RunRyder RC
WATCH
 1 page 121 views POST REPLY
HomeRC & Power✈️Aircraft🚁HelicopterEngines Plugs Mufflers Fuel › will an OS 91 backplate fit the OS 70SZ
04-01-2020 05:06 AM  59 days ago
Topic Vote0Post 1
Gearhead

rrMaster

Vt

MyPosts All Forum Topic
will an OS 91 backplate fit the OS 70SZ
Guys, I have a NIB OS 70sz, I want to put a 91 Regulator on it, will the Pumped 91SX or Hz back plate fit the 70sz ?

I think they will fit, but I got to be sure.

thanks !
Jim
Buzz Buzz Buzz
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
04-01-2020 07:34 AM  59 days ago
ticedoff8

rrKey Veteran

Morgan Hill, CA. USA

MyPosts All Forum Topic
I don't know.
But, I bet not.
The .61 to 1.05 use the same mounting lugs (big block), but not the same crankshaft.
Buy the backplate for the .91 1st and try it before you buy the carb.
Or, drill and tap a nipple to the .70's backplate.
+ > ÷
Believe 1/2 of what you see and none of what you hear.
Fake News will be the downfall of our Republic!
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
04-01-2020 01:17 PM  59 days ago
wjvail

rrElite Veteran

Meridian, Mississippi

MyPosts All Forum Topic
💎Sustaining Member
Like Ticed said, I don't think they will interchange. I don't know what is different but they are different part numbers.

Again, as Ticed suggested, I wouldn't hesitate to drill and tap your .70 backplate. If you do choose to tap your backplate, make sure the pressure nipple doesn't extend into the case too far and touch the rod. You may have to shorten the threaded portion of the nipple.

https://www.towerhobbies.com/cgi-bi...p?I=LXCM34&P=ML

https://www.manualslib.com/manual/6...?page=15#manual
"Well, nothing bad can happen now."
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
04-01-2020 07:32 PM  59 days ago
Rojoalfa

rrKey Veteran

Punta de Mata, Monagas-Venezuela

MyPosts All Forum Topic
/
/

Both rear bearing are the same for os91hz and os70sz.

https://www.amainhobbies.com/o.s.-e...7930000/p141309

Base on that dimensions, probably both backplate works without problem.

/
Saludos cordiales,
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
04-01-2020 07:32 PM  59 days ago
JLF92677

rrApprentice

Southern California

MyPosts All Forum Topic
Gearhead will an OS 91 backplate fit the OS 70SZ
Guys, I have a NIB OS 70sz, I want to put a 91 Regulator on it, will the Pumped 91SX or Hz back plate fit the 70sz ?

I think they will fit, but I got to be sure.

thanks !
No, it will not fit. Dimensions are different. Bolt center hole to center hole dimension is smaller on the 70 than 91.
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
04-02-2020 06:59 AM  58 days ago
Gearhead

rrMaster

Vt

MyPosts All Forum Topic
OK, thanks ! I don't have a problem drilling and taping but I don't know how thick the back plate is, I will have to take it off and measure it, if it's too thin I will only get 1 or 2 threads in it. I have a friend that has been welding for some 55 years. I can have him put a drop of aluminum on it, them mill it flat and drill and tap it

thanks guys !
Jim
Buzz Buzz Buzz
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
04-02-2020 07:35 AM  58 days ago
JLF92677

rrApprentice

Southern California

MyPosts All Forum Topic
Deleted.

Jim, after reading your last post again this morning I realized that I misunderstood your post, as your response was to post #2
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
04-02-2020 08:29 PM  57 days ago
Gearhead

rrMaster

Vt

MyPosts All Forum Topic
it was for all my RR friends for trying to helpJim
Buzz Buzz Buzz
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 1 page 121 views POST REPLY
HomeRC & Power✈️Aircraft🚁HelicopterEngines Plugs Mufflers Fuel › will an OS 91 backplate fit the OS 70SZ
 Print TOPIC  Make Suggestion 

 4  Topic Subscribe

Saturday, May 30 - 7:54 pm - Copyright © 2000-2020 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online