5LikesNEW OS 21 XZ-B and Speed XZ-B
07-06-2012, 10:59 PM
#3511
I purchased a O.S. .21 xz-b about a month ago. Followed O.S.'s break in procedure as dedcribed in there manual. (Also want to share that i am not new to nitro buggy) The break in went flawless.. And the motor ran strong through the first gallon.... I alway monitored tempature ( even though i never used it as a tuning aid. I went by smoke stream) kept it right around the 240 range. Engine ran strong around that temp range. Anyways, to make a long story short. The engine started to loose pinch after the first gallon pretty rapidly. Also, obviously was tuff to get a consistent tune out of with the reduced pinch. Well i sent the engine to rcrenew ( Out of disbelief that i was sending a engine in with a gallon and a half through it. Lance called me and told me the crank journal is wore, front bearing is trashed, and also rear bearing!! Has anyone else had issues like this? I just wanted to get my story out here to let people no. Thanks guys. -Tim
Yep, pretty much had the same thing happen. I'm not very impressed with the XZ line. The VZ line was a better engine. Revved higher and ran better overall.
07-06-2012, 11:05 PM
#3512
I purchased a O.S. .21 xz-b about a month ago. Followed O.S.'s break in procedure as dedcribed in there manual. (Also want to share that i am not new to nitro buggy) The break in went flawless.. And the motor ran strong through the first gallon.... I alway monitored tempature ( even though i never used it as a tuning aid. I went by smoke stream) kept it right around the 240 range. Engine ran strong around that temp range. Anyways, to make a long story short. The engine started to loose pinch after the first gallon pretty rapidly. Also, obviously was tuff to get a consistent tune out of with the reduced pinch. Well i sent the engine to rcrenew ( Out of disbelief that i was sending a engine in with a gallon and a half through it. Lance called me and told me the crank journal is wore, front bearing is trashed, and also rear bearing!! Has anyone else had issues like this? I just wanted to get my story out here to let people no. Thanks guys. -Tim
What type of fuel are you burning.
07-06-2012, 11:12 PM
#3513
Having a mill go out within two gallon isn't normal having to rebuild a fairly new mill isnt normal for any brand something isn't right or something was done incorrectly. I could live with it lost its pinch because people don't understand how to properly run in a mill but for him to do a complete overall is weird.
07-06-2012, 11:34 PM
#3514
I purchased a O.S. .21 xz-b about a month ago. Followed O.S.'s break in procedure as dedcribed in there manual. (Also want to share that i am not new to nitro buggy) The break in went flawless.. And the motor ran strong through the first gallon.... I alway monitored tempature ( even though i never used it as a tuning aid. I went by smoke stream) kept it right around the 240 range. Engine ran strong around that temp range. Anyways, to make a long story short. The engine started to loose pinch after the first gallon pretty rapidly. Also, obviously was tuff to get a consistent tune out of with the reduced pinch. Well i sent the engine to rcrenew ( Out of disbelief that i was sending a engine in with a gallon and a half through it. Lance called me and told me the crank journal is wore, front bearing is trashed, and also rear bearing!! Has anyone else had issues like this? I just wanted to get my story out here to let people no. Thanks guys. -Tim
Either one of the bearings going bad after a few gallons isn't uncommon. One gallon is.
What other engines have you had before this? Most people don't realize how little compression these engines have (meaning, compared to others) once they are past break-in.
Now as for the "followed O.S.' break-in prcedure as described in their manual"... if you truly did follow this verbatum, then that is why your engine failed. It essentially says start the motor cold (no mention of preheating), then immediately start revving the engine to warm it up, and the first tank should be while driving around the track at a rich setting (which would never keep the engine above 170F), while leaning it out top end....
07-07-2012, 07:30 PM
#3515
Hey guys, just noticed my front bearing is starting to leak. Im around the 3 gallon mark on my speed. What would be a good set of replacement bearings? I've had novas in the past, and always used the double seal nova front bearings. Anyone using ceramics in the front?
07-07-2012, 08:11 PM
#3516
It's funny how all racers have either a love or hate relationship with OS engines. It's like 50% love them and 50% hate them. There doesn't seem to be any in-betweeners. I guess that can be said about allot of brands but it's always OS in the limelight.
07-07-2012, 08:18 PM
#3517
Are you flaming out are you have tuning issues
07-07-2012, 08:21 PM
#3518
It seems that way for alot of different brands, but os does get it the worse. I think alot of it has to do with the price and the end user. If some one pays upwards of 500 bucks for a motor, and then proceeds to neglect maintenance on it, and only gets a few gallons out of it before its a paperweight, then they have a sour taste for os. I've had good luck with mine so far, but its my first os speed. Basic stuff like bearings and maybe a pinch are to be expected.
07-07-2012, 11:09 PM
#3521
07-07-2012, 11:45 PM
#3522
Well I have a gallon and a half or so through my os speed now, runs like a raped ape and temps are always under 250 now, BUT I had three flame outs in the main tonight and im barely getting 7 minutes per tank in buggy with a 2090 pipe. Wtf is going on with this thing? Did its balls just drop or what? The flywheel is pretty easy to turn over when it's hot, the idle is solid as well. Whst should I check?
Last edited by B00t13g; 07-08-2012 at 09:53 AM.
07-08-2012, 01:44 AM
#3523
Tech Master
iTrader: (16)
TKO ceramic bearings front and rear, never had a problem with them ever. Plus they helped OS solve their bearing problems a few years ago (but looks like OS might again be having bearing problems? I always install TKO ceramics before break-in and don't waste my time with whatever OS installs at the factory) so get yourself some TKO ceramics and you won't regret it.
07-08-2012, 03:56 AM
#3524
Tech Adept
Hi Aaron, can I ask how do you go about changing these bearings? Is there any guide available some where? This being my first attempt 
TKO ceramic bearings front and rear, never had a problem with them ever. Plus they helped OS solve their bearing problems a few years ago (but looks like OS might again be having bearing problems? I always install TKO ceramics before break-in and don't waste my time with whatever OS installs at the factory) so get yourself some TKO ceramics and you won't regret it.