:49Z")
Another idea, I have on occasion popped the top off the carb and filled the fuel bowl directly from a fuel-container. Maybe there’s a way to do that without needing to pop to top off the carb? Removing the top of the carb is a fiddly, awkward job. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [March 8, 2024, 10:05pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/5 "2024-03-08T22:05:25Z")
You asked this same question back in 2021. > [@70's Ford truck carb problem](https://community.cartalk.com/t/70s-ford-truck-carb-problem/180434): > > 302 engine. Autolite 2100 2B carb. Relatively minor problem, but annoying. After sitting 48 hours most of the gasoline in the fuel bowl has disappeared, which makes for longer cranking when starting the engine. When I removed the carb for a bench inspection, the fuel bowl was nearly empty & there was a thick, almost dripping coat of gasoline on the throttle plates. More on one side than the other. The power valve’s vacuum compartment is completely dry. Thinking it still might be a probl… Tester ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 10:08pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/6 "2024-03-08T22:08:49Z")
I didn’t realize there’s rule here that a question can only be asked once every 3 years. Hopefully there is no such rule. In any event, still looking for a practical solution. As I recall that particular problem turned out to be the fuel bowl was not vented correctly, getting pressurized from the engine heat, and gas was being pushed out of the fuel bowl into the throttle valve area. ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [March 8, 2024, 10:10pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/7 "2024-03-08T22:10:48Z")
No rule against it, but it might be more productive to revive the old thread instead of starting a new one. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 10:21pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/8 "2024-03-08T22:21:36Z")
> [@texases](#): > > t might be more productive to revive the old thread instead of starting a new one. Two different questions, not the same topic. ---
**Author:** ![weekend-warrior](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/weekend-warrior/32/26122_2.png) [@weekend-warrior](https://community.cartalk.com/u/weekend-warrior)\ **Post date:** [March 8, 2024, 10:21pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/9 "2024-03-08T22:21:54Z")
Just curious, are you sure it is evaporating and not draining slowly back to the tank? a gas cap going bad can cause flow back. If you have a separate in-line gas filter see if that is empty too. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [March 8, 2024, 10:25pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/10 "2024-03-08T22:25:11Z")
The carb float bowl is porous and leaking. Tester ---
**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\ **Post date:** [March 8, 2024, 10:29pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/11 "2024-03-08T22:29:21Z")
I would check to see if it is leaking out the bottom due to a plug that needs resealing or A crack in the housing. This would happen with my 59 Pontiac. Never found a solution except rapidly pumping the gas. Sold it about 1971 so memory is foggy. Tried dumping a little gas in the carb once, backfired and started a fire so not recommended. I’m sure the apartment got dinged for an empty extinguisher. ---
**Author:** ![It\_s-Me](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/it_s-me/32/12660_2.png) [@It\_s-Me](https://community.cartalk.com/u/It_s-Me)\ **Post date:** [March 8, 2024, 10:30pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/12 "2024-03-08T22:30:06Z")
> [@70's Ford truck carb problem](https://community.cartalk.com/t/70s-ford-truck-carb-problem/180434/1): > > After sitting 48 hours most of the gasoline in the fuel bowl has disappeared, > [@George\_San\_Jose1](#): > > unused for 5-7 days the fuel in the fuel bowl is presumably evaporating and doesn’t have enough fuel remaining > [@George\_San\_Jose1](#): > > not the same topic. Fuel bowl empty vs fuel bowl empty Yep, totally different ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 10:33pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/13 "2024-03-08T22:33:52Z")
