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MDH33
07-14-2013, 07:33 AM
I was wondering if anyone has an idea what would cause my 60 to barf fuel out the filler tube?

I parked at a trailhead for 4 days with 3/4's of a tank. It was at a tiny bit of an angle tilted to the passenger side. I could smell gas when I parked, but didn't think much of it since it's a 2F. When I hiked out after 4 days, I found the huge puddle of fuel and realized that gas had been trickling out the filler past the gas cap. Lost 1/4 tank and a lot of paint. :(

I could see this happening if I had a bad gas cap, parked on a huge angle and had a full tank, but that was not the case. I am wondering if there is some sort of pressure issue that forced it out?

treerootCO
07-14-2013, 12:40 PM
10% Ethanol fuel boils at altitude. The next time you are out, pull the cap and listen to the fuel tank. It will literally be a rolling boil....

treerootCO
07-14-2013, 01:07 PM
Remember your backpacking days when you discovered boiling water at high altitudes isn't hot.

Methods used at high altitudes

From pressure cooking: A pressure cooker is often used to compensate for the low atmospheric pressure at a very high elevation. Under these circumstances water boils at temperatures significantly below 100 C (212 F) and, without the use of a pressure cooker, may leave boiled foods undercooked, as described in Charles Darwin's The Voyage of the Beagle (chapter XV, March 21st, 1835 books.google):


There are lots of articles... get ready for when 25% makes our old iron obsolete. Conspiracy or not, it will take some getting used to. Also remember that current emissions regulation does everything in it's power to prevent your gas tank from venting into the atmosphere (non vented gas caps and charcoal canisters) that makes the problem worse.

I'll get off my soap box if you ask me to :) Try to buy an LED or CFL, for your oven or dryer, now that we decided incandescent light bulbs are bad...

I learned this today reading the article below... E10 fuel is not as stable as past formulas. Older formulations would stay €œfresh€ for about 6 months. E10 can go stale in about 2 €“ 3 weeks.

Here is one on boats... I found a few articles that farmers had written that their old tractors cannot run on 10% ethanol and their tanks are boiling...
http://www.stripersonline.com/t/509267/interesting-read-on-ethanol-fuel-problems

I received this article in a email from Marine Parts Express.com they sell & service marine engines and parts. Hope it helps you guys with your fuel problems.





ETHANOL PROBLEMS





By Robert Van Brunt


Chief Petty Officer U.S.G.G. ret





ETHANOL AND VAPOR LOCK





Short description:


When the engine compartment becomes hot either by climate or idling, and you use ethanol-blend gasoline it can cause excessive vapors in your fuel line and starve the engine of fuel. The engine can run poorly or stop and will not run until the fuel condenses.





THE PROBLEMS





Vapor Lock





Fuel containing 10% ethanol is called E10. If you have ethanol in your gas, you run the risk of creating vapor lock because of excess vapors.





Ethanol €œboils€ at 87ºF (at normal atmospheric pressure) and turns from a liquid to a gaseous state. By comparison, most automobiles have their fuel pump in the gas tank, so the whole system remains under pressure unlike boats whose fuel tanks are vented. In a closed system, the higher pressure raises the flash point of the ethanol reducing the amount of vapor that is produced. In addition, most automobile fuel lines are outside of the vehicle allowing them to stay cooler.





Since most boat fuel lines are in the enclosed space (sometimes even insulated) of the engine compartment, normal ventilation will not cool the fuel significantly enough to avoid the potential problems of vapor lock. Furthermore, since the fuel pump in a boat is mounted on the engine (versus a car where the pump resides in the tank) the action of the pump can reduce pressure in the tank to below atmospheric pressure and further reduce the flash point.





Boat engineers are aware of this problem and are reducing the likelihood of this occurring by reducing the suction required by the fuel pump, minimizing hose fittings and bends, and including a quality anti-siphon valve. In existing boats, fuel lines and filters should be kept as low in the boat as possible and tank vents should be cleaned and open.





Heat Soak





Most boats have €œforced€ ventilation. Air moves through the engine compartment when the boat moves forward. Heat soak happens after you have been at high RPM and then stop or drift on idle for a while. Because of heat soak the engine compartment will rise to a point where the ethanol will boil





THE CURE





To prevent vapor lock (i.e. boiling ethanol):





1. Make sure the engine compartment has adequate ventilation.


2. Relocate fuel lines to be low in the bilge. (The bilge is cooler because it is in direct contact with the water.)


3. Monitor the engine compartment temperature.


4. Add (or turn on) engine room blowers.


5. Keep the tank vent clean and unobstructed.

rover67
07-14-2013, 11:49 PM
yeah the vent system on the 60's can't keep up with hot e10 fuel i think. mine will do something similar.

