I’ve made the decision to put an O-320 in my airplane. It’s a few years from being completed, but I wanted to ask the group where they look when it’s time to find a good deal on a used engine, a core for rebuilding, used factory parts, etc. Basically if a good deal comes up, I want to snag it and put it on ice until it’s time to hang it on the fuselage. 

Since we’re on the topic, any pointers on what to look out for, good and bad? I have the Lycoming manual and the lists of all the different variants of this engine (man there are a lot), and I know that the crank and case halves will need to be tested for cracks. The famous “yellow tag”, has anyone been burned in buying something that looked ok but wasn’t? Or is the presence of the tag a near guarantee of useable parts?

Going for the purple Venn diagram of cost, reliability, and lightweight. 150hp vs 160hp is not as important to me as 150 is plenty, I think certain variants of the 160 hp variants are lighter weight, though. I assume it will come down to what is available at the time of purchase.  I plan on doing all the engine work myself, and as long as it doesn’t start burning piles of cash or make me less confident in reliability, I will consider lightweight sump, EI, flywheel, starter as a method of keeping the weight down. Any other suggestions would also be appreciated. 


Views: 515

Reply to This

Replies to This Discussion

I am doing a similar build with my O-235 C2C. I was foolish and jumped on the first 235 I found. Certain parts for the C variant are universal among most all 235's out there. Others are not. The piston rings alone were almost $1,500 compared to $600 or so for the L2C. New pistons are hard to find. Some machine shops will not touch my older cylinders. If I could do it over, I would have sought out the more abundant L2C. I am also adding an electronic ignition. I don't know much about the 320's, but I am sure there are similar issues like I am having with my C2C. I believe you will need a case splitter to separate the case halves. Regardless, I have committed myself to this path and I will see it through. 

I found mine locally through eBay. Make sure you get the log book. If the engine is dismantled, it was done so for a reason. Be careful when buying an engine that is mostly in buckets. Many bolts, primer lines, etc. are time consuming and expensive to source out. Try to fond a complete assembled engine with most if not all the accessories. You can disassemble it yourself, replace the worn parts, and send the cam, case, cylinders,  and crank out for service. Get a copy of a parts manual for your engine, and an overhaul guide. Read, Read, and Read it some more. Educate yourself, and get a good set of micrometers that read out to ten thousandths of an inch. Check 8130 tags for the date of service. I've seen some yellow tags dated thirty years ago. That's a long time to sit in a shelf. 

Anyway, good luck and trust your gut. 



Thank you for the detailed response from your experience. I took careful notes. 

I hadn’t thought to watch eBay. I’ll include it in my sweep, with caution, of course, as always. 


Look at Wentworth, Texas air salvage, Barnstormers....

From the Type Certificate data sheets

O-320- Weight (dry) and ignition, dual. By Models
Weight Lb.

-A1A, -A1B, -A2A-A2B, -A3A, -A3B ---- 244lbs
-A2D ---- 249lbs
-A2C, -A3C ---- 243lbs
-B1A, -B1B, -B2A ---- 250lbs
-B2B, -B3A, -B3B ---- 250lbs
-B2C, -B3C ---- 249lbs
-B2D ---- 283lbs
-B2E ---- 250lbs
-C1A, -C1B, -C2A ---- 250lbs
-C2B, -C3A, -C3B ---- 250lbs
-C2C, -C3C ---- 249lbs
-D1A, -D2A ---- 255lbs
-D1B, -D2B ---- 254lbs
-D1C, -D2C ---- 256lbs
-D1D ---- 253lbs
-D1F, -D2F ---- 255lbs
-D2G ---- 251lbs
-E1A, -E2A ---- 244lbs
-E1B, -E2B ---- 243lbs
-E1C, -E2C ---- 245lbs
-E1F, -E2F ---- 248lbs
-E2D ---- 249 lbs
-E2G ---- 249lbs
-E2H ---- 252lbs
-E3D ---- 249lbs
-E3H ---- 252lbs
-E1J ---- 245lbs
-D2H ---- 251lbs
-D2J ---- 255lbs
-D3G ---- 251lbs
-H1AD ---- 253lbs
-H2AD ---- 253lbs
-H3AD ---- 253lbs
-H1BD ---- 253lbs
-H2BD ---- 253lbs
-H3BD ---- 253lbs

150 hp   (low compression pistons) will do well on car premium gas  

0-320 s   are one of the most abundant engines out there.

FYI, I just finished a Cruzer with a 0-320 E2D, wood prop, STOL gear, all primed and insulated, many extras....

Weighed 975 lbs and I set the gross at 1500 lbs.  5.7 G ultimate load (down from 6 G's)

I just posted an O-320 in the classified section. It has zero time and is still banded to the pallet in its original crate from Lycoming. 


I imagine your engine will be worth more than our budget, but what are you asking for it?



Z801 - Richmond VA

It sold shortly after I posted it. I was asking $22.5k. I sold it for $20k. I had purchased an uncompleted RV-6 kit from an estate. Then I decided that I didn't wat to build the RV. I sold the engine and airframe kit separately. 


New from Zenith:

Zenith Planes For Sale 

Classified listing for buying or selling your Zenith building or flying related stuff...

Custom Instrument Panels
for your Zenith

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, Dynon and Garmin avionics, and more.

Zenith Homecoming Tee:

Zenair Floats

Flying On Your Own Wings:
A Complete Guide to Understanding Light Airplane Design, by Chris Heintz

Builder & Pilot Supplies:

Aircraft Insurance:


West Coast USA:

Pro Builder Assistance:


Transition training:

Lavion Aero

K&S Aviation Services

Aircraft Spruce & Specialty for all your building and pilot supplies!

How to videos from HomebuiltHELP.com

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit HomebuiltHelp.com for the latest DVD titles.

© 2024   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service