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-   -   OS .40 engine question (https://www.rcuniverse.com/forum/beginners-85/6560348-os-40-engine-question.html)

ouflyer 10-30-2007 07:20 PM

OS .40 engine question
 
Hi all,

I have a chance to buy an OS .40 engine, new in box for 40.00. It's an older engine that is in a red/white box, with a remote needle valve kit that comes with it. It's all sealed, never been used. On the box it states it comes with a remote needle valve kit worth 9.99 for free. I've heard alot of good remarks on OS engines, and since I'm very new to this hobby, I was wondering if I should purchase this engine. What are all of your thoughts on this?

Thanks
CC

Mr67Stang 10-30-2007 07:25 PM

RE: OS .40 engine question
 
Sometimes the difference between a good deal and another dust collector is... Have you thought it out and have a plan as to what you will put this engine in? $40 is not bad for any New in Box OS engine. But if you don't have a use for it then it is or will be a... collectors item???

ouflyer 10-30-2007 07:40 PM

RE: OS .40 engine question
 
I'm not interested in keeping it as a collectors item. I want to use it. I just don't want to buy this engine and find out it not a reliable engine that OS owners claim they are. It's an early model engine, but its new, and I just want to know if I can expect the reliability the newer OS engines are. So if anyone has bought one years ago, in this type of box, i would like to know if they had good results with this engine.

Thanks
CC

iluvflying 10-30-2007 07:44 PM

RE: OS .40 engine question
 
There are two basic types of .40 engines from OS. One is a bushing engine FP and the other is a ball bearing engineSF,. Both are worth $40 and can be used in a number of RC aircraft. Some examples would be:

PT-40, Ugly Stick 40, almost any lightly built .40 size kit can be flown with these engines and don't break the bank on fuel.

If you don't buy it send me the address off line please:D


Philip in Texas

iluvflying 10-30-2007 07:46 PM

RE: OS .40 engine question
 
Just a quick update, I have owned a .40 FP OS engine for 14 years and it starts and runs whenever I need it to do so.

Buy the engine and trust me you won't be sorry.

Philip in TEXAS

horace315 10-30-2007 10:15 PM

RE: OS .40 engine question
 
i am still running a os fp.40 i got 20 years ago or so, still runs very strong and no problems i had it on a avistar in 1988.

ouflyer 10-31-2007 07:35 AM

RE: OS .40 engine question
 
Look's like I'll be getting me an OS engine then. Thanks all for your input.

Thanks
CC

hitman45 10-31-2007 08:02 AM

RE: OS .40 engine question
 
Me three!

I've bought myself (few months ago now), was a brand new in box O.S. .40FSR off eBay. Paid $120 or so for it but I cant believe how WELL the older engines run. My engine was first built back in 1975. Start first go everytime and could run all day long without a hitch. One thing to bare in mind is that, your should always run abit of Castor oil in your fuel through them. As these old timers will love you for it.

$40- bux is a bargain and if i was you, I'd buy it. You have nothing to loose and chances are, the person selling it to you hasnt got a clue about value. Wont be dissapointed with O.S. like someone said earlier. All my engines have been O.S. and I wouldnt change for the world.

crashcrash 11-19-2007 10:33 PM

RE: OS .40 engine question
 
LOL...my FP40 has been sitting since 1996, I just pulled it out. She was very dirty (burned varnish from fuel etc), and froze solid, couldn't even operate the carb. Soaked it in gas/2cycle oil mix, cleaned it off and it was still froze. Put it in a pan of water and boiled it for 10 minuets, she's freed up. Now the big part....clean it all back up spotless and get a new glow plug for it. It's a winter project, so no rush here. I had a supratiger .40...what a pile. This OS FP-40 always started easily and never quit in flight (on take off or landings). Been sitting for 11years, I think it'll still be fine. Found out they're obsolete for crying out loud. A simple, reliable, and inexpensive motor (all around great little motor), and they don't make them any more.

noahdear 01-14-2008 05:11 AM

RE: OS .40 engine question
 
I bought a 2nd hand OS 40FP off ebay for $81 as parts for my 40FSR (some bits are interchangeable). Any ideas what's a good prop size for these engines?

cheers

crashcrash 01-14-2008 05:55 AM

RE: OS .40 engine question
 


ORIGINAL: noahdear

I bought a 2nd hand OS 40FP off ebay for $81 as parts for my 40FSR (some bits are interchangeable). Any ideas what's a good prop size for these engines?

cheers
About 10x6 or 10x7 as a start. Mine has the 10x6.

noahdear 01-14-2008 06:25 AM

RE: OS .40 engine question
 
Beauty !!! thanks. I have a 10x7 on a Tigershark .46 and it seems ok.

