I just got my LST this morning and after a quick comparison with the Savage, this thing is a monster!! I love the overall fit and finish with it, i can tell it'll be a great truck. I checked the needles to find they were way off from what they said in the manual and fixed them both.

So this afternoon after rebuilding my savage diffs I decided I may as well go break it in. Primed it till fuel reached the carb and stopped. Put my glow igniter on top and gave it a short rasp of the electric starter and it fired right up. It sat there idling as I started to bump up the throttle trim to get it to idle at a bit higher speed set for break-in. As I neared 20 on the throttle trim and about 10 seconds into starting it it shut off. Just died, no change in sound or rpm just off. Throttle must still be too low so I bumped it up a little bit more, put the truck on some blocks to elevate the wheels and started it up again. Started on first squeeze and ran for 7 seconds before the same thing. K, now I'm very confused, this has never happened to me before on break-in. After one more stall it became harder to turn over so I stopped, turned off the radio and headed inside to figure out what is wrong. The fuel tubing looks good, no air bubbles, no change in engine speed before cutting out.

Is my engine defective? Might a call to Losi tech support be in order? I might give them a call while it's still the afternoon, I'd really have liked this to get off to a better start. It looks like a god truck.

You shouldn't use the throttle trim to control the idle speed because as soon as you hit the brakes the engine will die. Additionally with the stock needle settings the engine will not idle for long without the glow ignitor attached. If I were you I would lean the low end a little bit, increase the idle speed with the idle screw, and start the engine and drive it immediately. I am not a big fan of idling through a few tanks for break-in as far as I am concerned the engine runs too cold. I like to get the model started and run it at 170 degrees for break-in making sure never exceeding 1/2 throttle or overheating the engine.

Chris

Sounds like it may be running rich and flaming out your plug. Lean it out an hour or two and keep plugging away.

Another thing to check, make sure your fuel filter isn't hitting the cooling head. Could be causing glitching which could make the throttle servo twitch and flameout your engine. I bought some fuel tubing to re-locate the filter to the side of the fuel tank.

Beat me to the punch Chris...and a better explanation to boot.

Cool, thanks for the fast response, I thought about adjusting the low end but wasn't sure.

And the fuel filter is practically part of the cooling head it's so close, it's the factory setup but I'll try to reposition it. Thanks again, I'll give it a go.

nothing gives.

It does the exact same thing, dying after a few seconds. I can't believe this is the only RC vehicle I've read the manual for and the only one I've had troubles with on break in even! Definitely not a good sign but I'll try to ignore that for the time being.

Instead of trying to get it to idle I'm trying to get it to run now, the engine shuts down after I apply slight pressure to the throttle to try to drive it around. It seems completely flooded so i took out the glowplug, replaced the batts in my igniter and charged the electric start again. Gonna try it with a fresh start, maybe a new plug too if I can find one the right temp. I checked and re-checked the needles, 3.5 on the high and 2 on the low as stated in the manual. Leaning the low end out did nothing nor did leaning the high end.

If I can't come to any sane conclusion about this engine I may just ebay it before i end up wrecking it during break in. [:@] I'll see if my Nitro Star S-25 fits with an easy enough mod, it's a very new truck still so I'm sure there's not much info floating around on engine swaps yet. Why is HPI the only company that ships their trucks with good motors stock.

I mean I love Losi and this truck looks great everywhere else but this just further supports my claims about not buying Dynamite products, they've always seemed sub-par to me. It's not like Losi to do that on a $600 truck but for such excellent stock parts including a $200 radio system, you have to make a compromise somewhere and this engine looks like the place. For example, what's with the metal carb? A lightweight composite one as found on the S-25 should be stock equipment. The other money "outlet" seems to be the electric start, and while i haven't had any troubles with it yet (other than it wrenching out of my hand a few times because of it's awkward shape) it feels cheap and flimsy in my hand. Quite unlike the feel of the HPI roto-start which I wish could fit the hex shaft of my kickin' new LST. I've heard of at least one person having their starter stop working too.


My truck is number 660, maybe its the devil truck minus the last 6, i dunno but it better stop acting up or a call to Losi may be in order. (then to the dealer and finally UPS if you get my drift )

Factory needle settings are only a safe starting point. They do not take into consideration weather, nitro content, glo plug, et. With that said, post your glo plug, fuel, etc. It sounds like you are just super rich on the low end. Lean it a bit, turn the idle up, and start it again. Once its up and running, adjust the low speed needle so you are spitting some oil out that pipe at idle. You will have to adjust idle during this time. Once you have some decent running settings, keep the idle high, but you dont have to have it so the clutches are engaging all the time. I wouldnt break any motor in at under 180. Good luck! Keep us posted.

