New engine running wierdly?

[joshiestevens]

Hi. I have started my kyosho tr-15 stadium force to break in. It runs for a few mins, and then it jerks abit (like you are moving the throttle slightly, then stalls) Also after 1min of idling, the engine head around glow plug smokes. (I think thats just excess oil). At first huge amounts of oil were litterally dripping from the exhast, but I have leaned it a little. There is still small bits of brown oil coming in the tube from the tank to the exhaust. I don't know how to stop it stalling. (Is it something to do with the LSN)

Josh

 

[Error401]

Is there a fuel filter on the intake line? Sounds to me like there some crap in the HSN and it's running way too lean. Engines shouldn't smoke around the plug and the decreased ammount of exhaust oil is kind of a warning.

 

[joshiestevens]

No there isnt. The only place where there is that brown oil, is the tube that connects from the gas tank straight into the exhaust.

Isnt it running rich (isnt that why its spitting), and its almost like there is so much fuel that its leaking out around the glow plug?

It stalls after a few mins. Also, when I did lean it, less oil spit from the exhaust.

 

[Error401]

After about a minute of idling, nothing on the engine or the pipe should be smoking. If it oil that is smoking, then it is definately running way too hot. There should be smoke comming out of the exhaust, but not the head.

Believe me, fuel isn't filtered unless you put a filter on the line. It doesn't take alot to clog the high speed needle and make it run lean. Even though it is a high speed needle, it does regulate the overall fuel intake and the low speed needle is dependant on the HSN, not the other way around. Install a fuel filter.

The brown oil comming from the pipe to the tank is normal. This is the tank pressure line. It will always have some oil in it.

If you don't have a temperature gun, get one. There are some other members here that are located in England and can suggest places to get one. For the best results, tune by temperature. I'd hit Shorty up with a PM, I think he found one over there.

 

[joshiestevens]

For some reason, the engine head smoked on my last trck which was rtr. How tight should the glow plug be. Also, should I adjust the HSN when the engine is running, and how will I know when it is perfect. Also, do you think I am damaging my engine?

 

[Error401]

First, do not overtighten the plug. Snug to pretty snug is fine, but do not crank down on it. Be sure that the copper washer is under the plug also.

It's really kind of hard to say about whether you are damaging the engine by running hot. Yes, running it lean (plug temp above 300 degrees f) will damage most engines. I'm not saying that you are, but it kind of sounds like it's running hot (lean) by what you described. Engines will generally run, increase rpm and die when they get hot. generally, when set to slobbering rich, they will pretty much keep idling till the run out of fuel. There have been numerous threads on engine tuning located on this site. Without getting lengthy and recovering old ground, I'd run a search with the key words "pinch test" and "engine tuning". That should get you enough info to at least get your mill to idle fairly reliably.

Also, I would clean out the HSN assembly and install a fuel filter (going to the carb from the tank). If you have yet to disassemble a HSN, let me know before you take it apart (there are some important things to note before you disassemble the HSN).

One other thing to check is the head bolt tightness. Again, make sure they are fairly sung, but not loose or over tight. The head bolts will work their way loose if not checked from time to time.

 

[joshiestevens]

I really do not want to take apart the HSN. Becasue its a new engine, I think its fine, and I am sure i dont need a filter. What I am going to do though, is to check how rich or lean it is.

How much oil should spit from the exhaust when its rich or lean, and what sort of sound should the engine make when idling rich or lean.

The thing is, oil still spits from the exhaust, so I thought that it is rich. If after running and the engine has cooled off, I pck p he car and shake it on its side, a small amount of brown oil drips out.

Also, Wont the engine head be leaking oil if it is running rich, because there is too much fuel, and it wants to get out.

Josh

 

[Error401]

All I can do is offer advice.

If it's running as rich as it should during breakin, there should be alot of oil that comes out of the pipe. Ideally, there should be a sizeable oil patch on the ground from it idling, and when you tip it (after it's done running) a fair ammount should run out of the pipe.

But it's your engine and your call as to what to do. Good luck.

 

[joshiestevens]

ok. Do you think I should try factory settings again. 4 turns from closed. p.s - how do u know when its a full turn?

Should it be stalling after a few mins. I hear it jumping around a few mins. Its not a steady idling noise, and then it dies down abit, so I rev it up, and then I leave it, and it dies down slowly?

Josh

I could try and make a video of it, and post it?

