Notices
Everything Diesel Discuss R/C Diesel engines here.

OS 1.60FX Diesel

Old 03-02-2014, 10:26 AM
  #1  
N99JH
Thread Starter
My Feedback: (66)
 
Join Date: Jun 2002
Location: Hartsville, SC
Posts: 382
Likes: 0
Received 2 Likes on 2 Posts
Default OS 1.60FX Diesel


I bought a brand new OS 1.60FX and broke it in with a Zinger 20X6-10 propeller for about 90 minutes total run time. Very, very sweet and powerful engine, but - of course that is precisely what I have come to expect from OS after 47 years in the hobby.
Just to establish a reference point, I mounted a 22-10 Zinger and ran it at full power - 5,000 RPM but of course quite high fuel consumption.
I than switched to the Davis Diesel head and ran it with my Xoar 24-6 cut down to 23-1/4: 5,000 rpm slightly rich, 6 minutes @ 4500 rpm on a 6 Oz. tank. Compares very well to what I got on the ST 3000.
I ordered a Zinger 24-8 and 24-10 and will test them next on exactly the same setting.
My goal is still to fly a Hostetler's Fairchild 24 (27% scale) at SCALE SPEED with a SCALE PROP. Hopefully it will fly in a scale manner at 3500 - 4000 rpm which is a very sweet spot in terms of noise (almost scale) and engine longevity.
Here are the first ever pictures of a 1.60FX Diesel that I am aware of. All my attempts to find anyone who ever operated this engine as a diesel on the Internet have come empty handed.
Attached Thumbnails Click image for larger version

Name:	100_5790.JPG
Views:	158
Size:	496.8 KB
ID:	1974079   Click image for larger version

Name:	100_5791.JPG
Views:	160
Size:	510.3 KB
ID:	1974080   Click image for larger version

Name:	100_5792.JPG
Views:	165
Size:	462.6 KB
ID:	1974081  
Old 03-08-2014, 07:58 AM
  #2  
N99JH
Thread Starter
My Feedback: (66)
 
Join Date: Jun 2002
Location: Hartsville, SC
Posts: 382
Likes: 0
Received 2 Likes on 2 Posts
Default

Update:
I bought a O.S. 40B carburetor as used on the 40 & 46 FX. The throat is 13.5 mm while the hole in the crankcase is 15 mm so I used thin aluminum shim stock wrapped around the throat to bring it as close as possible to 15 mm outside diameter. It fitted pretty well in the crankcase and produced the same 5000 rpm as with the Xoar 24-6 (cut down to 23-1/4). This time though I can open the throttle to wide open without having the engine bogged down.
I swapped a Zinger 24-10 and the engine runs great at up to 4400 rpm without over heating - ever so slightly rich with a hint of bluish smoke. Reliable idle is down to about 1200 rpm and cold starts almost instantaneous, typically 2 to 3 flicks get the engine running
I am very happy with the performance so far.
Old 03-15-2014, 06:43 AM
  #3  
N99JH
Thread Starter
My Feedback: (66)
 
Join Date: Jun 2002
Location: Hartsville, SC
Posts: 382
Likes: 0
Received 2 Likes on 2 Posts
Default

Final Update
I bought a brass sleeve that OS makes for the 40B carb to fit into the 50SX. The sleeve fits nicely and I drilled two holes for the retention screws. The assembly fit snugly into the crankcase and all air leaks were eliminated. The best starting procedure is to open the throttle to 40-50%, choke and flip the props 2-3 times. Usually after the 3rd flip the engine pops and ready to run. Flipping the prop another 2 times without choke gets it running every time. Allowing about 20 seconds for warm up, the rpm stabilizes and runs steady at about 3000 rpm. Transition is instantaneous and I tried both a Zinger 24-8 and 24-10. Max rpm was 4600 for the 24-8 and 4400 for the 24-10. Idle was very reliable at 900 rpm. for both.
Incidentally, the 40B carburetor (from a 40/46FX) works great at 65% throttle area as compared to the original 160FX carburetor.
Old 03-15-2014, 07:20 AM
  #4  
earlwb
 
earlwb's Avatar
 
Join Date: Aug 2009
Location: Grapevine, TX
Posts: 5,993
Likes: 0
Received 3 Likes on 3 Posts
Default

That has to be quite impressive and I bet it sounds nice too. That big single would tend to sound quite realistic at the low RPMs like that.
The diesel converison is sort of icing on the cake, so to speak.
Nice.
Old 03-15-2014, 07:52 AM
  #5  
N99JH
Thread Starter
My Feedback: (66)
 
Join Date: Jun 2002
Location: Hartsville, SC
Posts: 382
Likes: 0
Received 2 Likes on 2 Posts
Default

You are absolutely right Earl.
Being somewhat eccentric and interested in out of the well proven concepts, I was somewhat hesitant loading a 24 in. prop on 1.6 Cu.In. engine but the only way to find out was by doing. I knew all the nay sayers would recommend against it. I am glad I did because it taught me how to properly set up a Diesel once and for all and confirmed what I knew for a long time - Torque is what spins your prop, not HP. The Diesel may not produce more power than a glow perhaps but it sure produces WAY MORE torque at lower rpm. The thrust produced at 3500- 4500 rpm is considerable and 900 rpm idle would be impossible to beat unless one fly's electrics.
Old 05-21-2014, 02:52 AM
  #6  
capin
Member
My Feedback: (11)
 
Join Date: Jan 2002
Location: ellicott city, MD
Posts: 82
Likes: 0
Received 2 Likes on 1 Post
Default

Great, I am glad someone else is doing the bigger diesels now. I did the 160 around 7 years ago and was running the st 2500s 3250s and a 4500 having a blast! If you search way back you should find some info, I remember running a 26-8 off my 3W 85cc twin.it was way more then it could take but if I remember i think around 4000 rpm. A 24 would be her max even a 23", but still you cannot beat the torque. Brian ps I also did a asp 80 4 stroke and flew the plane for a couple of years on the same diesel fuel as the rest. Testing is most rewarding- sometimes-

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.