Matt

I'm using the stock plug, or an MC-59 which is recommended for break in. I'm running Maxy's 20% nitro, the same I use in my Savage 25, Maximum MT and nitro MT2.

As for spiting fuel out, well does gushing count? I literally now have a puddle I have to clean up. Great.

First of all...RELAX! LOL
It sounds like it could be a glow plug issue. I've had similar problems, and it was as simple as that.
Will it keep running if you leave the igniter in?

You are extremely rich man. Lean out your LSN a 1/4 turn. Let it warm up then check temps. Tap the gas and see if it stalls. If it still stalls and the engine is around 170, lean the LSN another 1/4 turn. Its just running really rich.

Matt

Don't give up on this engine, it is VERY good. Once you have the needles set properly it will idle for ever, accelerate quickly and run cool. If the engine is spitting fuel out when it is idling the low speed adjustment is not 2 turns out, it has to be a lot more. Is the carb completely closed when you are checking the low speed adjustment as it says in the manual? Depending how it stalls when you increase the throttle will tell you if the high end is lean or rich. If it dies without any increase in rpm it is flooding and the high end is rich. If it sounds "thin" and the rpms increase sharply before it dies the high speed is lean. Maybe you can take it back where you bought it and ask them for help? Where are you in Florida? Hydro-locking of the engine is a sure sign that the low speed needle is to rich.

Chris

Also, did you return the throttle trim?

Thanks guys for helping CreyC out...I've been tied up around here at work. If you are still having problems, please call our customer support guy Bill. He'll help you out. 909-390-9595 .... I know I know, it's not toll free, but I'm working on that LOL

Good catch evil e, I got it back to normal about halfway into the tank when I noticed it would slow down when braking. It seems to be running great now and I'm on my 6th tank, haven't even tried to tune for speed yet, heck I haven't even played around in 4WD high yet. I'm starting to get some really nice wheelies, there is definitely a lot of power for that in first gear.

One question I had about it was in low going down a straight away it won't shift to second. The engine is *****g out RPM wise but I realize that because the 2nd speed clutch is on the spur gear the gear ratio is not aggressive enough to get the clutch up to speed to shift. Is this normal? Or did it already shift and I didn't notice because it happened so fast?

I'll post some videos as soon as my brother gets back to hold the camera. Thanks for the help everyone!

You might want to check for leaks. What I found on my MACH .26 engine during the first 2 tanks of breaking in was that the Hi Speed needle fitting was loose. Dont actually dont know what the actual part name on the carb is called, but its the bronze fitting where the fuel line is connected right where the throttle spring is hooked on to. I was spilling fuel all over the truck and thought I was just running rich, but was actually the Hi Spd needle casing just being loose. Try tightening that up. Might also be a good idea to pull off the engine and do an overall inspection and tightening. Check all fuel lines, screws, carb neck tightness, etc. I would go as far as tearing down the whole engine if the problem persists. A few years ago, I once had a brand new, never started Dynamite .12 TNT engine where I had this same problem as creyc. After 2 hours of trying to start the engine I finally got frustrated and decided to tear down the engine. As I took the cooling head off I noticed that the piston had a pin sized hole going straight down the piston head. The engine had enough compression to start but after a 2 seconds, then just die out. Don't want to knock on Dynamite engines, but just had weird luck with them, thats all. Hope this helps your quest on getting that engine to run like you want it to.

whoops. I guess you got to run before I posted. But now on to your shifting problem, I noticed that when I am in Low gear, its shifts so fast you cant really notice it shifting or hearing it shift. Also you might just have to adjust your set screws in the 2SPD tranny.

Yep, it's running great now, good temperatures and a trail of smoke so it seems everything is running as it should.


One other thing I wondered was how well it's supposed to be able to pull wheelies. And I know how bad this will look to people that didn't read this thread thinking some crazy guy's trying to do wheelies on break in but I've got about 8 tanks through it so I'm done with all that. It'll pull the front tires up in the air in low gear, actually if I'm stopped in the grass it can flip the truck right over on it's back! Quite a lot of power really for a 13lb truck.

In high speed however it doesn't have as much torque, the front end lifts and uncompresses the sag of the suspension but the tires never leave the ground. Is this normal? I know high speed is a very much higher gear ratio than low and the tires are much larger and heavier than my Savage tires for instance but I just want to make sure my truck is performing as it should.

Does that seem about the same as your LST? Also I haven't cut any holes out of the body because I feel that shouldn't be necessary, if Losi felt that was a problem they surely would have done that from the factory. Besides there's a huge channel near the front wheel wells where tons of air blows through so cutting holes shouldn't be necessary.

mine ran way better with the hole in the windshield