Walter Pollux vs. Walter Super Castor

[AMCKen]

Yes, another query.

Are these the same engine? Same size and time frame. 135mm x 170mm 9 cylinders c.1930 onwards.

thanks again

 

[Shortround6]

Yes, another query.

Are these the same engine? Same size and time frame. 135mm x 170mm 9 cylinders c.1930 onwards.

thanks again

Perhaps not. 1938 "Janes" says the Super Castor used a 146mm stroke for a displacement of 18.8 liters while the Pollux used the longer stroke for a displacement of 21.9 liters.
Other differences seem to be the Super Castor used a reduction gear while the Pollux was direct drive, Super Castor turning a max of 2400rpm to the Pollux's 2000rpm. Super Castor was also supercharged, mildly. Pollux did use a centrifugal 'blower' turning at crankshaft speed, probably for mixture distribution as much as anything else. Super Castor had a FTH or Critical altitude of 2000 meters?

Perhaps earlier engines were different?
Castor II was a seven cylinder Pollux with the 170mm stroke.

 

[AMCKen]

Perhaps not. 1938 "Janes" says the Super Castor used a 146mm stroke for a displacement of 18.8 liters while the Pollux used the longer stroke for a displacement of 21.9 liters.
Other differences seem to be the Super Castor used a reduction gear while the Pollux was direct drive, Super Castor turning a max of 2400rpm to the Pollux's 2000rpm. Super Castor was also supercharged, mildly. Pollux did use a centrifugal 'blower' turning at crankshaft speed, probably for mixture distribution as much as anything else. Super Castor had a FTH or Critical altitude of 2000 meters?

Perhaps earlier engines were different?
Castor II was a seven cylinder Pollux with the 170mm stroke.

My sources showed all 3 and the Venus and Vega as 135x170.
That would make the Venus as just 110hp from 17 litres and that doesn't seem right.

Any info on the Regulus and Mars also? Just your basic bore/stroke hp.

TIA

 

[Shortround6]

Sorry, they are not listed in this edition of 'Janes'. There are a Gemma I, Scholar I, Bora II and a Bora II-R (reduction gear) from 7.8 to 9.35 liters and 150hp to 230 hp. (international). all nine cylinder radials with small cylinders.
Are these engines from the early Thirtys?

 

[AMCKen]

I have the Scolar (?) at 105x100x9 for 7.79L.
No info on the Gemma or Bora.

Yes, around 1930-36. The Regulus and Vega as 5 cylinder, Castor and Venus as 7 cylinder, Mars as 14 cylinder, and the others as 9 cylinder.

 

[Shortround6]

Here is a bit more on the Walter engines.

Gemma I--105mm bore x 120mm stroke-9 cylinders-9.35 liters normal HP 150 at 1785rpm. compression ratio 5.3/1 68 octane. Pushrod tubes are wider apart at crankcase than at cylinder head.

Scolar I has cylinders as you describe. normal HP 160 at 2200rpm, compression ratio 5.4/1 octane 73.
Push rod tubes start out one behind the other and get wider going up to cylinder head.

Bora II is back to the 105mm X 120mm cylinders but with the staggered push rod tubes like the Scolar. 210hp at 2200rpm normal compression ratio 6.3/1 octane 75.

Bora II-R adds a 2:3 reduction gear for 230 hp at 2400rpm octane 80.

It is noted that Walter was building or had built the Bristol "Mercury" and "Pegasus" as well as the Gnome-Rhone 14K.

another source says that Walter built 17 different radials from the 20s onward, including 2<edit 3 > , 5, 7, and 9 cylinder models.

 

[AMCKen]

Would the 14 Cylinder Mars be the 14K copy?
And what about the Venus? Apparently a large engine but with little HP.

thanks for your help.

 

[Shortround6]

It could be. I tried looking on Wikipedia but their listing of Walther engines is a mess. There is no way that a 14 cylinder radial ( which they picture) produced under 200hp like they list in the planes that used the engine sections.
the listing of different Walter models is impressive even if details are lacking or confused.

 

[AMCKen]

Wiki is where I started looking, and where I got the bad info. I've got another reference here now and will see what other stuff I can figure out. I'll get back to you on what else I need and post a 'revised' result for you. Perhaps I'll fix up wiki too. : )

 

[nosorozec]

Sorry for my very bad English.

