HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old May 10, 2012, 04:26 AM
Registered User
Australia, QLD, Booyal
Joined Aug 2011
985 Posts
Discussion
Mongrel engine

Alright. I recently bought a second hand plane and the engine which was installed i quite literally a mongrel. It has an os 60 fsr h (helicopter apparently) an os 72 replaced with a 7b carby but yet to bet a screw for it and the gold aircraft head. Will these things affect it much? Also if it would not work how much would all the parts be individually?
scrubmonkey is offline Find More Posts by scrubmonkey
Reply With Quote
Sign up now
to remove ads between posts
Old May 10, 2012, 07:56 AM
Registered User
earlwb's Avatar
USA, TX, Grapevine
Joined Dec 2008
13,593 Posts
If the engine runs OK, then go for it. The head won't affect it all that much. Worst case is the engine might tend to run too cool which could affect its performance on colder days, but in the summer when it is hot and humid, it won't have as much power loss from heat sag. But folks have run the heli engines on model airplanes already many times. The heli-carbs tend to be wrong for airplanes, which is why they swap out the carb for a airplane carb.

If the engine doesn't work, your best bet would be to get another engine instead of trying to fix it.
earlwb is offline Find More Posts by earlwb
RCG Plus Member
Latest blog entry: My new Gaui X5 Rc Helicopter
Reply With Quote
Old May 10, 2012, 06:18 PM
Registered User
Australia, QLD, Booyal
Joined Aug 2011
985 Posts
Is the 7b carb an airplane one? I seem to remember seeing them on an ad for an airplane engine at some point. The problem i think it was the 72 carb had now low end needle valve instead it had different pins that you put in and i didnt have any of the others and the low end was too rich
scrubmonkey is offline Find More Posts by scrubmonkey
Reply With Quote
Old May 10, 2012, 06:48 PM
Who Dat!
GeetarJoe's Avatar
United States, LA, New Orleans
Joined Sep 2011
650 Posts
if the barrel slides in and out laterally then it would probably be unsuitable for airplane use. if its the regular rotating barrel type it should be okay depending on whether it rotates in the correct direction.
GeetarJoe is offline Find More Posts by GeetarJoe
Reply With Quote
Old May 10, 2012, 06:58 PM
Registered User
Australia, QLD, Booyal
Joined Aug 2011
985 Posts
The 7b carby twists and moves in and out at the same time (e.g. The more i rotate the barrel the more it moves out, if i close the throttle the barrel rotates back in a bit)
scrubmonkey is offline Find More Posts by scrubmonkey
Reply With Quote
Old May 10, 2012, 07:49 PM
Registered User
N99JH's Avatar
Hartsville, SC
Joined Apr 2006
902 Posts
Quote:
Originally Posted by scrubmonkey View Post
The 7b carby twists and moves in and out at the same time (e.g. The more i rotate the barrel the more it moves out, if i close the throttle the barrel rotates back in a bit)
That should not present any problem. Many airplane carbs move sidways as they rotate. Just fire the engine and see how it runs - like Earl suggested.
N99JH is online now Find More Posts by N99JH
Reply With Quote
Old May 10, 2012, 07:54 PM
Registered User
Australia, QLD, Booyal
Joined Aug 2011
985 Posts
I need to get an idle stop screw for it as it was missing it when i got the carby. Next time im at the lhs ill check out the spares for one
scrubmonkey is offline Find More Posts by scrubmonkey
Reply With Quote
Old May 12, 2012, 05:19 PM
Registered User
earlwb's Avatar
USA, TX, Grapevine
Joined Dec 2008
13,593 Posts
Unless the idle stop screw affects the carb such as it lets the barrel come out, then you do not really need it. The idle speed can be controlled from the servo and end stop adjustment via the TX. So you may be able to run the engine without the little screw. The screw is a small metric screw and you might have one in your parts bin too. Some screws have a smaller tip filed into them too. But it is hard to say which one your carb has until you try one to see how it fits and works.
earlwb is offline Find More Posts by earlwb
RCG Plus Member
Last edited by earlwb; May 13, 2012 at 12:07 AM.
Reply With Quote
Old May 13, 2012, 03:45 AM
Registered User
Australia, QLD, Booyal
Joined Aug 2011
985 Posts
Yes the 7b carby the barrel rolls out and in with the rotation so it really needs it. Am going down to the lhs soon to pick up a new needle for an os 46 max fx as it keeps sucking air in from around it and none of the shops ive looked in have a small enough o-ring
scrubmonkey is offline Find More Posts by scrubmonkey
Reply With Quote
Old May 13, 2012, 08:42 AM
Registered User
earlwb's Avatar
USA, TX, Grapevine
Joined Dec 2008
13,593 Posts
Try a watch repair shop. They usually have a assortment of small O-rings for repairing wrist watches, etc.
earlwb is offline Find More Posts by earlwb
RCG Plus Member
Latest blog entry: My new Gaui X5 Rc Helicopter
Reply With Quote
Old May 13, 2012, 08:12 PM
Registered User
Joined Jun 2011
1,547 Posts
The 7B carb came on the old OS60FSR. It needs the idle stop or the barrel will fall out.
datsunguy is offline Find More Posts by datsunguy
Reply With Quote
Old May 13, 2012, 09:09 PM
Registered User
Australia, QLD, Booyal
Joined Aug 2011
985 Posts
Ive noticed that. Im waiting till my parents can get me down to the lhs to get a spare
scrubmonkey is offline Find More Posts by scrubmonkey
Reply With Quote
Old May 15, 2012, 06:48 AM
Registered User
epoxyearl's Avatar
United States, MD, Elkton
Joined Oct 2011
9,170 Posts
You probably know,but the barrel moves away from the needle valve as it rotates,automatically adjusting the mixture,as it does that.
epoxyearl is offline Find More Posts by epoxyearl
RCG Plus Member
Latest blog entry: Wheeling and dealing..
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Alert Thieving Mongrels grumpy1942 Australia 3 Mar 27, 2012 12:47 AM
Sold TRex mongrel. $150 RTF with your RX jim breese Aircraft - Electric - Helis (FS/W) 1 Jan 10, 2012 05:52 PM
Sold new lower price on Mongrel motowncali Aircraft - Sailplanes (FS/W) 1 Oct 13, 2011 03:15 PM
Sold new lower price on mongrel motowncali Aircraft - Electric - Airplanes (FS/W) 0 Oct 13, 2011 01:13 PM
Sold Mongrel 39" pylon racer motowncali Aircraft - Sailplanes (FS/W) 5 Oct 13, 2011 01:11 PM