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Old Jul 18, 2010, 01:23 PM
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John
Just look at those crankcase backplate threads on that Norvel! Beautiful! Then compare to the shaft housing on my Mills

I was only half joking about the glowplug. If people are bothering heating up engines before starting, why not use the full-size glowplug notion - it need only be cheap resistive wire, not platinum. Then run the warmed engine on kero and oil.

I guess the throttling would suffer, when the engine cooled after idling, and perhaps prove old "PGFC" Chinn right at last!

I always put 5% unleaded gas in my "straight" glow fuel, instead of nitro, and get beautiful idling and no excessive heat (not at 5%, anyway!).
Apparently Nitro is not made in North America any more.
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Old Jul 18, 2010, 02:48 PM
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The windy west coast of Sweden
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Originally Posted by Chas View Post
I always put 5% unleaded gas in my "straight" glow fuel, instead of nitro, and get beautiful idling and no excessive heat (not at 5%, anyway!).
The manual that came with my old Merco 35 recommends just that, as an ignition improver at cold weather....

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Old Jul 20, 2010, 06:55 PM
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Canada, ON, Hamilton
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Post #996 shows a DC 2.5 diesel with a blue anodized cylinder. It has arrived. The engine isn’t frozen, but this exhaust ring has got to go. The diesel doesn’t appear to have been mounted, but there are “tool marks” on the flat spots on top of the cylinder. Below the cylinder fins there is a “muffler ring” and below the muffler ring there is a knurled ring that pushes the muffler ring upwards against the lower cooling fin.

Does anyone know if this knurled ring has left (LH) or right hand (RH) threads?
The “instructions” that came from DC don’t address dis-assembly.
The cylinder cooling fins are threaded on. I’m guessing both have RH threads, but I don’t want to be wrong.
The Merco is still soaking.
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Old Jul 23, 2010, 06:31 AM
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Chas

Quote:
Originally Posted by Chas View Post
John
Just look at those crankcase backplate threads on that Norvel! Beautiful! Then compare to the shaft housing on my Mills

I was only half joking about the glowplug. If people are bothering heating up engines before starting, why not use the full-size glowplug notion - it need only be cheap resistive wire, not platinum. Then run the warmed engine on kero and oil.

I guess the throttling would suffer, when the engine cooled after idling, and perhaps prove old "PGFC" Chinn right at last!

I always put 5% unleaded gas in my "straight" glow fuel, instead of nitro, and get beautiful idling and no excessive heat (not at 5%, anyway!).
Apparently Nitro is not made in North America any more.
Can you use 5% acetone instead of petrol , I was wondering ?
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Old Jul 23, 2010, 02:24 PM
Voices through wires? Ha!
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I don't know... http://pesn.com/2005/03/17/6900069_Acetone/ ....
apparently it drops the octane rating a lot. The fullsize buffs are putting teaspoons in truck gas tanks so we might easily overdose on 10cc !

I hate to keep banging on about oil, but it all boils down (:-0 ) to this - can anyone answer please? - if castor is preferred for its greater protection at higher temperatures, what is the point of lubricating anything above TDC? It's called a combustion chamber, after all. I always boggle at people saying a black exhaust means your oil is burning - of course it is, it's just been ignited under pressure! The question should be what lubricant is suitable for slicking the shaft, big end, gear trains, bearings, etc - all of which should be operating at temperatures way below even cooking oil flashpoints. And for the length of time oil, even in our "special case" fourstrokes, is in the engine, do we really think it picks up enough HEAT (as opposed to temperature) to flash off? You have to be hammering the engine way too hard in any case for that to happen, methinks.

What effect would acetone have on bearing seals, pump mouldings - even plastic venturis or backplates? And think of your nails....
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Old Jul 23, 2010, 08:03 PM
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East Anglia, UK
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Thing is chas, its the piston/cylinder slide fit that is the bad point. That tends to seize first IIRC.

Personally I think castor oil is all fluff and bo***ocks. Its what you use when you are too lazy to find out what's better
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Old Jul 23, 2010, 11:20 PM
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Keremeos, BC Canada
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Fluff? Okay, but Castor is just plain better at extremely high pressures and temperatures. On a BB engine, that ain't near as important, but plain bearing motors are a different game IMHO.

I cheat. I use 30% oil, BUT I use 15% castor, and 15% mineral, covering all the bases. Everyone knows that the two don't mix, but when one pours them into kero/ether, the kero stabilises the mineral, and the ether does the castor, and everything is happy.