Walter and Walter Pollux Super Castrol were the same engines. Basic information:

Walter Pollux II

a) Rotating Propeller: right-handed
b) reduction ratio:
on the propeler: without reducer
on the the compressor: without compressor
c) Number of cylinders: 9
d) Radial engine
e) Bore: 135 mm
f) Stroke: 170 mm
g) engine capacity: 21,9 l
h) Compression ratio: 6,0
i) engine power:
1) normal: 340 ks at 1800 rpm
2) maximum: 450 ks at 2000 rpm
j) weight: 325 kg
k) fuel: Aviation gasoline with minimum octane number 75
l) consumption in kilograms per hour: 83
m) oil type: mineral
n) Normal oil pressure in kilograms per square centimeter: 4,0
o) oil consumption in kilograms per hour: 5,8
p) Normal oil temperature: 75 degrees Celsius
q) Maximum oil temperature: 90 degrees Celsius
r) Carburetors:
1) Number: 1
2) Type: Stromberg NAR 80
s) Magnets: Scintilla GN 9-DSCN
t) Fuel Pump:
1) Number: 1
2) Type: Jumo
u) Starter: pneumatic or mechanical
v) Dynamo: power 400 Watts
w) Dimensions:
1) Diameter 1262 millimeters
2) Length 1110 millimeters
x) firing order: 1-3-5-7-9-2-4-6-8

Propeller shaft was solved according to the Czechoslovak standards (ČSN).

Walter Super Castrol I MR

a) Rotating Propeller: right-handed
b) reduction ratio:
on the propeler: 0,666
on the the compressor: 7,6
c) Number of cylinders: 9
d) Radial engine
e) Bore: 135 mm
f) Stroke: 146 mm
g) engine capacity: 18,8 l
h) Compression ratio: 5,8
i) engine power:
1) ground level:
a) normal: 400 ks at 2200 rpm
b) maximum: 480 ks at 2200 rpm
2) at an altitude of 1750 meter:
430 ks at 2200 rpm
j) weight: 355 kg
k) fuel: 50-20-30 with minimum octane number 85
l) consumption in kilograms per hour: 111
m) oil type: mineral
n) Normal oil pressure in kilograms per square centimeter: 4,0
o) oil consumption in kilograms per hour: 7,7
p) Normal oil temperature: 40 degrees Celsius
q) Maximum oil temperature: 75 degrees Celsius
r) Carburetors:
1) Number: 1
2) Type: Zenith 100 I A 160
s) Magnets: Scintilla LV 9-D
t) Fuel Pump:
1) Number: 1 or 2
2) Type: Walter Jumo
u) Starter: pneumatic
v) Dynamo: power 400 Watts
w) Dimensions:
1) Diameter 1188 millimeters
2) Length 1411 millimeters
x) firing order: 1-3-5-7-9-2-4-6-8

Propeller shaft was solved according to the Czechoslovak standards (ČSN).

Czechoslovak Air Force before World War II used to power aircraft, aviation fuel, which was a mixture of gasoline, benzene and alcohol. This mixture is called Bi-Bo Li, and also dynacol (it was a brand name). Individual motors used different ratios of the components and required some clean gasoline (without benzene and alcohol). Standard conditions were 50% gasoline, 20% benzene and 30% ethanol. The basic raw material was gasoline octane number of 65, which was imported from Romania (from oil fields in Ploiesti, which were later bombed by U.S. aircraft). Czechoslovakia and Romania prior to World War II Allies. The fuel is mixed in Czechoslovakia under these conditions and the resulting fuel octane numbers were around the 85. Other ingredients (such as tetraethyl lead or iron pentacarbonyl - German "Motyl") is not enjoying as in the case of mixtures of alcohol failed to increase the octane number of the resulting mixture. Walter Pollux Engine II require clean gasoline with minimum octane number 75, Walter Super Castrol I MR used a combination of 50% gasoline, 20% benzene and 30% ethanol, minimum octane 85.

Octane number should match C.F.R. method to be used (if you know) and the USA. Maybe not exactly agree with you used C.F.R method, some European countries before World War II used a modified method with different input temperature of the mixture. Czechoslovakia used unmodified C.F.R method. Consideration, however, the transition to the method of measurement used in France, where lower initial temperature of the mixture in the experimental engine. This transition is already before the war, but probably not.

Overall, the pre-war Czechoslovakia, a total of 6 companies that manufactured piston aircraft engines. I know a total of 65 different types of engines. The largest producer, Walter and Avia, smaller producers were ČKD, Tatra, Orion and arms factory in Brno, Czechoslovakia. They made all sorts of engines from a liquid-cooled V-12 cylinder, radial engines over to diesel radial aircraft engines.

In terms of materials used in the Walter engine piston aluminum alloy Hiduminium RR 59. For this you will probably alloy known as Rolls-Royce RR 59 (High Duty Alloys Ltd.). Small engines have a Walter engine blocks of magnesium alloy. Heads of engines manufactured from aluminum alloy Y. It will also definitely known you over the ocean, was developed around 1921 at the National Physical Laboratory in Teddington. Before the war was also used in Czechoslovakia. Engine crankshaft Walter Pollux II was forged from steel, called Poldi L Victrix Specials. It was a product of Poldi Kladno, and it was steel with additives of chromium, nickel and molybdenum. The second engine I do not know.

Again, sorry for my English, I write it through Google Translator.

 

[AMCKen]

Thanks for this information. It helps a lot. : )