Make sure the cap can hold decent pressure and go through a quick check on the evap system including the charcoal canister checks.

Rzeppa
07-15-2013, 10:16 AM
Been having vapor lock issues in my 40 on Spring Creek for a while now, even with a new fuel pump. Been opening the hood when stopped and waiting for other rigs to make it over obstacles.

SteveH
07-15-2013, 10:54 AM
I have heard of folks putting some quantity of 2 cycle oil in their E-10 (in old/classic cars) to cut back on vapor locking. Sounds nutty, but I may try it. It certainly cannot hurt the engine. I'm thinking about 8 oz./half tank of an FJ40. If it makes no difference, then dump in another 8 oz. I suspect it won't help, but who knows.

PabloCruise
07-15-2013, 01:41 PM
Along the lines of Steve's idea...
When I got the 40 running back in 2002, I moved to about 7000 feet in New Mexico. Carb cooling fan was not working yet and I would get vapor lock. The guy that did the engine build said to add a quart of ATF to each tank to cut down the vapor lock. It seemed to help.

Rzeppa
07-15-2013, 06:49 PM
Either 2 stroke oil or ATF would generally increase the average molecular weight of the fuel and thus lower the vapor pressure of the mixture. As long as it didn't foul the plugs or cause undue deposits on the valves and stuff that seems like a decent idea.

MDH33
07-17-2013, 02:11 PM
I'm certain my 40 vapor lock issues are the fault of ethanol fuel, but the 60 forcing 1/4 tank out the filler doesn't make sense. If it was just the ethanol causing that then it seems every vehicle would do it.

rover67
07-17-2013, 03:59 PM
I'm certain my 40 vapor lock issues are the fault of ethanol fuel, but the 60 forcing 1/4 tank out the filler doesn't make sense. If it was just the ethanol causing that then it seems every vehicle would do it.

mine has done the exact same thing. in beef basin while we were hiking.

if the vehicle is tilted so the fuel level is over the fill pipe then excess pressure forces fuel up and out. In my situation my fuel cap was loose.

60wag
07-17-2013, 04:14 PM
Isn't there a second skinny tube parallel to the filler tube that connects to the filler tube near the gas cap? I thought that was a vent line to prevent fuel being pushed up the filler tube. Maybe the vent line is plugged up?

Both of my 60's would make continuous gurling noises from the fuel tank in warm weather. I went as far as replacing the charcol canister on one of them hoping to solve the problem but it didn't help.

My 80 has developed the stinky fuel smell of a saturated charcol canister. I need to look into replacing it. On a recent camping trip after parking the the truck, I noticed the fuel smell and decided to just vent the tank pressure and get the smell done with quickly. I loosened the cap and the pressure surged out of the tank but didn't stop as I expected. It kept going, I waited maybe 30 seconds and the flow continued so I resealed the cap and found something else to do. Maybe it was the combo of the altitude, the heat and the ethanol content that made the system evaporate so rapidly.

PabloCruise
07-18-2013, 02:27 PM
I'm certain my 40 vapor lock issues are the fault of ethanol fuel, but the 60 forcing 1/4 tank out the filler doesn't make sense. If it was just the ethanol causing that then it seems every vehicle would do it.

Yes, shouldn't the evaporative emissions system capture the vapors and route to the charcoal can?

PabloCruise
07-18-2013, 02:29 PM
Yes, shouldn't the evaporative emissions system capture the vapors and route to the charcoal can?

That can is open to the atmosphere on the bottom, so it should be able to continue to recieve vapors for as long as the tank has internal pressure (probably until the liquid cools off).

SteveH
07-18-2013, 03:17 PM
My 80 series would develop amazing in-tank pressures on a hot day. 30 seconds after you removed the cap, it was still hissing and spraying liquid fuel droplets out around the filler neck. I don't think that modern evap systems are truly vented to the atmosphere, even after all the charcoal cannister action. I'm convinced also that FJ55 gas tanks crack/rupture on the top due to pressure cycling - even back then.

MDH33
07-21-2013, 01:35 PM
I'm going to check the hoses and charcoal canister. Also found a couple of threads on MUD suggesting switching the tubes on the canister to create constant vent.

60wag
07-21-2013, 05:37 PM
The charcoal canister has a couple of check valves on it. The fuel vapor has to build enough pressure to push a check valve open before it can flow into the charcoal. The pressure required to open the valve is supposed to be pretty low but it exceeds what you can produce by blowing on it with your mouth. I think the valves get sticky over time and the cracking pressure can go up.

Jacket
07-22-2013, 05:25 PM
So if this check valve wasn't working properly, this would cause excessive pressure build up in the tank, and extended "hissing" when you remove the gas cap?

