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Engine basics => Engine set up tips => Topic started by: Don Curry AMA 267060 on March 09, 2010, 08:43:03 PM
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In a box of engine parts that I received from a Friend I put together part of an OS 32F. It is missing the piston rod and liner. Tower no longer lists parts for this engine and I would like to put it back into service. Does anyone have any parts?
To the best of my memory they had 2 models of this series, one was ringed for helicopter use and the other was abc for aircraft use. I am not sure if the porting is different for the two versions.
Don
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Hmm there must be 3 versions, I have one that is not ringed but has a steel P/L I bought it years ago when Bob Hunt was using one on his RD 1 project, they are not good stunt motors and require reworking to keep them from running away, I cut two shims from a coke can to go between the Liner and case this seems to have changed the porting and lowered the compresion enough to tame it, I'm going to try it one more time and if it still runs away on me you are wellcome to have it.
Dwayne
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Thanks for th offer Dwayne. I remember useing these engines and also the ASAP 32's in r/c and they were about the size of a 25 but had as much or more power than most 40's. I also have a Mac,s header and tuned pipe for this engine but I don,t know if it could be made to work for c/l.
Don
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#^ Mornin guy's, I have been runnin' OS 32 SX engines for several years now, and the changes that we have made are these; reduce the "squish band" to about half, and block the boost port off completely, then run a mixture of castor/ synthetic fuel using a Thunderbolt w/ idlebar and prop's 10x4 & 10x5 APC at about 10,200-10,500.
Fluin in models weighing about 45-48 oz on 62' lines from eye to eye.
On the mixed fuel I have been using Powermaster 5-10% nitro and 22%oil half/half however the castor can bee reduced to about 5% and syn upped to 17%.
The little motor are STRONG !!!
Of course your milage may vary...
And this in NO WAY is to discredit anyone...Also we are usin ST needle assy's with about a .272 venturi at sea level mostly...
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I run the OS-32F On my RD-1. Lots o power. I'll look to see if I have any extra parts as I do have a couple of them.
Scott (close by) Riese
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I run the OS-32F On my RD-1. Lots o power. I'll look to see if I have any extra parts as I do have a couple of them.
Scott (close by) Riese
Hi Scott what mods did make to it?
Thanks
Dwayne
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I don't want to hijack the thread but if anyone has a spare head i could use it. I have a heli version with the conversions done to it but i need to replace the heat sink head, No lathe to turn down the head.
Dennis
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I don't have a lathe either but I have redone a heli head by scribing the outline, using a band saw to cut close to the line and finishing up with my bench mounted belt sander. It looked very professional when it was done.
Don
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Thanks Scott. I am not in a big hurry, just another project.
Don
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Dennis.......I have the lathe.
My OS 32F's Were reworked by Tom Lay. HOWEVER, if you have one Here's what you can do so as too get rid of the runaway. One extra head shim. Props.. 10.2x3.8 or 10.5x 4 two blades...I run a three blade GATOR 10x4 at 10,500 on 62 foot lines.
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When Billy Werwage was running the OS 32F, he told us to use a tongue muffler and keep blocking the holes until the right run was achieved. it needs a good bit of back pressure to run correctly. We did it and Aaron's Ares flew several years with the set up, no problems. We used BY&O 10-5 props which came out to 4 - 4 1/2 pitch on the Prather gauge.
Ward had used the engine on a pipe in one of his Force models for a while before Aaron bought it from him.
And as an aside, I have the original Webra 28 that Bob Hunt used in the Tucker Special he published. It had the opposite of the Fox burp. It would always burp with it mounted inverted. Bob shaved the fins off the head, made a tin collar for the engine case to hold in heat, etc., but he finally put a Webra 32 in the Tucker. Robby used the Webra 28 on his RD-1 when he built his and so did we. No problems with it side mounted. We used true 4 pitch props (and sometimes a touch less pitch) on all the Webras.
Mongo