Out here in the sticks, options for lubrication is not that great; besides, most of my engines are old, borderline collectors, and I just hate taking chances with engines I can't replace...
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Old Jul 24, 2010, 01:28 AM
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OK, this is about the best"GUFF" writen on oils and castor with reference to our model engines, realy worth a read :- http://www.modelenginenews.org/faq/index.html#qa5 , as it explains why Castor is the best.
Stewart

Following are a few extracts from the text:-
" Nearly all of the common synthetics that we use burn in the combustion chamber if you get off too lean. Castor oil does not, because it is busily forming more and more complex polymers as the temperature goes up. Most synthetics boil on the cylinder walls at temperatures slightly above their flash point. The same activity can take place in the wrist pin area, depending on engine design. "
and
" Most glow engines can get by with only a little castor oil in the oil mix, but diesels, with their higher cooling loads and heavier wrist pin pressures, thrive on more castor oil in the mix. "
I feel these are the relevent points concerning our diesel engines, its also relevent to the ball sockets of the Cox engines, its well known Cox's live longer on castor based fuel.
Stewart
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Old Jul 24, 2010, 04:14 AM
Voices through wires? Ha!
Chas's Avatar
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Originally Posted by vintage1 View Post

Personally I think castor oil is all fluff and bo***ocks.
Not everything is in boocks, Vint.

I couldn't agree more.

Guys, I take your points, but what I was trying to say is that it doesn't matter that castor has better high-temperature protection. As Vint has mentioned elsewhere, by the time you get to "high temperature" (eg., past the transfers on a two-stroke), lubrication is a historical issue.

Take the "better piston seal" argument. On a fourstroke you would get no lubrication at all for your crank, cams, pushrods, rockers or main bearings if Castor sealed off the rings. These engines depend on piston blow-by for the essential lubrication of the engine. Running a conventional fourstroke on high Castor is equivalent to banging it with a sledgehammer (which you will need later anyway to chip off the caramel.).

Clip, certainly things burn in the combustion chamber. The cylinder walls, and the wristpin, and everything else in the engine, however, are lubricated from below...if you are over 440F in the crankcase you'd better start doing something differently!

People are paranoid about "lean runs". Certainly, this raises combustion chamber temperature, but really the reason you see horrific graphics of holed pistons, tortured rods and cindered rings is that leaning reduces oil content in our sumpless engines. It's easy to enter the Heat Spiral by tweaking that needle too far, but really the answer is not Castor, it's just enough of a decent oil.

Just look at the technology of today, where engines are required to run at jaw-slackening temperatures for interminable periods with unquestionable reliability. Do they use Castor? Do they have to strip down an F-17 or Abrams engine and sand-blast it as they did on the Somme? Although Brandon was a High Security Area in the 1780's because of its rich flint deposits, I don't see the US Administration demanding Regime Change to protect the rich Castor Bean fields of India as a Strategic imperative. Come on guys, just say No.
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Old Jul 24, 2010, 04:35 AM
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In a pinch

can I run some of my car sump oil in my Chinese motors, I did get car starter fluid to work in it , it was the 24 % ether stuff , It ran not bad just long enough for my son to total the model

Im thinking that a small bottle the LPG gas laying on the ground with a rough aluminium duct to transfer the hot air from the flame uup past the cyl thereby heating it for a fast start , Oh darn LPG cyls dont work lying down I just remembered
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Old Jul 24, 2010, 04:42 AM
Voices through wires? Ha!
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Originally Posted by NX-687 View Post
It ran not bad just long enough for my son to total the model
How do you know?

Chinese engines run very well on Car Sump Oil, Beeswax, Column 2, Soy.... but I get phenomenal performance in my Yin Yan Silver Happiness with this..
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Old Jul 24, 2010, 04:47 AM
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Ahhha

Thinking about it I could use on of those butane soldering irons with a small aluminium duct over the diesel cylinder while I was rolling out the lines , then the engine would be at full temp on starting and fuel would be non critical , this would have to work
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Old Jul 24, 2010, 04:49 AM
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Chas

Quote:
Originally Posted by Chas View Post
How do you know?

Chinese engines run very well on Car Sump Oil, Beeswax, Column 2, Soy.... but I get phenomenal performance in my Yin Yan Silver Happiness with this..
You dont say

What exactly is that stuff ?, the engine looks good
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Old Jul 24, 2010, 04:51 AM
Voices through wires? Ha!
Chas's Avatar
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Why not connect your lines, shorted across the Cylinder Head, to a 16 cell Nicad at the handle? 20V @ 50A = 1KW. That oughta do it!
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Old Jul 24, 2010, 04:51 AM
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Chas

that is amazing , it looks green
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