I stopped somewhere in Wyoming earlier this week (heat of the day and driving at 80 mph) to fill up the 80 and the hissing and bubbling went on for a minute or more - so much so that I couldn't get the gas pump to put fuel into the tank. The vapors and gurgling kept shutting off the pump.

farnhamstj
07-22-2013, 06:55 PM
I had this happen today!!! In my new 2013 Club-car kawasaki 350cc powered golf cart. I had just dropped off passengers. Super hot day 85 degrees at 8200ft. The fitting with the hose that goes from the tank to a charcoal canister, blew off and I had a fountain of fuel that was powerful enough to lift the golf cart seat. Gas was just bubbling, never seen anything like it before.

MDH33
07-24-2013, 09:35 AM
Makes me wonder if the gas stations are secretly feeding us the E25 already. :rolleyes:


I replaced a crappy aftermarket gas cap with an OEM unit. Seems to seal better. I noticed a big Whooosh of pressure when I opened it with the new cap. Definitely some excess pressure building in there.

FJBRADY
07-24-2013, 09:45 AM
I just got back from Ouray and near the top of Imogene we stopped and I thought I had a flat tire the hissing from the gas cap was so loud. Took the cap off and the hissing lasted for 20 or so seconds.

I blamed it on the altitude and sped off.

:)

rover67
07-24-2013, 10:06 AM
In Telluride I had to pull off of the road because the fuel pump was cavitating and the engine quit. I suspected excess pressure in the tank as the culprit due to a faulty evap system (this is before I realized it was the fuel boiling) so I unscrewed the gas cap. The pressure blew it out of my hand and a few feet away in the parking lot. The vapor coming out of the filler neck was ridiculous. It continued to come out so fast it scared me so i got the dogs out of the car and we sat down 50 feet away or so to let it do it's thing. I swear it didn't slow down for 10 minutes. eventually I replaced the cap and drove it to a gas station where topping off with cold fuel fixed it.

I think keeping the fuel system closed up where the pressure can build is really the only way it'll work at high altitude and high temperatures. Even though our older fuel systems were not designed to work like that.

http://www.tn.gov/agriculture/publications/ethanol/1_E10fuels.pdf

SteveH
07-24-2013, 10:11 AM
Thanks for the link to the Tennessee gov't report - it reminds me that my Toyota runs poorly due to gov't regs, and not the way it was engineered. I long for the days (15 years ago) when I could buy 100% gas and it would not vapor lock and hot-soak and misbehave.

PabloCruise
07-25-2013, 05:13 PM
I'm going to check the hoses and charcoal canister. Also found a couple of threads on MUD suggesting switching the tubes on the canister to create constant vent.

In the 80 section?

Rzeppa
07-25-2013, 05:48 PM
Thanks for the link to the Tennessee gov't report - it reminds me that my Toyota runs poorly due to gov't regs, and not the way it was engineered. I long for the days (15 years ago) when I could buy 100% gas and it would not vapor lock and hot-soak and misbehave.

X2 on that good buddy. Even when they used MTBE instead of EtOH. I 100% blame my stall on the steepest section of Radical Hill yesterday on the EtOH.

60wag
07-26-2013, 08:42 AM
What's odd though is that from 4% EtOH on up to 20%, the vapor pressure doesn't change much. So the change from 10% to 15% shouldn't make much difference other than the loss of energy density (lower mpg).

rover67
07-26-2013, 09:01 AM
What's odd though is that from 4% EtOH on up to 20%, the vapor pressure doesn't change much. So the change from 10% to 15% shouldn't make much difference other than the loss of energy density (lower mpg).

I also thought that was interesting. Makes sense too.

Higher EtOH % will eventually start to be more corrosive on fuel systems not designed for it though.

treerootCO
07-26-2013, 11:35 AM
My favorite is the Ducati lawsuit:
http://www.ducatinewstoday.com/2010/11/ducati-sued-over-faulty-gas-tanks/

As reported by the web site Ducati News, the lawsuit alledged that

"The plastic used in Plaintiff and class members’ fuel tanks is incompatible with the motorcycles’ fuel, which causes the tanks to rapidly degrade and deform and leads to a number of unsafe conditions. Among other things, as the plastic degrades and deforms, the fuel tanks interfere with the full range of steering, leak fuel onto the engine, and destabilize the motorcycle’s weight distribution – often to the point that the motorcycle cannot be safely operated after only a few thousand miles of use."

The tanks manufactured by Acerbis Plastics are also specified as original equipment in other European brand motorcycles such as Aprilia and KTM.

It is not clear what is causing the issue although there is speculation that small proportions of ethanol blended with gasoline in the United States may be the culprit.




