John C

Long story short. I destroyed my several year old HOB Spacewalker at the field Friday am, flew out of range of the park fly Rx, tho I'd flown it for years. Everything checked OK on the ground, except for the aileron servo with stripped gears.

Anyway, my OS Max needs a P/N 21181019 Carb Complete to get back in the air. Does anyone have an idea as to a source for this? The body broke at the mounting screws, but otherwise looks OK. The body is not shown separately in the parts list I have that came with the engine.

Any help appreciated.

Thanks,

John C

AMB

John you may be able to use an OS10LA carb needle o nback, throttle body on front martin

ffkiwi

I think you'll find a Thunder Tiger 10 or Magnum 10 carb will be a 1:1 replacement. I found both listed on a casual ebay search yesterday.

ChrisM
'ffkiwi'

John C

Thanks for the responses. I'll check on e-bay for a TT ot Magnum carb. Thinking last night, I may be able to CA glue the bottom of the carb back on, and retap the mounting screws as a fallback position. This could be kinda weak tho...

John C

Max_Power

Can you show a picture of where you broke? You sure dont want to glue something back together with the potential to break again and let debris enter the engine. If its just the retaining bolts broken post a picture and someone likely can help you with a alternate carb retention method if you aren't wanting to buy the LA or TT carb. Don't step over a dollar to pick up a dime and end up with a destroyed engine. Todd

John C

The carb broke through the threaded mounting holes of the spigot (part that inserts into the open venturi to make an R/C engine). Here's a pic looking down at the failed surface:

Preview does not support attachments, hope this comes across OK.

John C

fritzke

My Feedback: (1)

http://www3.towerhobbies.com/cgi-bin...?&I=LXAPFK&P=7

John C

Any idea as to the spigot diameter? The OS Max is 8.5 mm as best I can measure.

Thanks,

John C

Toysareforkids

My Feedback: (4)

Is this the same carb?
I do have a couple of OS 10 FSR's NIB that I can pull out and check it with, but I'll have to wait till tomorrow to do so. I have this carb I got from someone else awhile back, and am not using, if it fit's. I the OD bore is .356 & the ID is .220. these are the base bores.

Pat

John C

Carb certainly looks similar. My measurements are a bit different from what you show. My spigot ID is .209 and OD is .334, which equals the 8.5 mm above. I'd appreciate your checking a carb from your FSR versus these numbers.

Thanks,

John C

Toysareforkids

My Feedback: (4)

Well, not good!
My OS .10 FSR is the same size as yous is. The one I have is the same as the one on my OS .20 . If I remember right I got it to fit a OS .15 I had, and sold this pastspring without a carb, because I couldn't find it.

Pat

John C

Thanks for checking! I've got a name of a hobby shop that may specialize in older OS Max engines. I'll give them a try. Carb is disassembled for cleaning and then I'll try the CA fix.

John C

mkoe

PM sent, Don't try the CA fix. It can be repaired if you can't find one, if you don't try and glue it.

I TIG weld parts like this and then remachine them. I repair crankcases and mufflers on a regular basis that have been crashed. I have also done carb throats, but it needs to be as clean as possible and the glue MUCKS up the alloy and more has to be removed to get a good weld.
Mike

John C

Just an update. I bought the Thunder Tiger carb suggested in post seven by fritzke. It slips right in the crankcase bore, but does not have the threaded mounting screw holes [:@]. The threads are an unusual metric size, very close to a US 6X32 (they will thread several turns before locking up).

As my son is a toolmaker, my plan now is to ship the carb off to him with some 6X32 screws and let him drill and tap the mounting holes (location is scribed on the carb). He can do it much more accurately than I can. This won't happen until after Thanksgiving tho as I won't be home until then.

If the engine runs well with the new carb, the ultimate plan is to build a BMJR 1/2 scale Taurus (36" span) for this engine. A full scale Taurus was my first R/C plane in 1969 (and lasted six flights with my personally built Heathkit GD-19 radio).

John C