100 Caught fire & gas tank venting concerns (2 Viewers)

[Skidoo]

[Edited 9/20/2018]
The post I linked to here in "What have you done to your 100" has been removed.
That post had more info, so I will fill in a little bit here.

I originally found out about this on Facebook where a person present, wrote up the event and posted photos of it occurring. That posting was taken down a day after it was posted.
It is not clear how the fire started, but hearing from the folks that were there, it escalated quickly to totally burn the entire vehicle. From the photos it looked like it started under the car near the rear wheels.
This incident was at Cerro Gordo, CA, elevation 9000ft, mid 70s temperature.
There was some mention of it having a previous fuel system issue, which may have not been resolved fully. It has been a year since this occurred and no new information has surfaced, we don't have enough info to say what caused the fire.


We may want to discuss fuel tank venting, as owner was venting his tank about time fire started, but it may not be the cause. Those of us that have taken our 100s to high elevations have encountered the gas smell as it seems venting has trouble keeping up with elevation change. At 100s in the Hills (its all above 9000 ft) we are told not to fill tank all the way to mitigate the issue. A number of folk there needed to vented their tanks and saw the amount of pressure build up, some with enough pressure to blow some fuel out. Venting in these cases needs to be done slowly and carefully.



[The following added 8/25/2018]

More data on this issue. Ethanol smoking gun?? I just spent a week in Silverton, CO running the high passes. Last year a week earlier I was in Silverton for 100s in the Hills. Weather conditions were the same as last year, and ran the same trails this year. This area has to be the worst case scenario for gas tank venting as Silverton is 9300 feet in elevation and you are going up to passes as high as 13,113 feet from there.

Last year I ran gas with ethanol and had high pressure venting when opening cap at the passes. Only filling to ¾ of a tank helped but did not eliminate the pressure venting. This issue seemed to be common with the other rigs on the trail.

This year 100s in the Hills was too early for me to attend, so planned my own trip with a friend and his 80 series. This year we found a small station in town that offered ethanol free premium gas and we used only that for both our rigs. I had no venting pressure at all when opening gas cap on the high passes this year. After the second day I was filling the tank to full and no issues. My 100 is the same, no changes since last year. My friend’s 80 has had the venting issue in the past but running ethanol free gas here he also had no venting pressure when opening gas cap on high passes.

My belief is that its the ethanol based fuels causing this issue, but run your own tests, see what you find.
I see the labels on gas pumps say "May contain up to 10% ethanol" wonder how much ethanol content actually varies station to station and over seasons. This might explain why folks see different behavior.

 

[collk22]

Giving this its own thread as it is in What have you done to your 100. Link to it here
What have you done to your 100 Series this week?

Those of us that have taken our 100s to high elevation have encountered the gas smell as it seems venting has trouble with elevation change. At 100s in the Hills (its all above 9000 ft) we are told not to fill tank all the way to mitigate the issue. A number of folk have vented their tanks and seen the pressure build up. Venting in these cases needs to be done slowly and carefully.

The incident above was at Cerro Gordo, CA, elevation 9000ft, mid 70s temperature. May have been due to venting, or some other condition.

Is venting the best way to alleviate this issue? Any guidelines or procedures on how to properly and safely vent a 100-series when this issue occurs?

 

[ttFJC]

This is interesting. I never thought about that being a problem. learn something everyday. i don't drive a 100 but i think it would apply to Toyota of similar years. I drive a FJC.

 

[a_traut_man]

The sound of venting was pretty normal for me when we were living in SW Colorado (~5,700') but I have even heard it on a somewhat regular basis since getting to Texas. Can't see it accumulating around the fuel door the way you can up high but it is still there and never had it to the point that liquid fuel was blowing out of the tank (just vapor).

Anyone know of any kind of fuel tank breather issues or options for the 100? Scary deal for sure, glad everyone was alright.

 

[geanes]

The vapor scares me more. Seems like any spark within 20 feet of the truck will send it up in flames. Guess it's important to have a good gascap for sure. Very curious if there is any way to vent off the pressure gradually as you're increasing in elevation so you don't have a catastrophic blowout. My tank boiled like crazy at the top of Imogene and Mosquito (both well over 13k). It was loud enough that other people walking nearby asking what the sound was. I didn't hear any of the other vehicles up there boiling....at least, not as loud as my 98 LX.

 

[jdayment]

Is it related with the Charcoal Canister like it is with the 80 series? I hear a faint vent here in AZ when filling of the 100 but never experienced the leve of what some describe it even when at over 6000 ft when we lived in NC

 

[4Beast]

Would be nice to get more info re: venting and prior fuel issues, doesn't seem that it was normal, even for the venting issue, if they could smell fuel 500' away beforehand...

 

[suprarx7nut]

Good reminder to get a fire extinguisher (or three) mounted up in the 100...

Scary stuff. Yikes. I'd like to learn more about that specific car and what was known beforehand.

 

[470SNC]

The crazy thing is that they were saying they had three fire extinguishers with them, and they could do nothing to stop the flames due to being fuel related. I have heard people to vent the gas cap by opening slowly to alleviate the pressure. It's the first time for me hearing this about the 100 series and its quite scary. They say its due to the charcoal canister getting saturated over the years to where its no longer operable. Maybe time to go replace the charcoal canister prematurely.

 

[Trunk Monkey]

Before we start a wild goose chase on charcoal canisters and fire extinguishers I think it bears note that the OP said there was potentially a known issue with the fuel system. Until we know the full story it's all speculation.

