ST51 Overcooling

Stuka Stunt Main Forum · 6 of 6 known posts recovered

paul allen · May 20, 2004 09:12 AM

Here in OZ we are coming into winter,my Aldrich ST51
is overcooling any suggestions on setup to cure this
and still keep that 2/4 run,ie larger dia prop,drop oil
content a little,more back pressure from muffler,at present
using a 4C plug, 23 percent oil, 1/2 Klotz,1/2 Castor,5 percent
Nitro,wood 2 blade,12x5.25,hauling a 62oz SV11,any idea's appreciated.

Paul Allen

Bill Little · May 20, 2004 09:17 AM

#1 source

Maybe a little "racer's tape" over part of the air intake, or outlet openings? Might allow you to run your present set up.
I ran almost the identical set up for several years. My SV-11 was 64 oz. Sweet combination.
Bill <><

When the character of a man is not clear to you, look at his friends.
Japanese Proverb

SRiese5283 · May 20, 2004 02:37 PM

#2 source

OR....I do this with COX engines. take a piece of tin foil about 1/2" wide and rap it around the fins of the cylinder and wire the foil to it. WORKS.

Scott(just glad to be here)Riese

Scott Riese

downunder · May 21, 2004 04:22 AM

#3 source

Well I have to say that here in Adelaide I've never had to worry about overcooling

but my G51 gave all the symptoms of overheating on 20% all castor (compounded I think because it's incredibly economical) and a switch to 25% all castor transformed it. Seeing you're using 23% oil I'd first try cutting it back a little.

pmflyer · May 24, 2004 08:05 PM

#4 source

Paul,

How do you know that the motor is over cooling? Please decribe in detail what symptoms the motor is exibiting.

Mikwe

paul allen · May 25, 2004 04:08 AM

#5 source

Mike,
When the glow starter is removed it drops engine rev,s
by a fair margin,level flight it sounds like its missing in
4 cycle and at the end of the flight the cylinder head is cold
enough to leave your hand on it,when the nose is pulled up it
try's to enter 2 cycle but its a late switch.Tried a Thunderbolt
4 cycle plug,22% oil 1/2 &1/2,klotz & castor,5% nitro,12x5.25 wood
2 blade,blocked 2 hole's of in T/muffler,had 6 flights last weekend
air temp was 10 degree's C in the morning rising to 22 degree's at
1.00pm.The last flight at 1.00pm was spot on no drop off when glow
driver removed.Strong 4 cycle run through all the flight.
Based on the other reply's I made a sheet brass band about 10mm wide to slip on the head to cut down on air flow through the fins for
early morning flights have not tried this yet.
Paul Allen

Paul Allen