OS 40LA or 32F

[smark]

I am rebuilding a trainer, sort of bashing an old GP PT40.
I have an OS 40LA and a 32F. Are these engines for the most part interchangeable? That is, aside from the dimensions, can the 32F be expected to perform better than the LA? The weight is approximately the same, and the published HP of the 32F is a little higher than the 40. Recommended prop sizes overlap.
Am I missing something?

[Kevin McGrath]

I have run many OS engines over the years,and still own half a dozen including a 40LA.This is a reliable,relativley cheap,easy starting unit,but its tuned very mildly,doesnt use ball bearings and is no powerhouse.If your other engine is a ball bearing unit it probably does develop as much thrust as the .40 with less displacement.
Dont pay too much attention to manufacturers horsepower claims......these are often exagerated or represent a peak reached with high RPM and a small prop,which has little bearing in the real world,especially with begginer type engines and planes........IMO.
Maybe another reader knows more about your .32 unit and will chip in......

Kevin

[rcpilotsteve]

I have an OS40LA on my sons trainer. Good running engine. I run mostly Heli's myself! I have a few 32F-H engines. Probably the same as your 32F with a Heli head etc etc...... so a comparison between yours and mine would be fair. I break the ringed engines in on the bench with a prop. (Yes, Andrew even the new .32SXH ringed :) ) I can tell you the 32 swings a 10x6 prop a lot easier than the 40 does. I switched to a 12x6 on the 32 and I still have to watch the RPM. I would say the .32 has at least 30% more power over the 40LA. My sons 40 is a great runner, it does everything we need it to do. It is a bit sluggish down the grass runway though.
Hope this comparison helps......

[AJCoholic]

I have also run the 40 fp and la engines, and also the older OS 32 and newer 32 sx engines (and the 34 super tigre which is close to the os 32 in output) and I have to say the little 32 heli engine is a brute! It will easily fly a 40 size trainer with authourity allthough my prop of choice is a 10-5 APC on the 32 engines, while I like the 10-6 or 11-5 on the 40's.

Either will do the trick, I'd use the LA 40 and save the 32 for something like a profile fun fly that will benifit from the lightweight power plant.

Also, the 32's runs AWESOME on a mousse can muffler if you havent tried one you should. More power (1000 to 1500 rpm increase) and they are also a very effective muffler.

Andrew Coholic

[smark]

Thanks for all the comments guys.
What is the difference between an airplane engine and the heli version, besides the head cooling fins? The 32F came in both versions, mine being the airplane version, but are they essentially the same?
Thanks!

[JimMcIntyre]

I'm not overly familiar with these particular engines (I sold the 32 with my Nexus heli and I traded my LA after 2 flights) but, generally the increased cooling fins and a different carb (more linear throttle response) are the two main differences. Plus mufflers are not generally included with most heli engines.

HTH!

Jim.

[Hughes500E]

They are essentially the same. Same crankcase , same Carb etc etc. However the internals are slightly different !!!! Heli engines have to put up with a lot more abuse....... :lol:

[kersplat]

Alos on this topic, the .40 LA has two transfer ports in the sleeve which open later. The .32 has three larger transfer ports which open sooner, thus more BHP.

[Fastsky]

If you are referring to the 32SX then I would say go for it! It will turn a 10-6 prop over at the same speed as my 40FX, is lighter, quieter, and uses less fuel. It is very easy to adjust and puts out tremendous power for such a small quiet engine! OF course you do pay mucho extra for it! 8)