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aznitronut 09-03-2010 09:26 PM


Originally Posted by hambone (Post 7896241)
Mine sizzles inside with .3 shims. Just tried that today. I must have an airleak.

Do you know what the shim sizes are? You can spray nitro cleaner or motor spray around the carb, or back plate, pinch bolt, if the engines dies, thats where the air leak is. check back plate seal also.

hambone 09-03-2010 10:21 PM


Originally Posted by aznitronut (Post 7896286)
Do you know what the shim sizes are? You can spray nitro cleaner or motor spray around the carb, or back plate, pinch bolt, if the engines dies, thats where the air leak is. check back plate seal also.

I had .3mm shim in it, or .012" USA language, lol. I guess i should call Uriah about this one. I'm about ready to slap a standard C6 head button on it if i can't get it straightened out soon. When i broke it in it had .020" shims in it and didn't get any hotter than 235 deg and come to think of it the thing was sizzling inside that day when i cut it off.

cdc 09-03-2010 10:29 PM


Originally Posted by hambone (Post 7896448)
I had .3mm shim in it, or .012" USA language, lol. I guess i should call Uriah about this one. I'm about ready to slap a standard C6 head button on it if i can't get it straightened out soon. When i broke it in it had .020" shims in it and didn't get any hotter than 235 deg and come to think of it the thing was sizzling inside that day when i cut it off.

What %fuel are you using.

hambone 09-03-2010 10:31 PM


Originally Posted by cdc (Post 7896474)
What %fuel are you using.

30%

cdc 09-03-2010 10:49 PM

The engine or the fuel tank might have an air leak.

hambone 09-03-2010 11:05 PM


Originally Posted by cdc (Post 7896524)
The engine or the fuel tank might have an air leak.

This is the only engine i have with problems. I'm gonna add shims tomorrow and seal the backplate. Never had to seal an engine before. All the o rings look great. This engine has a break-in and 1 day of racing in my friends buggy and hasn't functioned properly since. And come to think abt it that's when i went from .020" shims to .012" shims because somebody else that raced one told me the RB manual said .012"(.3mm) was the proper shimming. OS is so much easier, lol.

TIX 09-03-2010 11:11 PM

It sounds like have an air leak

if you dont want it ill be glad to purchase it off you

tc5 man 09-03-2010 11:12 PM


Originally Posted by hambone (Post 7896557)
This is the only engine i have with problems. I'm gonna add shims tomorrow and seal the backplate. Never had to seal an engine before. All the o rings look great. This engine has a break-in and 1 day of racing in my friends buggy and hasn't functioned properly since. And come to think abt it that's when i went from .020" shims to .012" shims because somebody else that raced one told me the RB manual said .012"(.3mm) was the proper shimming. OS is so much easier, lol.




dont , give up on it i have a rb s5 and im on my second gallon and somehow got it to run and start and run about 235 @.

i run the stock shims because i run 20% ebmods race blead.

its pretty fast.

runs good !

cdc 09-03-2010 11:17 PM


Originally Posted by hambone (Post 7896557)
This is the only engine i have with problems. I'm gonna add shims tomorrow and seal the backplate. Never had to seal an engine before. All the o rings look great. This engine has a break-in and 1 day of racing in my friends buggy and hasn't functioned properly since. And come to think abt it that's when i went from .020" shims to .012" shims because somebody else that raced one told me the RB manual said .012"(.3mm) was the proper shimming. OS is so much easier, lol.

0.20 shimming is proper shimming for 30% fuel.

aznitronut 09-04-2010 05:49 AM

Does the engine still have good pinch on the piston and sleeve? If you only have a break in and one day on track, it's not totally broken in yet, get your shims straightened out, and be patient, engines will tend to run hotter till fully broken in.

hambone 09-04-2010 09:26 AM


Originally Posted by aznitronut (Post 7897145)
Does the engine still have good pinch on the piston and sleeve? If you only have a break in and one day on track, it's not totally broken in yet, get your shims straightened out, and be patient, engines will tend to run hotter till fully broken in.

It's broken in. I took it to the track at least 10 times only to put one my other engines on for racing since the RB wouldn't function properly. I'll get some lucky 7 tomorrow and put shims back in. I keep hearing a OS .25 calling my name! Pain in the ass Italian engines, lol.

cdc 09-04-2010 09:35 AM


Originally Posted by hambone (Post 7897772)
It's broken in. I took it to the track at least 10 times only to put one my other engines on for racing since the RB wouldn't function properly. I'll get some lucky 7 tomorrow and put shims back in. I keep hearing a OS .25 calling my name! Pain in the ass Italian engines, lol.

It should run better with 0.20 shimming.

hambone 09-04-2010 11:22 AM

Took shimmimg to .020" and ran out back for a bit. Way different engine. Had to readjust carb and it was acting very nice for a change. The true test will be tomorrow at the track. Thanks everybody for the help.

RCBOY 1 09-04-2010 01:41 PM

ok im new to rb engines just ran across a great deal on one and got it it a c6 with the Rick Brakes Mod on it does anyone know what temps it should run at if so that would be appriciated thanks

cdc 09-04-2010 01:53 PM


Originally Posted by RCBOY 1 (Post 7898376)
ok im new to rb engines just ran across a great deal on one and got it it a c6 with the Rick Brakes Mod on it does anyone know what temps it should run at if so that would be appriciated thanks

220-260


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