Low Sulfur Diesel, lubrication issues

[RWEST]

Currently, we're running 500 PPM Off-Road diesel in our pre-'07 backhoe/CUT's/Gator, etc... Do I need one of those additives, or only if/when running ULSD.

How about in our pre-'07 on road trucks, which ARE using ULSD?

 

[6sunset6]

First of all...they are talking about older mechanical injection pumps (plunger and barrel or delivery valves) which does not apply to any of the newer diesels (common rail injection). The newer engines that use common rail injection systems have a high pressure fuel gear pump which pressurizes the fuel rail to about 20,000 to 30,000 psi. The injectors are then actuated via electronic solenoids via the computer. No plungers or barrels in these engines.

And, these systems are designed to work on the new, low sulfur diesels so you would be wasting your money on additives on a common rail engine.

And to be honest, most inline mechanical injection pumps don't need these additives either because they are lubricated with engine oil via their own oil sumps or they share oil from the engine itself (although it doesn't hurt to add lubricity). The only injection pumps that need a lubricity additive are rotary injection pumps such as some of the older Stanadyne or CAV or Lucas pumps. Those rotary pumps use fuel for all their lubrication and the reduction in lubricity of fuel will reduce the longevity of these pumps. Stanadyne makes an excellent additive which improves the lubricity of fuel and I believe they are the only fuel injection component manufacturer to also make and sell an additive for their pumps.

Talk to a fuel injection shop to get the real skinny. I work closely with a shop which rebuilds all our pumps for us and they are a wealth of knowledge from the "front lines", so to speak.

I have a Perkins A3.152 in a MF Industrial Tractor . Has the CAV rotary injection pump ref above. I am having a problem with low idle , won't.
I think it is the lift pump and am putting in a new one. Got a note on another forum from someone who said it was the check valve on the return line. I don't see one exactly, just an adapter in the injection pump body to the the tubing connector. Anyone know if that adapter is a checkvalve ?
Seems like the diaphram in the lift pump was really shot. I had to change the fittings and tubes to the new lift pump so another couple of days to check it out . I have been using Power Service as an aditive, IS that ok or should I look for somethng else?

 

[Shimon]

I have a Perkins A3.152 in a MF Industrial Tractor . Has the CAV rotary injection pump ref above. I am having a problem with low idle , won't.

It could be a bunch of things. I would start with a cylinder balance test to see if one of the injectors is sticking at idle. When was the fuel filter last changed? If the fuel pump diaphragm is bad that could be it too (make sure you aren't dumping fuel into your oil).

Will it not idle in gear or out of gear? Is the idle speed set correctly? What is it set at? Does it run properly at higher RPMs loaded/unloaded? Original injectors? How many hours? Air leak? Lots of questions.

There probably is a restrictor in the return line (not sure about that engine)...the way you can tell is to remove the fitting on the pump which feeds the return line...probably a banjo fitting with bolt? The bolt will be narrowed down and sometimes there is a little screen in there too with a check ball/spring...it will look different than a normal banjo bolt fitting. Try soaking it in kerosene or solvent.

Power Service isn't bad but for better lubricity try Stanadyne or run a 5% biodiesel mix.

 

[Butters]

I just remembered that someone did a study of diesel lubricity after adding various flavours of snake oil to the mix. You can find it here.

While this link does provide some food for thought, it is pretty invalid from a scientific standpoint. There was no continuity among the amounts used, nor the price per treated tank, thus both amount and treate price are confounded by the mixing ratios tested. I don't mean to rain on anyone's parade, but this test does not hold water.

 

[rustyanchor]

While this link does provide some food for thought, it is pretty invalid from a scientific standpoint. There was no continuity among the amounts used, nor the price per treated tank, thus both amount and treate price are confounded by the mixing ratios tested. I don't mean to rain on anyone's parade, but this test does not hold water.

As I read the testing method, the products were bought retail and mixed to manufactures specifications for a 26 gallon tank of fuel. Makes sense to me, unless I'm missing something?

Mark

 

[john_bud]

As I read the testing method, the products were bought retail and mixed to manufactures specifications for a 26 gallon tank of fuel. Makes sense to me, unless I'm missing something?

Mark

Only that "butters" is not correct. Price per tank is a result - not a variable. Duh.

 

[Butters]

A response variable is a "result" as you would call it. You measure variables to estimate parameters DUH,
There are no true recommendations on how much two-stroke, or used motor oil to add to diesel. It is specualtion. There woud need to be a dose response curve established.

Only that "butters" is not correct. Price per tank is a result - not a variable. Duh.

 

[john_bud]

If you feel the need to map the variable response space, sure. But if you just want compare resulting lubricity at recommended doses, why do that? The study was designed to compare lubricity chemicals.

Experiments cost money. The study was funded by individuals, not government, university or industry so only a comparison of the lubricity chemicals at label rates was conducted. If you would like to fund further investigations, you can contact the poster from the link and supply him with the funds. If memory serves, each test costs about $4-500 + the cost of the fuel, chemical and shipping.

enjoy
jb

 

[Butters]

If you feel the need to map the variable response space, sure. But if you just want compare resulting lubricity at recommended doses, why do that? The study was designed to compare lubricity chemicals.

Experiments cost money. The study was funded by individuals, not government, university or industry so only a comparison of the lubricity chemicals at label rates was conducted. If you would like to fund further investigations, you can contact the poster from the link and supply him with the funds. If memory serves, each test costs about $4-500 + the cost of the fuel, chemical and shipping.

enjoy
jb

I personally don't care, I just hate see people quote bad science as gospel. It was a good starting point, but it in no way provides definitive answers to the questions origionally asked. Also, there are no "label rates" for two stroke gasoline oil in diesel fuel. I have better things to do rather than give statistics lessons on a tractor forum. I am here to learn, but when I see something that I can contribute to, I will. The one ounce rule for two stoke oil etc is likely a wives tail, or whatever you want to call it. I am not saying it won't work, but why is one ounce the best?
Far better science is discounted by the general publlic, but publish something like this on a non-peer reviewed web page and people think it is the holy grail. I give up.

 

[Technoid]

I own a Dodge truck with the Cummins 12 valve mechanical injection pump. The only additive that Cummins recomends is Stanodyne. I use it in all my old diesel engines. I buy it by the 5 gallon can. About $125 online order. Had no problems at all with injection pumps. I have been using it for years.