I saw it in my small engines first. The hoses collapse and the little bits get stuck in the engine. If you let it go long enough, the hose falls apart.

Napa carries a new red hose that is rated for ethanol. The parts guy mentioned to me that Napa made the change to prevent being sued for fuel line failures.



Gates has a greenshield:
http://www.gates.com/brochure.cfm?brochure=12468&location_id=5348

I fast forwarded it to the Ethanol part:
http://youtu.be/jAg8lBJf1ZE?t=3m10s

GoodYear lists marine applications and hoses for E85 pumps:
http://www.goodyearep.com/search.aspx?q=ethanol

SteveH
07-26-2013, 12:13 PM
I've fixed a lot of lawn mowers that use un-rated fuel line - it's not even SAE 30R7 rated. It's typically brittle and full of cracks. Leave it to lawn mower makers to use a fuel hose that barely even qualifies as fuel hose.

To me, this stuff is a fire risk when the hose rots through after 5-10 years and fuel placed in the mower simply runs out on the ground.

Pep Boys sells 'R7' and 'R9' by the foot and the R9 is a lot more expensive, but it's diesel compliant and obviously better stuff for any gas application.

nakman
07-26-2013, 03:21 PM
That's funny you highlight KTM, Mike, as we're routinely dumping little black flecks out of the bottom of the carbs. I wonder if instead of adding stabilizer for the winter would I be better off just draining the tank and storing it empty for 3-4 months? or would it make much of a difference...

I'm going to look for a new fuel hose though, where do they sell that Gates stuff? cool video. :moto:

Rzeppa
07-26-2013, 05:25 PM
What's odd though is that from 4% EtOH on up to 20%, the vapor pressure doesn't change much. So the change from 10% to 15% shouldn't make much difference other than the loss of energy density (lower mpg).

Do you have a chart somewhere you could turn us on to? I would expect a linear change in vapor pressure as the EtOH concentration is increased. It's a pretty darn light little molecule compared to Heptane. FWIW, I run premium in my 60 since I had the head decked.

One other interesting tidbit. 60s recirculate the return back to the pump, so it all stays in the engine bay where it's hot. My 76 recirculates back to the tank where it should be a lot cooler.

MDH33
07-26-2013, 07:49 PM
Did you guys catch the bit in the PDF regarding the fuel separation in the tank and in the tanks at the filling stations? The ethanol sludge settles out at the bottom, so if the tank sits, you could be pumping nearly pure ethanol sludge into your tank. the tank I had put in when it boiled out of my filler was from a suspect station. I had noticed I couldn't hit normal speeds on that tank. I just filled up with gas from my regular station and it hasn't overflowed and I suddenly can hit normal speeds on the hills again.

60wag
07-26-2013, 09:48 PM
Maybe the "bad gas" frequency will go up with Ethanol settling to the bottom of storage tanks?

The vapor pressure values I got the from the Tennessee report that Marco linked above.

Doesn't the 60 fuel pump recirc back to the tank when the carb bowl valve shuts off?

Rzeppa
07-27-2013, 04:26 PM
Maybe the "bad gas" frequency will go up with Ethanol settling to the bottom of storage tanks?

The vapor pressure values I got the from the Tennessee report that Marco linked above.

Doesn't the 60 fuel pump recirc back to the tank when the carb bowl valve shuts off?

No, on a 60 it recirculates back to the inlet of the pump. My 1976 CA-spec FJ40 recirculates all the way back to the tank, which is more plumbing but keeps the fuel cooler. My 1971 FJ40 and my 1978 non-USA FJ45 do not have any returns, they just stop when the needle valve closes.

rover67
07-27-2013, 07:07 PM
Weird, my 60 recirculated back to the tank. In fact I use that same return line today still with the injected setup.

60wag
07-27-2013, 10:35 PM
Both of my 60s had a single fuel line between the pump and the carb while they had two lines between the tank and the pump. I always thought one was a supply line for the pump and the other was the return to the tank.

Rzeppa
07-28-2013, 06:41 PM
FJ60s have three ports on the fuel pump: inlet, outlet and return:

PabloCruise
07-29-2013, 06:34 AM
The charcoal canister has a couple of check valves on it. The fuel vapor has to build enough pressure to push a check valve open before it can flow into the charcoal. The pressure required to open the valve is supposed to be pretty low but it exceeds what you can produce by blowing on it with your mouth. I think the valves get sticky over time and the cracking pressure can go up.

I would check the FSM for a test procedure for those valves. My 40 manual just says you should be able to blow air into the tank port, as well as the purge port. Then it says you can clean the charcoal by capping off both of those and blowing air into the port that vents the carb float chamber into the can at 40 psi.
There are no pressure specs for testing the check valves.