Page 1 of 1

Model Engine Oil (lubrication)

PostPosted: Tue Sep 07, 2010 1:16 pm
by raptor22
I have read through your article on oil and am overjoyed to find that someone in the RC industry Gets It!!

Oil content in the fuel should be determined by oil quality rather than a blanket percentage.

Like you allude to in your artcile, the european fuel companies use esterified oils in their fuels. These oils provide tremendous film strenght when compared to PAG oils which are mostly used in synthetic gearbox or circulating oils where high speed moving parts are less likely.
A fact that many miss, is that in a model engine the lubrication is mostly hydrodynamic in nature and therefore low viscoisty oils are preferable (Especially in ringed engines) but with a high retention of viscosity across temperature change (called Viscosity Index to us folk in the Lubricant industry)

I know of at least one Euro Methanol fuel company that produces a 10% fuel with high quality esterified lube in it but few are willing to buy it out of fear of engine failure because it has been drummed into them that more oil is better.

Thanks for fighting the good fight on this one. Look forward to your reviews of model engine fuels and I hope you are able to pick the molecules apart to establish whats in there.

Re: Model Engine Oil (lubrication)

PostPosted: Wed Sep 22, 2010 6:20 am
by jeffie8696
Too bad we in America can not get the "good oil". :(
So we putter along with large amounts of "bad oil'.
Thats OK, I have plenty of paper towels to wipe my plane off with, I shall survive until it changes.

Re: Model Engine Oil (lubrication)

PostPosted: Wed Sep 22, 2010 7:48 am
by RCModelReviews
Yes, I find it interesting that, unlike most of the rest of the world (where you *can* get good oil), Americans end up running higher nitro levels to compensate for the extra viscous drag their higher oil contents create.

What you gain with one hand you lose with the other ;-)

Re: Model Engine Oil (lubrication)

PostPosted: Thu Sep 23, 2010 2:04 am
by jeffie8696
Yup, we dont make no sense sometimes. :lol:

Re: Model Engine Oil (lubrication)

PostPosted: Sat Nov 13, 2010 5:50 am
Regarding 'good oil' and 'bad oil'. I have had excellent lubrication results blending glow fuel with jet turbine oil (Polyol ester). I mixed the turbine oil 50-50 with Polyalkylene glycol (which used to be available from Union Carbide, now defunct). Fuel mixture was 10% total oil (50-50 blend). This worked great in high performance "piped" racing engines. For sport flying, I blended 5% turbine oil with 10% glycol for a total oil content of 15%. The higher oil percentage was not necessary for lubrication, but was for increasing the viscosity of the fuel. The throttles (especially the needle valves) of most glow engines are not designed for low-viscosity fuels. The 15% total oil content fuel gave significantly more power and RPM than typical commercial fuels. This fuel blend worked very well in 'piped' engines.

Re: Model Engine Oil (lubrication)

PostPosted: Sat Nov 13, 2010 10:37 am
by RCModelReviews
FASSTFLIER wrote:Regarding 'good oil' and 'bad oil'. I have had excellent lubrication results blending glow fuel with jet turbine oil (Polyol ester).

The only problem with some turbine oils is that they're not designed for a total-loss lubrication system and can produce very toxic combustion by-products when burnt due to organophosphate additives. Reference (PDF)

Fortunately, many of the newer turbine oils claim to have very low levels of neurotoxicity -- however, that's generally as measured by way of skin-contact, not vapor inhalation as would be the case when using large percentages (5%+) as premix in the fuel of a 2-stroke engine.

Turbine oil is also often quite expensive and can also stain the finish of your lovely model, especially because most types tend to go a dark color over time when mixed with methanol :-(

Re: Model Engine Oil (lubrication)

PostPosted: Thu Feb 17, 2011 7:57 am
by human213
Objective testing and procuring higher quality oils...

yes, I will be waiting for those reviews with heli four stroke needs much better...


Re: Model Engine Oil (lubrication)

PostPosted: Sun Nov 27, 2011 1:04 am
by rinkhals01
Hi there chaps.
I heard xjet talk about the virtues of Cooper oil and as I now live in western Australia and I cannot find any info re the Cooper oil ( let alone where to buy it). What grade and type of oil are you using in your 2 stroke motors, and can it be used in 4 strokes as well?

I also would like to take a second to sing the praises of Xjet who is so sharing with his rc experience with the wider world, that I find it a breath of fresh air that a man can be so generous with his time time and experience with out any avaricious intentions.....thanks very much pal and I hope that we do send him a small donation as a token of appreciation for all his hard work and passion to the RC fraternity.

Cheers Rinkhals01