The OS.40 FSR has a marine head and flywheel on it. I bought the 40FP to cannibalize for the head but it looks like the better (newer) engine, so I thought I might use it instead of converting the 40FSR back to an air screw. But the 40FSR seems to have much better compression. Is one better than the other, generally speaking?

They are saying over [link=http://www.rcuniverse.com/forum/m_6659566/anchors_6659767/mpage_1/key_/anchor/tm.htm#6659767]here[/link] that an 11x5 is good too. That gives me somewhere to start.

cheers !

crashcrash 01-14-2008 07:31 AM

RE: OS .40 engine question
 


ORIGINAL: noahdear

Beauty !!! thanks. I have a 10x7 on a Tigershark .46 and it seems ok.

The OS.40 FSR has a marine head and flywheel on it. I bought the 40FP to cannibalize for the head but it looks like the better (newer) engine, so I thought I might use it instead of converting the 40FSR back to an air screw. But the 40FSR seems to have much better compression. Is one better than the other, generally speaking?

They are saying over [link=http://www.rcuniverse.com/forum/m_6659566/anchors_6659767/mpage_1/key_/anchor/tm.htm#6659767]here[/link] that an 11x5 is good too. That gives me somewhere to start.

cheers !
The OS .40FP was the bottom end engine and it does lack power compared to others (so I have read). I believe this to be true because I had a supertiger .40 that had way more power. I think 11x5 is OK if you have the ground clearence or your run way is paved. I'm still running my FP .40 on an AeroStar .40 by MidWest. It's not much, but it flies good.

downunder 01-14-2008 09:50 AM

RE: OS .40 engine question
 
The 40FSR (actually all the FSR range) are still considered to be the best engines that OS ever made. Early engines were ringed and went to ABC in 1981.

SGC 01-14-2008 06:16 PM

RE: OS .40 engine question
 
My Son still uses my OS40H , 1972? vintage, its dead reliable starts first flick and has never quit in the air whilst it had fuel, not as powerfull as some later motors but a great sport engine.
Stewart

crashcrash 01-14-2008 06:59 PM

RE: OS .40 engine question
 


ORIGINAL: SGC

My Son still uses my OS40H , 1972? vintage, its dead reliable starts first flick and has never quit in the air whilst it had fuel, not as powerfull as some later motors but a great sport engine.
Stewart

LOL....my OS .40FP is COLD BLOODED. It starts OK at 50degF....below that, need an electric start.

noahdear 01-15-2008 05:16 AM

RE: OS .40 engine question
 
Actually it's for an airboat

Red B. 01-15-2008 07:39 AM

RE: OS .40 engine question
 


ORIGINAL: downunder

The 40FSR (actually all the FSR range) are still considered to be the best engines that OS ever made. Early engines were ringed and went to ABC in 1981.
It's right up there with the OS 40/46 SF. The SF series are slightly more powerful, quieter and just as durable as the FSR series they replaced.

opjose 01-15-2008 11:38 AM

RE: OS .40 engine question
 
IMHO the only issue would be parts availability and price with an older engine.

Mighty Mouse-RCU 01-16-2008 02:43 PM

RE: OS .40 engine question
 
If it comes with a remote valve, it cant be too old. Best engine I have ever had was an older OS 46 SF.

Ryan I. 01-16-2008 03:35 PM

RE: OS .40 engine question
 
I've got an old, varnished up .40 FP as well. A little low on power but it makes up for that with reliability. It just runs, and runs, and runs. Good little engine.

crashcrash 01-16-2008 04:05 PM

RE: OS .40 engine question
 


ORIGINAL: ForktailedDevil38

I've got an old, varnished up .40 FP as well. A little low on power but it makes up for that with reliability. It just runs, and runs, and runs. Good little engine.
Yep....they do. Maybe I need hotter plug to rectify the cold blooded tendencies eh? In the summer...first flip and she's running. Winter...forget it. And it does run good for what it is.


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