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Old 03-06-2009, 06:18 PM   #1
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Default Help with XXXNT..

Losi Support sucks, so I've decided to come online because they close on weekends

My Roto-Start works great when the engine is cold, but as soon as it's up to operating temperatures, it goes whack and works very sporadically. I was told it was the One-Way bearing. I've ran this truck maybe 5-6 times, 2 times racing.

Also, I just took it out, and the engine runs great for around 3-4 minutes, but then it starts to want to die if you give it any throttle. Dies at WOT. Doesn't matter if I go slowly on the throttle or fast, dies. I've turned the Top End 1/2 a turn clockwise and it didn't fix it, any help?

I'm about to give up on this thing and sell it. Ever since I've bought it's been nothing but trouble, haven't had ANY enjoyment out of it yet.
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Old 03-06-2009, 10:20 PM   #2
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Quote:
Originally Posted by Error404 View Post
Losi Support sucks, so I've decided to come online because they close on weekends

My Roto-Start works great when the engine is cold, but as soon as it's up to operating temperatures, it goes whack and works very sporadically. I was told it was the One-Way bearing. I've ran this truck maybe 5-6 times, 2 times racing.

Also, I just took it out, and the engine runs great for around 3-4 minutes, but then it starts to want to die if you give it any throttle. Dies at WOT. Doesn't matter if I go slowly on the throttle or fast, dies. I've turned the Top End 1/2 a turn clockwise and it didn't fix it, any help?

I'm about to give up on this thing and sell it. Ever since I've bought it's been nothing but trouble, haven't had ANY enjoyment out of it yet.
Nitro blue's, we've all been there at one point. The one-way sounds like the problem. 1.You can take it out and clean it really good with motor spray to see if it helps catch the crankshaft. 2. Change the glow plug, that should be checked or replaced regularly. Set the high/low screws back to factory settings and retune or have someone at your LHS help with this. 3. I know it's not fun now with the troubles your having but once everythings working together, it's most enjoyable. Good luck and dont give up.
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Old 03-06-2009, 11:08 PM   #3
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I have to agree with everything the Dude said. It's a good idea to find a local racer that can help teach you to tune and troubleshoot your engine. Also if you change glow plugs, you need to make sure you get the right kind. You want a standard long plug that's rated "HOT".
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Old 03-07-2009, 11:05 AM   #4
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Thanks for the help guys.

I took apart my RotoStart from the engine and soaked the One Way bearing in Denatured Alcohol and cleaned all the other parts, they seemed to have a bunch of oil on them, and then cleaned it with greased lightning hopefully this helps.

Any tips on Glow Plugs? This is a brand new glow plug with maybe 2 tanks on it. I replaced the stock Glow Plug for a McCoy MC-55, I bought 3-4 just in case, now I have to find the brand new ones.

Again, thanks for the help, sometimes it's really frustrating especially when my first race I posted the fastest lap, was first and my spur decided to strip on me.
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Old 03-07-2009, 12:20 PM   #5
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I'm not famialiar with the MC-55 plugs. However I love the MC-59 plugs for that size engine.

It's best to only use a very light oil, or none at all, on the one-way bearing. The thick oil comes from the fuel. It leaks through the backplate and as the alchohol evaporates it leaves the thick oil behind. One trick is to drill a small hole in the plastic starter housing where you can insert the tube from a can of nitro cleaner pointed at the one-way bearing. You also need to drill a small drain hole in the bottom so the crud can get out.

I realy enjoy the XXX-NT trucks. Once you get to know it a little more, I'm sure you'll really like it. There are a few up-grades you can do to it to make it more reliable. Also setting the diff and slipper is very critical. Once you get the diff set it should be trouble free. It's a good idea to check the slipper regularly, but they rarely need more than a slight adjustment. clutch bearings are the one item that needs the most attention. Other than that they can run for several gallons without hardly any maintainance other than crash damage.

The roto-start and pull-start engines add a little frustration. A starter box is a nice thing to have.
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Old 03-07-2009, 01:00 PM   #6
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Quote:
It's best to only use a very light oil, or none at all, on the one-way bearing. The thick oil comes from the fuel. It leaks through the backplate and as the alchohol evaporates it leaves the thick oil behind.
I cleaned it and soaked it in Greased Lightning so hopefully that broke the thick oil up, it's what I used on my chassis when I cleaned it and it broke the fuel oil down and I could just wash it off.

Quote:
Also setting the diff and slipper is very critical. Once you get the diff set it should be trouble free. It's a good idea to check the slipper regularly, but they rarely need more than a slight adjustment.
After stripping the spur twice, I called Losi and sent it to Gary, and it was rebuilt by one of the pro guys, I mentioned I raced it at Revelations and was told that's where they tested it and set it up, so I went there for a practice and it stripped again. I sent it back again and I haven't had the chance to try it at Revelations, although I'm thinking I'm just having bad luck at Revelations.

I bought a metal spur gear since I heard good things about it but then was told by a local racer to just use the stock plastic one so it was like money down the drain.

Quote:
A starter box is a nice thing to have.
I've been meaning to get one, but Losi sell's em for 75 bucks which I don't want to spend so I've been looking for a used one, hopefully I can pick one up and get rid of this Rotostart.
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Old 03-07-2009, 05:11 PM   #7
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I'm tired of this truck. Nothing but problems. Not spending 13 dollars for a one way bearing thats going to keep going out. This is bulls**t. Spend 300 dollars and can't even get to enjoy the damn thing.
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Old 03-25-2009, 11:52 AM   #8
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Found a temporary fix:
High temp silicone. It's the red stuff from AutoZone. Put it at the end of the of the one way over the opening and the shaft. Able to do a good 4-5 tanks out of it without having an issue.
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