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Old 05-23-2010, 06:13 PM   #16
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3 gallons....flame outs galore...blown plugs by the dozen, new carb, o rings, bearings didn't help. Ran like a champ before that. It was my first motor as well.
what about the rod/sleeve and crank pin?
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Old 05-23-2010, 06:26 PM   #17
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5 gallons for me and cracked the case in my last race.My first nitro race motor everything else is fine so i ordered a new case and will see how it goes. Cheaper then buying a new engine.
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Old 05-23-2010, 06:42 PM   #18
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i think the vspec is great motor if you know what u r doing with the motor since they are a compresion motor meaning not alot of factory metal pinch like the nova motors they are very touchy to break in right if broke in wrong dont seem to last long at all also is good idea to change the bearings every 2or three gallons and rod they will last along time for guy who started thread sounds more like clutch spring or clutch shoe issue then anything else check all that stuff will cause flame outs as will leaky front bearing although that usually causes erratic tuning which you asy you didnt have so would check the clutch stuff and check for carb air leak that is also common with these motors
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Old 05-23-2010, 07:22 PM   #19
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thanks for all the posts guys. sealed the engine up and inspected. replaced all the clutch parts and will give it another go. By the way, i used the heat cycle method to break it in...
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Old 05-23-2010, 08:00 PM   #20
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I ran 6 tanks through mine before the front bearing started leaking like a faucet. I have TKO's on the way so hopefully that will cure it and i can get it back in the buggy.
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Old 05-23-2010, 08:01 PM   #21
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I ran 6 tanks through mine before the front bearing started leaking like a faucet. I have TKO's on the way so hopefully that will cure it and i can get it back in the buggy.
that is pretty unusual. Must of got a bad one.
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Old 05-23-2010, 08:06 PM   #22
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that is pretty unusual. Must of got a bad one.
Yeah, i had heard the 2008 models had some bearing issues. Oh well, good excuse to put in the ceramics.
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Old 05-24-2010, 04:31 AM   #23
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Lior, considerin the condition due to age, perhaps your chassis has something to do with it if there is a rash of case issues.

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Old 05-24-2010, 07:50 AM   #24
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I just went through my 7th gallon of fuel on this engine, I still have compression and I ran ALL weekend and it flamed once, think a rock or something got caught in there.
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Old 05-24-2010, 08:05 AM   #25
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I only got a gallon out of mine. Lost all compression and wouldnt hold a tune at all
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Old 05-24-2010, 12:48 PM   #26
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i have a mugen ninja that running stong at a gallon, it hasnt dropped its nuts yet.
And what is this engine? OS.

All of my Vspec's, 3 normals, and 2 speed's have had over 8 gallons when I have sold them and still going. OS engines lose that typical mechanical pinch very fast but have power, and run strong for a very long time. V Spec was, and still is the most popular engine in my area and I have seen two failures that I would call premature. I bet that's 140-150 V Spec's.
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Old 05-24-2010, 02:30 PM   #27
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Mine never even had pinch from the get go. After about 1 gallon it would not even stay running.
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Old 05-24-2010, 03:37 PM   #28
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it hasnt dropped its nuts yet.
that's funny!
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Old 05-26-2010, 07:51 PM   #29
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I ran 6 tanks through mine before the front bearing started leaking like a faucet. I have TKO's on the way so hopefully that will cure it and i can get it back in the buggy.
I've been trying to wrap my head around this. Why does this happen? I mean, it's not like the bearing actually is a seal to start with. The crank fits so tightly in the case that the oil-buildup makes the seal. You can tun a engine with a metal, or Teflon seal. (Heck, due to lack of other i've run boat, and airplane engines with unsealed front bearings)

I have a theory. (i haven't been here long enough for you guys to get to know this about me, but i almost always have, when i start asking questions)
It goes a bit like this. When a bearing has to much play, the crank misaligns, making the oil-buildup not seal properly, and hence it leaks. Due to this i always check crankcases for damage when i replace the bearings.
I've seen engines that have had the front bearing only replaced, since it was there it leaked, but soon they started leaking again, or had catastrophic failures.

Anyone else cares to share a thought on this issue? Perhaps I'm out of line developing my line of thought here, and if so I'm sorry.

More on topic. I've run at least 35 liters through my training wheels... Sorry, my practice V-spec. It's easier to start then it was when it was new, but still goes like it's chased by a hungry demon. It's a screamer, i like it so much i bought a second hand one for practice backup, and spent more then a new one costs to "make it better".
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Old 05-26-2010, 08:05 PM   #30
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I've been trying to wrap my head around this. Why does this happen? I mean, it's not like the bearing actually is a seal to start with. The crank fits so tightly in the case that the oil-buildup makes the seal. You can tun a engine with a metal, or Teflon seal. (Heck, due to lack of other i've run boat, and airplane engines with unsealed front bearings)

I have a theory. (i haven't been here long enough for you guys to get to know this about me, but i almost always have, when i start asking questions)
It goes a bit like this. When a bearing has to much play, the crank misaligns, making the oil-buildup not seal properly, and hence it leaks. Due to this i always check crankcases for damage when i replace the bearings.
I've seen engines that have had the front bearing only replaced, since it was there it leaked, but soon they started leaking again, or had catastrophic failures.

Anyone else cares to share a thought on this issue? Perhaps I'm out of line developing my line of thought here, and if so I'm sorry.

More on topic. I've run at least 35 liters through my training wheels... Sorry, my practice V-spec. It's easier to start then it was when it was new, but still goes like it's chased by a hungry demon. It's a screamer, i like it so much i bought a second hand one for practice backup, and spent more then a new one costs to "make it better".
B!
that is very true. if you have any trouble whatsoever sliding the crank through, the bearings are not seated properly. And yes, failure is a coming
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