|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
02-06-2019, 11:12 AM | #1 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Is fuel bubbling normal
I have a 31 Tudor. I notice that the fuel in the little plastic fuel filter I have on it seems to bubble as if boiling when I shut the engine off after driving. The carb is pretty warm but does not seem excessively so. Is this normal or does it indicate a problem?
|
02-06-2019, 11:30 AM | #2 |
Senior Member
Join Date: Jul 2018
Location: Spring Grove, Illinois
Posts: 1,371
|
Re: Is fuel bubbling normal
I would say that it is probably boiling. I can't really think of any other reason why it would be. Do you use any additives in your fuel?
|
Sponsored Links (Register now to hide all advertisements) |
|
02-06-2019, 11:33 AM | #3 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
No additives. Should I be?
|
02-06-2019, 11:38 AM | #4 |
Senior Member
Join Date: Jul 2018
Location: Spring Grove, Illinois
Posts: 1,371
|
Re: Is fuel bubbling normal
|
02-06-2019, 01:01 PM | #5 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
I use regular gas.
|
02-06-2019, 01:07 PM | #6 |
Senior Member
Join Date: Feb 2011
Location: Lincoln, Nebraska
Posts: 1,909
|
Re: Is fuel bubbling normal
Sponsored Links (Register now to hide all advertisements)
__________________
Dave / Lincoln Nebraska |
02-06-2019, 01:12 PM | #7 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
Tank has been cleaned and treated. Not sure if I have a pencil filter. Don't recall seeing one.
|
02-06-2019, 01:16 PM | #8 |
Senior Member
Join Date: Oct 2017
Location: Leicester, MA
Posts: 296
|
Re: Is fuel bubbling normal
How long does it do it?
If you have a pin hole as it cools it might suck air in. |
02-06-2019, 01:16 PM | #9 |
Senior Member
Join Date: May 2010
Posts: 433
|
Re: Is fuel bubbling normal
If the filter is a long way from the carb, I can't see how it's boiling. Even if it's close, I would guess it's simply air bubbles as the fuel drains a bit down to the carb as it's shut off. Check its temp with your hand or a cheap infrared temp indicator from Harbor Freight. They're super handy. I just googled boiling temp of gasoline and it's 203 degrees F.
I have clear fuel lines on a '53 Ford flathead and I see a surprising amount of bubbles. If you don't have symptoms of fuel starvation (sputtering and missing at high speed), I'd say you're fine. Good luck |
02-06-2019, 01:17 PM | #10 |
Senior Member
Join Date: Jul 2010
Location: Pennsylvania
Posts: 1,100
|
Re: Is fuel bubbling normal
IMO, the sediment bowl that is already in the system is enough to deal with what you'll experience with a clean and sealed tank. Adding an inline filter will just impede fuel flow in a gravity fed system.
|
02-06-2019, 01:17 PM | #11 |
Senior Member
Join Date: Aug 2011
Location: Eagle Bend, MN
Posts: 2,025
|
Re: Is fuel bubbling normal
If you are getting excessive heat, yes gas will boil at somewhere around 200+ degrees F, depends on the blend. If the timing is incorrect, then there will be excessive heat. If all is running fine, just some boiling in the line at shutoff, it won't hurt anything. If its really a hot day 200 degree engine bay in ok.
__________________
"There are some that can destroy an anvil with a teaspoon and shouldn't be allowed to touch anything resembling a tool." |
02-06-2019, 01:24 PM | #12 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
It stops when I shut the tank valve off. Sorry I did not think about it until just now
|
02-06-2019, 01:29 PM | #13 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
Thermometer would be handy. Getting one next time.
|
02-06-2019, 02:12 PM | #14 |
Senior Member
Join Date: May 2010
Location: Bismarck ND
Posts: 1,189
|
Re: Is fuel bubbling normal
The initial BP of gasoline is about 95 degrees F. it is a mixture and the final BP is about 200F
|
02-06-2019, 06:31 PM | #15 |
Senior Member
Join Date: May 2010
Location: Stuart Florida
Posts: 148
|
Re: Is fuel bubbling normal
Plastic fuel filter. Sounds like a fire hazard to me. Should be a steel fuel line. No rubber no plastic.
|
02-06-2019, 08:29 PM | #16 |
Senior Member
Join Date: May 2010
Location: on the Littlefield
Posts: 6,159
|
Re: Is fuel bubbling normal
If you use the cast iron sediment bowl, and steel pipes you never have worries about fuel bubbling
|
02-07-2019, 08:15 AM | #17 |
Senior Member
Join Date: Oct 2018
Location: Glendive MT
Posts: 155
|
Re: Is fuel bubbling normal
If you are using an ethanol blend, ethanol has a much lower boiling point. Something like 147*.
|
02-07-2019, 08:24 AM | #18 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
Only fuel available here is 10% ethanol.
|
02-07-2019, 08:26 AM | #19 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
Plastic filter is far from the manifolds but I'm probably going to get rid of it as I'm sure it is a weak link in the system.
|
02-07-2019, 08:30 AM | #20 |
Member
Join Date: May 2011
Location: Dallas, TX
Posts: 53
|
Re: Is fuel bubbling normal
Thanks to all who replied. weather has turned bad here so I won't be taking it out for a while but I did buy the infrared thermometer and that should tell the tale if the engine is over heating. This car is an ongoing project and I'm glad you guys are here to ask for help.
|
|
|
Sponsored Links (Register now to hide all advertisements) |
|