Slee Cat Guards

[bloc]

IMO much, if not most, of the thermal energy being added to the fuel is from the fuel rails being tucked in close to the engine trapped under the hood.

My late summer experiment with measuring fuel supply/return temps didn’t work out because I was barely on trail for that trip. I plan to continue that this year.

 

[use2bn83]

I respectfully disagree.

When it's possible to boil gas on a rig without skids, even minor changes on a well designed skid will exascerbate the issue.

This has been a problem on the 100-series too. Land Cruiser tend to tuck their drivetrain and gas tanks higher up in the frame with less airflow to manage the trapped heat that then convectively heats the gas tank / fuel. Measuring ambient temp underneath doesn't tell the whole story as there's radiant heat that now bounces off the cat gaurd/skid that surely will impact the fuel tank.

Neither are necessarily to blame, but when combined, can cross the threshold where it's a bigger problem. Hopefully there will be a thread soon that helps point out where we can add heat shield to minimize the issue.

That’s fine. When I designed the slee skids, we did about 30hrs of temp testing with 10 temp probe locations. We then modified the design until there was no more than 20 degrees F difference from stock to Slee skids. We also tested ARB skids. My opinion, based on that testing, is that the small addition heat buildup with the additional sheet metal wings on the slee skids would be insignificant.

Edit: I should probably add that I no longer work at Slee, but the amount of thought and testing done to prove out products is pretty outstanding for a small company. Still good friends with the gang. Also, it was 10 locations not 8 haha.

 

[LCH21]

Since the addition of my Slee skids, I have not noticed the temp gauge being any different - sitting just below 1/2 and never moving - for what that is worth, which is probably not much.

Besides, that is a lot of ventilation:

 

[Docwyte]

My 200 came with ARB skids but I wish I had the Slee ones....

 

[use2bn83]

My 200 came with ARB skids but I wish I had the Slee ones....

Bang for the buck, the arb skids are a wonderful value. As mentioned before, the rear tcase skid is the one to keep off the rocks. Heck, the factory skids are decent enough for a lot of folks.

 

[04UZJ100]

Since the addition of my Slee skids, I have not noticed the temp gauge being any different - sitting just below 1/2 and never moving - for what that is worth, which is probably not much.

Besides, that is a lot of ventilation:

View attachment 3249231

The concern is not engine cooling, it’s heat soak in the fuel system causing fuel to boil in the tank.

 

[LCH21]

The concern is not engine cooling, it’s heat soak in the fuel system causing fuel to boil in the tank.

With all the 200 series LCs with all kinds of skids running around the desert southwest, I have never heard of this being a problem.

 

[04UZJ100]

With all the 200 series LCs with all kinds of skids running around the desert southwest, I have never heard of this being a problem.

Bruh - That’s because it doesnt happen in the desert.

It happens in high altitudes where the atmospheric pressure becomes lower than the vapor pressure of the gas. I have been on these forums for nearly 15 years. It happens to the 100 and the 200 and is documented on both forums.

 

[LCH21]

Bruh - That’s because it doesnt happen in the desert.

It happens in high altitudes where the atmospheric pressure becomes lower than the vapor pressure of the gas. I have been on these forums for nearly 15 years. It happens to the 100 and the 200 and is documented on both forums.

I have been in the desert at elevations of 7000 feet in 100+ temperatures. Over the last 40 plus years, I have been off-roading in everything from Jeeps to Unimogs at elevations from - 280 to + 13,000 and have never seen vapor lock as a problem. Not with me or any of the people I have been with.

 

[04UZJ100]

I have been in the desert at elevations of 7000 feet in 100+ temperatures. Over the last 40 plus years, I have been off-roading in everything from Jeeps to Unimogs at elevations from - 280 to + 13,000 and have never seen vapor lock as a problem. Not with me or any of the people I have been with.

Cool: you’re still wrong.

Gas tank building excessive pressure & fuel smell. Dangerous for sure! Why does this happen?

That's one constituent of gasoline, but there's a whole slew of other compounds that move boiling point all over the map for the mixture. Octane is about 250F, by itself, apparently, but I think the effective boiling point/range of all different grades and octane ratings really does span that...

forum.ih8mud.com

Gas/Fuel vapors/fumes visible from gas door

forum.ih8mud.com

 

[LCH21]

Cool: you’re still wrong.

Gas tank building excessive pressure & fuel smell. Dangerous for sure! Why does this happen?

