Adding old oil to fuel?

[tigertank]

My dad used to add used oil to his old diesels like the 6.2 in old gm trucks and the old fors 7.3 non turbo he never had any issues with them and got 500,000 out of all his trucks? Can we do this to the 6.2in the humvee???

 

[Dock Rocker]

I use 2 stroke oil. It really helps lube the injector pump. The new low sulfer stuff doesn't lubricate well.

 

[Suprman]

I have heard of guys adding atf, which is basically oil with additives, as extra lubricant in the diesel. I don't see any reason you shouldn't be able to add a quart to a tankful of fuel.

 

[Dock Rocker]

You will be shocked at how much quieter your engine runs. It really surprised me.

 

[tigertank]

COPY THAT will let evone know how it runs lol

 

[DatGuyC]

You will be shocked at how much quieter your engine runs. It really surprised me.

It made my 6.2 knock a bit, I thought a rod bearing was going bad or something. Stopped adding the 2 cycle and the knock went away.

 

[camoyj7]

I have a 6.2 diesel in my 91 Chevy k2500 and I use to run 25% filtered waste motor oil all year long. It ran great but didn't like the smell of the exhaust.

 

[Dock Rocker]

It made my 6.2 knock a bit, I thought a rod bearing was going bad or something. Stopped adding the 2 cycle and the knock went away.

I am not doubting your experience but I wonder how adding lubrication caused a knock? How much did you use? I am adding 16 oz per tank.

 

[DatGuyC]

I was adding the same, about half a quart when I filed it up. It started when I started adding it and stopped when I didn't, so it's the only thing I changed. I'm thinking that the different combustion properties of the oil changed either the start or duration of the combustion and that caused the knock. It wasn't super loud but I'm a little ocd about the sounds the engine makes, it's usually pretty quiet for what it is minus those noisy v belts.

 

[tonkasal]

You can do it, the only caveat is if you are running a spin on high micron fuel filter, it's going to get gunked up and possibly cause air lock.

 

[Shark Bait]

2-stroke oil has no ash content when combustion is done if I remember correctly. We use it in all our diesels without the newer emissions.

Dave

 

[eaw46]

Be careful about adding ATF as the red dye is the same as that used for no tax off road fuel. If you get your tank dipped by DOT you can end up in a lot of trouble. Eddy

 

[tennmogger]

Tigertank did say 'used' oil. There's a huge difference between adding 'aged' motor oil or adding 'used' motor oil. The first would have no impurities and latter does, in abundance.

An engine might run great with used oil added. But why add oil that was taken out of an engine with 10 thousandths clearances (to avoid further engine wear), and running it through an injector pump with an order of magnitude tighter clearances.

There are huge threads on here about how to process 'used' motor oil before running it through an IP. Search on WMO. At least those processes reduce the size of the abrasives!

Tigertank, please be sure you understand the implications of some of the advice you have been given. Diesel is not that expensive right now. My 2c.

 

[Scar59]

Tigertank did say 'used' oil. There's a huge difference between adding 'aged' motor oil or adding 'used' motor oil. The first would have no impurities and latter does, in abundance.

An engine might run great with used oil added. But why add oil that was taken out of an engine with 10 thousandths clearances (to avoid further engine wear), and running it through an injector pump with an order of magnitude tighter clearances.

There are huge threads on here about how to process 'used' motor oil before running it through an IP. Search on WMO. At least those processes reduce the size of the abrasives!

Tigertank, please be sure you understand the implications of some of the advice you have been given. Diesel is not that expensive right now. My 2c.

Spot on, unless WMO is pre-filtered before introducing into the fuel supply, stay away from it. Long term effects will cost you. Better to use a proven diesel additive. Power Service Diesel Kleen or fresh 2 stroke oil.

