Oil & Fuel Here's one for the Mahingra reps and Moderators

Mike in La. · Jun 30, 2011

This is gonna be long but please hear me out.....I have a 2006 6500FWD and when I need it to make a 10 hour day in 104 degree Texas heat, it won't and here's why: I work in a refinery and make diesel fuel. With the advent of our government mandating that we only make "ultra low sulphur diesel" (15 ppm sulfur max) the density and viscosity of the fuel is closer to that of naptha or gasoline.....not at all what we're used to running in our tractors. As the machine heats up with the fuel tank located where it is, the fuel gets too hot and thins (more heat = less viscosity) to the point that the injector pump will not put up the pressure to accomplish injection. The machine misses, loses power, and we all know what it's doing to the pump. I discovered this by checking for water at the filter drains the first time it happened and actually burned my hand with the hot fuel. Kubota and others got smart and moved their tanks. What will Mahindra do? Especially for the machines already out there with this design shortfall? I'll bet you're gonna sell lots of injector pumps. How about an insulation kit we can retrofit to our fuel tanks? Anyone else experiencing this after 8 hours in the 104 degree heat? Anyone have any ideas on an easy fix? I Love this tractor but am not about to buy a pump due to an engineering boo-boo. How bout it Mahindra guys, put your heads together and solve this.

sweettractors · Jun 30, 2011

Mike in La. said:
This is gonna be long but please hear me out.....I have a 2006 6500FWD and when I need it to make a 10 hour day in 104 degree Texas heat, it won't and here's why: I work in a refinery and make diesel fuel. With the advent of our government mandating that we only make "ultra low sulphur diesel" (15 ppm sulfur max) the density and viscosity of the fuel is closer to that of naptha or gasoline.....not at all what we're used to running in our tractors. As the machine heats up with the fuel tank located where it is, the fuel gets too hot and thins (more heat = less viscosity) to the point that the injector pump will not put up the pressure to accomplish injection. The machine misses, loses power, and we all know what it's doing to the pump. I discovered this by checking for water at the filter drains the first time it happened and actually burned my hand with the hot fuel. Kubota and others got smart and moved their tanks. What will Mahindra do? Especially for the machines already out there with this design shortfall? I'll bet you're gonna sell lots of injector pumps. How about an insulation kit we can retrofit to our fuel tanks? Anyone else experiencing this after 8 hours in the 104 degree heat? Anyone have any ideas on an easy fix? I Love this tractor but am not about to buy a pump due to an engineering boo-boo. How bout it Mahindra guys, put your heads together and solve this.

For summer use, Is there a additive you could put in the fuel or maybe change fuels brands? Ken Sweet

MarkV · Jun 30, 2011

That is interesting Mike. Something I never would have thought of but it sounds like you work someplace where you would learn that type of thing. My question would be why would you include the forums volunteer moderators in your title line? They surly have nothing to do with what you see as a Mahindra design issue.

MarkV

wallace · Jun 30, 2011

Would this be the same if I told you that up here in the northeast we need the fuel tanks under the hood so the heat from the engine will allow the fuel to keep flowing, due to the cold weather.
I guess this is just something that both of us have to deal with.
We run additives up here and you should be running them down there also.
It is not going to get any better as the emission restrictions are getting tighter in the future.
I do not see this as a design flaw but more a govt flaw.

tractorboy5500 · Jul 1, 2011

I dont have a 6500, but I do have 5500 4x4, which has the same pump and set up, I ran mind for a 3 to 3 1/2 day period cutting and rolling and bailing hay, I am running 100% of my pto hp when bailing hay. Anytime you are doing field work, need to keep the radiator screen clean, thats a problem with any tractor. But I have not had the problem you have had yet. And I did this about 3 weeks ago, and its been very hot in south east Texas.

You really need to check you radiator screen.

boomer1025 · Jul 1, 2011

Mount a fuel cooler in front of the radiator, you could possibly use an automatic transmission cooler.

Mike in La. · Jul 5, 2011

Thanks for the input guys........didn't mean to step on moderator toes, just thought they may possibly rattle one of the Mahindra guys chain. The fuel gets hot enough to actually burn your hand if you pull the filter drain plug. I've changed filters several times with the same result. And the entire tractor (radiator screen included) is always kept clean. After 8 hours or so the fuel is so hot the pump can't build injection pressure. Additives I use regularly are cetane booster and outboard motor oil (to compensate for the lubricity we refine out of it) and that tactic isn't working. Does anyone know of a more effective approach? Again, I apologize if I've offended anyone but I'm getting pretty frustrated with this problem.

aczlan · Jul 5, 2011

Mike in La. said:
The fuel gets hot enough to actually burn your hand if you pull the filter drain plug.

Can you measure the temp of the fuel coming out of the line from the tank and/or the temp of the fuel in the tank to quantify "hot"?
I would think that if the fuel was hot enough to burn you (140+ F) that the plastic fuel tank would be getting soft.

Aaron Z

LAWALLSTRACTOR · Jul 5, 2011

It is a metal tank on that model.

bindian · Jul 8, 2011

Mike in La. said:
This is gonna be long but please hear me out.....I have a 2006 6500FWD and when I need it to make a 10 hour day in 104 degree Texas heat, it won't and here's why: I work in a refinery and make diesel fuel. With the advent of our government mandating that we only make "ultra low sulphur diesel" (15 ppm sulfur max) the density and viscosity of the fuel is closer to that of naptha or gasoline.....not at all what we're used to running in our tractors. As the machine heats up with the fuel tank located where it is, the fuel gets too hot and thins (more heat = less viscosity) to the point that the injector pump will not put up the pressure to accomplish injection. The machine misses, loses power, and we all know what it's doing to the pump. I discovered this by checking for water at the filter drains the first time it happened and actually burned my hand with the hot fuel. Kubota and others got smart and moved their tanks. What will Mahindra do? Especially for the machines already out there with this design shortfall? I'll bet you're gonna sell lots of injector pumps. How about an insulation kit we can retrofit to our fuel tanks? Anyone else experiencing this after 8 hours in the 104 degree heat? Anyone have any ideas on an easy fix? I Love this tractor but am not about to buy a pump due to an engineering boo-boo. How bout it Mahindra guys, put your heads together and solve this.

I'm not a Mahindra guy, but...................
I ran my 6520 two weeks ago for 7 hours on Friday and 6 hours on Saturday at full rpm doing backhoe work on a pond and lake. The temp guage under my insulated canopy was bouncing around at 100 degrees, so the temp out in the sun was more than that. No issues noted.

My backhoe cylinders get too hot to touch, but never had a problem with fuel getting too hot in over 600 hours on the meter. Sounds like a fuel temp guage and cooler would benefit you. When I notice my water temp gauge getting past the mid mark, it is usually time for me to take a break and let the engine idle and bring the temp down.

You didn't state what you are doing on that 10 hour day in 104 degree Texas heat? Are you running at full rpm or just loping around? Have you installed any hydraulic line mods that are too close to the fuel line and heating it up? What was your water temp guage reading during all of this? Is your hydraulic and transmission fluid topped off? Not enough fluid can cause a heating problem, along with low engine oil.

FYI, when Mahindra changed the 6520 into the 7060, they moved the fuel tank just forward of the left step. Not sure where yours is. My 6520's filler neck is aft and left of the seat and the tank is left of the transmission, where it could pick up heat off of the tranny and differential.
hugs, Brandi