That's one constituent of gasoline, but there's a whole slew of other compounds that move boiling point all over the map for the mixture. Octane is about 250F, by itself, apparently, but I think the effective boiling point/range of all different grades and octane ratings really does span that...

forum.ih8mud.com

Gas/Fuel vapors/fumes visible from gas door

forum.ih8mud.com

The RVP for gas is 7.8 psi. You have to be at 16,000 plus feet for this. Kind of hard to do in North America.

Please do not tell me what my offroading experiences are, you have not the slightest clue.

I am done mincing words with you.

 

[04UZJ100]

The RVP for gas is 7.8 psi. You have to be at 16,000 plus feet for this. Kind of hard to do in North America.

Please do not tell me what my offroading experiences are, you have not the slightest clue.

I am done mincing words with you.

I am not debating your off-roading boondoggles LOL

7.8psi at what temperature? It’s not constant. Thermal expansion of hydrocarbons is incredibly impressive. Stop trying to prove something you’re not technically competent in. The fact that you thought skid plates would affect the needle on your engine temperature gauges proves enough…..you have no idea what you’re talking about.

 

[Romer]

The RVP for gas is 7.8 psi. You have to be at 16,000 plus feet for this. Kind of hard to do in North America.

Please do not tell me what my offroading experiences are, you have not the slightest clue.

I am done mincing words with you.

I am not debating your off-roading boondoggles LOL

7.8psi at what temperature? It’s not constant. Thermal expansion of hydrocarbons is incredibly impressive. Stop trying to prove something you’re not technically competent in. The fact that you thought skid plates would affect the needle on your engine temperature gauges proves enough…..you have no idea what you’re talking about.

lets not get into a pissing contest

The fuel will boil with or without skid plates. It is a fact that has happened in my 80, 100 and 200 series. It has also happened to many I have wheeled with

It is a combination of factors. Ethanol Gas, High Altitude, Temp, How full the tank is and how long you have been driving building up pressure and temp in the tank

Everyone has a different experience base. Some may have never experienced it and some may have it all the time.

It is a real thing and although happens infrequently on the 200, it has happened at least once. Many time you won't notice it. You can tell if you smell fuel and/or if you open the fuel cap and hear it gurgling. Unless you detect the smell or gurgling sound, you typically wont even know it is happening.

 

[04UZJ100]

lets not get into a pissing contest

The fuel will boil with or without skid plates. It is a fact that has happened in my 80, 100 and 200 series. It has also happened to many I have wheeled with

It is a combination of factors. Ethanol Gas, High Altitude, Temp, How full the tank is and how long you have been driving building up pressure and temp in the tank

Everyone has a different experience base. Some may have never experienced it and some may have it all the time.

It is a real thing and although happens infrequently on the 200, it has happened at least once. Many time you won't notice it. You can tell if you smell fuel and/or if you open the fuel cap and hear it gurgling. Unless you detect the smell or gurgling sound, you typically wont even know it is happening.

Agreed. The individual was stating emphatically that it doesn’t happen.

 

[bloc]

Just to add one specific point: no one is saying Vapor lock is the problem for us. But boiling gas is, with eventual failure of the evap canister and at least on a 200 this can lock you out of 4-low. Totally beside the safety issue of hot gasoline crawling out of the tank fill and running down the side of the vehicle.

This is definitely an issue with so far no great solutions.. IMO a fuel cooler for the line running back to the tank is a decent idea.. but comes with its own drawbacks.

Either way with regard to the slee cat guards, my gut is they won’t hurt fuel temps, not much anyway. Seems like enough ventilation.. but this is far from scientific.

 

[AnyMal]

For anyone interested in running these on a ‘16+ LX, aka blacksheep, please see the photos attached for the required modification around the e-park brake components from my build. It was a very straightforward cut, NPI.

I corrected that little goof at the point ^

Going to come in handy in the wicked streets of H-Town.

 

[bloc]

For anyone interested in running these on a ‘16+ LX, aka blacksheep, please see the photos attached for the required modification around the e-park brake components from my build. It was a very straightforward cut, NPI.

View attachment 3279004View attachment 3279005
I corrected that little goof at the point ^
View attachment 3279006

Going to come in handy in the wicked streets of H-Town.

Their positioning for the electric parking brake mechanism is interesting to me, but I guess there aren’t a lot of options with the AHC stuff scattered everywhere.