 

[Skidoo]

There are too many unknowns in this event to determine cause, and due to condition of vehicle now, doubt we will find out.

That being said we should take precautions with our vehicles on trips to high elevations.
Lets address fuel tank venting which we know is an issue. We can speculate as to why venting is an issue and a potential reason is ethanol in fuel. Fuel with ethanol releases more total vapor than fuel without ethanol. The evaporative recovery systems in older vehicles were designed without ethanol in mind and so can be overloaded in some cases. Some things that cause more vapor generation are fuel sloshing around from turns and rough roads, and lower atmosphere pressure at high elevations.
So offroading at high elevations (9000ft +) is probably most folks worst case situation. You will probably not see this issue in most driving conditions.

For high elevation trips a precaution is to not fill tank all the way, only 3/4 to 7/8 full, gives more space for vapor.
Here is what I have come up with for safely venting.
1. No nearby flames
2. If you have been riding brakes may want to let them cool a bit
3. Crack open gas cap just enough to let it slowly vent, you don't want to create a large cloud of vapor

 

[kevine]

I know who the owner of the vehicle is and have personally spoken to those with him who are friends of mine and were actually there. It is my understanding he may have had a venting issue. However, again, I've been told this by at least two who have personal knowledge. He had a prior fuel issue. He did a very challenging run previously, got winched several times which caused damage to the underside and a fuel leak. This was a different run, either weeks or months before this fire occurred. It was a different/prior trip.

On this trip, where the fire occurred, it is unclear if he had any repair done, or if the leak stopped so he just didn't have anything done. I've been told that a mechanic looked at it and told him it was a "vent valve that was stuck." So the owner just continued to drive it. On this occasion, the odor of fuel was present and when he stopped at CG, the fire occurred. Where the fuel leaked from, what it came into contact with to start the fire, etc. I don't know. Don't want to speculate any more than I may have but again, I've spoken to people who were on the first trip that caused a fuel leak, and on the trip where the fire occurred.

Lesson learned, make sure your s*** is in order before going on a trip and if you believe a friend's rig is not ready, be the bigger person and tell him or her to stay home.

 

[2000UZJ]

I had my gap cap blow off going up Pikes Peak. I reached the top and the truck smelled like fuel. I slowly backed the cap off and boom she went, no fire but it bruised my shoulder and went about 20 feet. My truck had never been in high altitude pressures. It was a sea level rig for 13 years before seeing anything over 4,000ASL.

No evap work, no fuel tank work.

 

[Skidoo]

Do you know what year 100 it was?

I know who the owner of the vehicle is and have personally spoken to those with him who are friends of mine and were actually there. It is my understanding he may have had a venting issue. However, again, I've been told this by at least two who have personal knowledge. He had a prior fuel issue. He did a very challenging run previously, got winched several times which caused damage to the underside and a fuel leak. This was a different run, either weeks or months before this fire occurred. It was a different/prior trip.
...

 

[PabloCruise]

Terrible loss. I am glad no one got hurt, especially glad it was not parked in someone's garage when it lit off...

 

[RyanStl]

I would love to know more about the particular truck involved. The owner probably won't talk due to insurance.

 

[Julian Stead]

Can't you just remove your fuel cap if you know you going to be at a high altitude , or adapt a spare cap so it allows the tank to breath easy, who cares about the emmisions or CEL. I am sure if they can put fuel into aeroplanes, then there must be a easy solution. Just try and open vent the tank somehow. Then put it back once you drop back down to a lower elevation. I have never worked on a system with a charcoal Canister, the manufacturer I worked for just vented it into the intake via a solenoid valve.

 

[1meancruiser]

I had a similar issue a few months back at higher elevations and over 100° temperatures, it resulted in the hissing from the gas tank as well as the fuel boiling over. My mechanic knows Toyotas well, we replaced the fuel pump which Had overheated,We Replaced the charcoal canister per the toyota service service bulletin as well as the vent valve which is inside the tank. It required him to drop the tank in order to access it. My cost was approximately $1700, not fun but I think and I hope that this issue is resolved.

It never through a code but the Charcoal canister was saturated with Fuel When my mechanic Took It out. I hope this helps.

 

[abuck99]

Really sad to see someones vehicle burn to the ground. It’s a helpless situation once it gets going, theres nothing that can be done but sit and watch. Glad to know no one was injured.

I would not remove the gas cap. Let the evap system manage the excess pressure.

Fwiw excess fuel vapor pressure is not limited to high altitude. On a few occasions here in GA Ive had some excessive tank pressure and heard a shuttering sound at the fuel cap as the pressure was being vented through the cap- this was in 90 + degree temps. I could see a plume of vapor off gassing from the truck and definitely smelled it from 20ft away. Definitely not safe. The cap is new and we’re only at 1,000 feet elevation here.

 

[Skidoo]

...
I am sure if they can put fuel into aeroplanes, then there must be a easy solution. Just try and open vent the tank somehow. Then put it back once you drop back down to a lower elevation. I have never worked on a system with a charcoal Canister, the manufacturer I worked for just vented it into the intake via a solenoid valve.

Airplane fuel tanks are pressurized by their vent systems to prevent fuel evaporation at altitude.

Think there is a CEL code if you leave gas cap off, wonder how bad it would be.

Evaporative emissions control systems purge the fuel vapor from the charcoal canister to intake manifold, but don't know Cruiser parameters. Typical systems don't purge when vehicle is stopped, could be you need to be in motion and exceed some rpm.