 

[73m819]

Use 2 stroke, not used motor oil, the ip will not like the acids and over time you will have a cokeing issue unless you run for long periods of time, running around town will not keep the engine hot enough over a extended time frame. If you are going to run used motor oil, filter it down till ALL the soot, bits of metal, and trash is gone and not ware the ip., there is the acid issue. The Gimp is the only person that I know that has his waste motor filtered CLEANER then pump diesel.

 

[DainGerous]

Pulled this off the net (Discuss amongst yourselves.). Looks like a 1:200 2 cycle oil mix seems common. 25Gal = 3200 oz/ 200 =16oz 2 cycle oil to the full tank.:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=279116

Don't mean to be critical here, but need to raise the yellow flag. Before and during the first Gulf war, the real test of the single fuel policy (i.e., using JP-8 in both ground and aircraft) occurred. That surfaced the lubricity problems when using a kerosene fuel (such as JP- in the lighter duty diesel engines (e.g., GM 6.2L/6.5L)that were fitted with fuel lubricated rotary distributor fuel injection pumps. However, the fuel that was used was not JP8 but the commercial industry standard Jet A-1 which has no requirement for any additives that would give any measure of lubricity improvement. Well, when pump wear and hot starting problems began to surface, the soldiers in the field starting using a variety of "band aid" fixed such as engine oil, ATF, brake fluid, etc. The Army did some laboratory testing using the Stanadyne DB Fuel Pump and found that of all the add-ons, the only one that seemed in reduce the wear problems in any way was the ester based aircraft turbine engine oil (MIL-PRF-23699). ATF and the other products did not show any positive results. So if anyone hears that ATF is good to solve these "low lubricity problems," they are not giving the facts correctly. Even the pump manufacturer (Stanadyne) came on record and said the same. There are several additives available in industry that help to improve the low lubricity of kerosene fuels and these are the way to go instead of the ATF supposed fix.

A more serious problem in using kerosene type fuels in diesel engines occurs when the engine is operated in real hot weather such as exists in Irag. With the type of fuel pump as is found in HMMWVs, the fuel's viscosity become so low that insuffient amounts are pumped into the cylinders causing a hot engine restart problem and power loss. Unfortunately, there is no easy way to increase a fuel's viscosity. Additives simmply cannot correct this problem.

**
When I had it available I did use 10-10 turbine oil. But I have found the 2-cycle oil to be the best, first of all because it is ashless and the injector 2-cycle does contain up to 18% Stoddard Solvent for cleaning. Second it is always available through supply channels. JMO
**

 

[tigertank]

good advice!! Ive been using a elcheapo ATF and its sure seems to run quitter and better

 

[Mike82ndABN]

I alternate between stanadyne performance (same manufacturer as the injector pump), and diesel kleen

 

[99nouns]

I am not doubting your experience but I wonder how adding lubrication caused a knock? How much did you use? I am adding 16 oz per tank.

Is that the off the record recommendation adding 16oz 2cycle oil per (what) 75gal tank for A2 truck?

 

[Trailboss]

I have a couple of drums of unused but probably 15 years old rotella-type motor oil that I don't want to use as lube oil in my engines due to the age. I've been adding 1 gallon of that clean unused oil plus 1/2 gallon of new Quicksilver 2-cycle oil per 55 gallon drum of diesel when I fill it up at the store. That comes to about 2% clean lube oil and 1% 2-cycle oil. I use this fuel mix for the NHC250, 8.3, 6.2, 6.5, 7.3-turbo engines, and the 60hp Perkins in my Massey Fergusson farm tractor. Could easily double those percentages with no issue except cost.

When I pick up a new truck, I also add a quart of Diesel Kleen to the first tank fill-up. I don't have to worry about fuel gelling here.

Haven't really noticed any improvement or degradation in any of the engines (they might run slightly quieter), but none are high mileage engines except the '96 7.3 Powerstroke. The 7.3 F250 has just under 400K miles with the original injectors and glow plugs but has been using the mix for only about the last 50K miles. The M931A2 and M925 trucks do get heavy use hauling hay and flat-towing other trucks, but they already run very well so I don't know if the fuel mix helps or not.