> [@weekend-warrior](#): > > Just curious, are you sure it is evaporating and not draining slowly back to the tank? I don’t think it is possible for fuel in the fuel bowl to drain back to the tank via the carb’s inlet, it would have to go uphill. ---
**Author:** ![asemaster](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@asemaster](https://community.cartalk.com/u/asemaster)\ **Post date:** [March 8, 2024, 10:40pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/14 "2024-03-08T22:40:49Z")
> [@George\_San\_Jose1](#): > > Even simpler if there was a manual fuel pump available for this, using a rubber bulb I’d press a few times to prime the carb? How is that simpler, easier, or faster than just cranking the engine for an additional 5 seconds? ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 10:41pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/15 "2024-03-08T22:41:09Z")
> [@It\_s-Me](#): > > Fuel bowl empty vs fuel bowl empty > Yep, totally different Well, they do sound the same … lol . but if you read the 2021 OP, the clue was the throttle plates were covered with fuel. Not the case for the today’s question, throttle plates dry. & Last summer I removed the carb for another reason, and while it was removed, as a leak test, I filled the fuel bowl and placed the carb over a container over-night to see if any fuel was leaking out. None. The explanation for the empty fuel bowl seems like it pretty much has to be evaporation… ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 10:43pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/16 "2024-03-08T22:43:52Z")
> [@asemaster](#): > > How is that simpler, easier, or faster than just cranking the engine for an additional 5 seconds? I concur it is simple enough just to crank the engine longer. But it is more than 5 seconds longer. The downside of longer cranking is it runs down the battery, overheats the starter motor. ---
**Author:** ![pleasedodgevan2](https://avatars.discourse-cdn.com/v4/letter/p/ad7895/32.png) [@pleasedodgevan2](https://community.cartalk.com/u/pleasedodgevan2)\ **Post date:** [March 8, 2024, 10:44pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/17 "2024-03-08T22:44:22Z")
Usually the accelerator pump diaphram gets old and cracks, draining the fuel. If you try to start it after one day and it’s empty then that could be the problem. I had to replace that thing twice in seven years. Tomco kit. ---
**Author:** ![It\_s-Me](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/it_s-me/32/12660_2.png) [@It\_s-Me](https://community.cartalk.com/u/It_s-Me)\ **Post date:** [March 8, 2024, 10:45pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/18 "2024-03-08T22:45:31Z")
> [@George\_San\_Jose1](#): > > but if you read the 2021 OP, the clue was the throttle plates were covered with fuel. Not the case for the today’s question, throttle plates dry. 2 days vs 7 days, that’s 5 more days for evaporation. ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [March 8, 2024, 10:46pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/19 "2024-03-08T22:46:44Z")
Install one of these back at the tank: > **[Fuel Pump Carter P4600HP | eBay](https://www.ebay.com/itm/265753929045?epid=0&itmmeta=01HRG3W5GWV8WTR7J6W5JS7WBH&hash=item3de02b2555:g:1yAAAOSwJkBitM~v&itmprp=enc%3AAQAIAAAAwJvZUUReLiEDPf9ooHxsDlrLfmROLZJ6QFzyK%2Bn1FnPek40rpUPno3Bw9LlVZ1pizuQ5gMyfkAChMq48SYMIgwBAyGlxiYVIISA2REKRjMETYMCINy7JOTvV9X6I%2B8uGDugtg4NhnJk5P3jIYobgQjYCZzzXye64ZOPFr1ZGObjJL9%2FeK1qaW2AHGD2lAB4H07O1o5JXS0AS5FCA4cY5KIKqI4Yizb3Ioi2G3hHdpnm0IltwqPYX64dWfH--eyJBBA%3D%3D%7Ctkp%3ABlBMUNLY8IPEYw)** > > Part Number: P4600HP. Warranty Duration:No Warranty. People that look up auto parts for a living get paid to do it because it is not as easy as people might think. Auto Parts USA has over 40 years of auto parts experience. This is what old car restorer’s do to eliminate this problem and vapor lock ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [March 8, 2024, 10:47pm UTC](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506/20 "2024-03-08T22:47:21Z")
Now we’re getting somewhere! Thanks! [Next page](https://community.cartalk.com/t/carbs-fuel-bowl-losing-fuel-evaporating/194506.md?page=2)