Fuel viscosity change with increased oil ratio

[Master Oil Racing Team]

What he told you about thinning vs lubrication is correct Sam, and here is just one example of why that might be necessary.

Before the advent of modern oils, sperm oil was the preferred cutting oil for the tough jobs. After it was banned, Omark Industries found that they could reduce their scrap pile significantly with the use of Master Oil due to properties coming closer to sperm oil than anything else on the market at that time. They could further reduce their losses by cutting it in half with Shell Sol 70. Why would diluting help keep their machine work within tolerance? It was because they were boring a small hole in extremely hard metal 28 to 30 inches. The deeper they got, the more circulating restrictions they had, and by thinning the oil, it was able to stay up with the bit. They were boring out rifle barrels, and that meant exacting tolerances. They had a big loss ratio until they did that.

Very interesting stuff.

[Powerabout]

M75
can you ask your guys if the oil forms part of combustion?
Does it burn once ignited?
or
Does it only support combustion
or
Does it not burn

Cheers

[Mark75H]

I asked. I was told although it is difficult to ignite, it burns as part of the main combustion.

[zul8tr]

Your testing procedure is very similiar to that used in the industry to measure viscosity but the equipment is somewhat different than what you are using. None the less the device you are using will do a good job for relative measurements but here are suggestions for use:

1. Do not drain the burette empty for each test run only measure the time for a volume to release say 30cc that keeps the fluid released in the graduated constant cross section region of the burette. There are dynamic flow regime reasons for this control. In doing the test start the flow at the full mark of the burette and start the timing when a selected top mark is reached and stop the timing at the lower mark. Repeat to get average time per each fluid test. This will eliminate the transient starting flow conditions and eliminate the dynamic flow conditions at the nozzle outlet and confine the flow release to the constant area section of the burette and hopefully laminar flow conditions. If flow times are to quick reduce the size of the exit orifice to assure laminar flow in the burette measuring region.

2. To maintain a nearly constant temperature of the tested fluid place the burette in a surrounding container of water of large enough volume to maintain the temperature of the fluid you are testing. Devise a sealed means to have the burette discharge out the bottom of this container. This is the temperature control procedure used by ASTM for the Saybolt device described below.

The most popular measuring device for low viscosity fluids is the Saybolt Universal Tester Viscometer. With it a 60 cc of fluid is drained thru the graduated portion and the time recorded. The device is calibrated with a known viscosity fluid but equations are available if calibration is not done. The calibration or equations will provide the kinematic viscosity in units of Centistokes (cSt) which if needed can be converted to Centipoise (Cp) knowing the specific gravity of the fluid. Both units are used in the industry.

Details are provided in Section 1.11 and Section 14.21, "HandBook of Fluid Dynamics" by Victor Streeter Ed. In Chief, 1st Ed 1961 McGraw-Hill Book Co, .

[7500Blizzard]

While the results of this test will be interesting i just don't see how it will help you decide on any tuning as it in no way replicates what your motor will be or is doing. To say that it takes point .001 seconds longer to flow 60cc's means nothing. There are 100+ different things that'll effect your fuel system. 1st your system is pump fed not gravity, than anything from how many hard bends in fuel lines, condition of inside of line, strength of pump/s condition of carb and so on. As stated above the biggest concern of extra or over oiling would be the leaning condition.

[Mark75H]

While the results of this test will be interesting i just don't see how it will help you decide on any tuning as it in no way replicates what your motor will be or is doing. To say that it takes point .001 seconds longer to flow 60cc's means nothing. There are 100+ different things that'll effect your fuel system. 1st your system is pump fed not gravity, than anything from how many hard bends in fuel lines, condition of inside of line, strength of pump/s condition of carb and so on. As stated above the biggest concern of extra or over oiling would be the leaning condition.

It looks like you are saying extra oil slows down flow thru your entire fuel system including the fuel pump. If that was the case not even increasing jet size would help.

I'm not clear on why you say viscosity only applies to gravity induced flow

[Mark75H]

only measure the time for a volume to release say 30cc that keeps the fluid released in the graduated constant cross section region of the burette.

That's the way I've been doing it and plan on doing it for the better video

2. To maintain a nearly constant temperature of the tested fluid place the burette in a surrounding container of water of large enough volume to maintain the temperature of the fluid you are testing. Devise a sealed means to have the burette discharge out the bottom of this container. This is the temperature control procedure used by ASTM for the Saybolt device described below.

Rather elaborate and necessary for assessing to a standard ... but I am not assessing to a standard, I only want to know how the particular mixes flow relative to each other, so I will only take it as far as monitoring and recording the temperature room temperature and the mixes to assure there is no change more than 2° at most. Since room temperature puts us squarely on the flattest part of the temperature/viscosity curve of the stuff being tested, that should be pretty good.

Is there any barometric pressure concern in the standard? I would think there is not.

[7500Blizzard]

No i'm not saying oil slows it down throughout your system although it most likely does atleast minutely in a gravity fed system. What i'm saying as it will prove nothing to help in tuning as it will not replicate anything your motor does. In order to prove anything you would have to replicate a typical fuel system to get any real usable data, and even then it would still vary from motor to motor.
I am also not saying viscosity only effects gravity fed systems although it will more than a pressurized system again all i'm saying is this test will give you nothing to use in the aid of tuning your motor.

[Mark75H]

I agree with that.

It will only show one particular aspect and how much that aspect can affect tuning.

[zul8tr]

That's the way I've been doing it and plan on doing it for the better video



Rather elaborate and necessary for assessing to a standard ... but I am not assessing to a standard, I only want to know how the particular mixes flow relative to each other, so I will only take it as far as monitoring and recording the temperature room temperature and the mixes to assure there is no change more than 2° at most. Since room temperature puts us squarely on the flattest part of the temperature/viscosity curve of the stuff being tested, that should be pretty good.

Is there any barometric pressure concern in the standard? I would think there is not.

ASTM has no barametric standard for the viscosity test that I am aware of.

Along with room temp also measure the gas oil mix temp but if gas and oil containers are stored in the same room that not be needed.

What will you be using to measure the temps: simple small mercury thermometer, infra red gun or other?