 

[Error401]

Factory settings are a good place to start. to return the needles to factory, you will have to screw them in (very carefully) until they just barely seat. Do not put any torque on them after they bottom out. Note the position or alignment of the slot. Then unscrew them to the factory recommended number of turns. If there is a mid range needle on the carb, do not touch it, ever.

Usually when an engine slowly looses RPM during idle it means that the LSN and HSN are set rich and the crank case is loading up with unburnt fuel. When you say it's not steady, do you mean it sounds like it's missing every now and then? If so, that's another indication that it's rich and is doing what's called 4-stroking.

What kind of bothers me is the smoking it's doing around the plug and head. Look for cooked oil buildup in the areas that it's smoking. If there is oil leaking somewhere it will usually cook down and leave a glaze. But it has to get pretty hot to start smoking.

 

[joshiestevens]

I wont change anything just yet, but I will record a 3minute close up video of the car, from starting to to stalling it, so you can hear, and see the smoke etc?

Josh

 

[olds97_lss]

That would probably help with a diagnosis.

Do you have a temp gun yet? Knowing what the temps are would help as well. Judging rich/lean settings only on the amount of oil coming out of the pipe isn't real accurate.

 

[joshiestevens]

Hi. I recorded 2, 1 min videos. The first on is the car running. And when I talk about smoke in the second video, I am talking abut the engine head, but this time it didnt smoke because it cut off too early.

http://www.getfreegadgets.co.uk/car1.avi
http://www.getfreegadgets.co.uk/car2.avi

Thanks for your help
Josh

 

[olds97_lss]

How many tanks have you run through it so far? I'd richen the low and high end adj about 1/8 turn and let it run like you had it in the first vid. Where the tires were spinning.

Personaly, I drive it when I'm breaking it in. That way, the rpm's don't get away from you like they do with the tires spinning freely in the air.

If you do drive it, drive it on a smooth hard surface while breaking it in to lesson the load on the engine. When your breaking an engine in, they are almost always tempermental due to the engine not being fully worn in. While driving, blip the throttle to about 1/2 periodically to keep the engine from loading up.

Just keep an eye on the head temps as best as you can. Get something that you can use to put a few drops of water on the top fin of the head. It should take 3-4 seconds to sizzle off. If the water drop jumps off instantly, it's to hot. If it sits on there and takes more than 6 seconds or so, its too cool.

You adjust the mixture screws to adjust the head temp. When your only opening the throttle to 1/2, the majority of the setting is on the low speed needle. Make sure the high speed needle is rich enough to allow enough fuel flow as well, but worry about adjusting it right after you get 4 or 5 tanks through the engine.

 

[joshiestevens]

Did you watch the video, and you think I should richen up the LSN abit.

Also, what do you mean

"While driving, blip the throttle to about 1/2 periodically to keep the engine from loading up. "

That was basically the beinning of my second tank. I filled up the 1st tank when it was a 1/5 full.

Do you think the best way to break it in, is how the instructions say it, or another way?

josh

 

[olds97_lss]

I've just never had good luck doing break in with the wheels off the ground. With as rich as you need it for breakin, you need to give it throttle often. This makes the whole drive train scream if it's off the ground. By having it on the ground, it allows you to coltrol the throttle more easily.

The reason I say richen it, is because you said it got hot (head smoking) and died. If you've already richened it after that, then you should be ok.

Everyone has their own way of breaking an engine in. I have my way, the mfr has their way. I like to get the engine temp up as soon as possible to avoid early wear on the piston and sleeve. Then in between tanks, I make sure the piston is at the bottom of the stroke while it cools.

It's worked well for me.

 

[joshiestevens]

I havent adjusted the carb since that video. What does it look like it needs doing. Also, did you see when I showed all the stuff that spat out the exhaust. Rich or lean, and also how do u make sure he piston sleeve is at the bottom, and why is it better?

 

[olds97_lss]

By putting the piston at the bottom of the stroke while it cools, it allows the sleeve to shrink correctly. It supposedly helps prolong engine life.

I did it on one of my engines every time I shut it down, not just break in, and it still had decent compression after 7 gallons was run through it over the course of a year. I sold the truck with the engine in it, so I don't know how long it lasted after that.

Needless to say, I do it on every engine I run now. It's easier if you mark the flywheel so you know when the piston is at BDC (bottom dead center/bottom of stroke) without taking the glow plug out ever tank to look.

I just put a dot of fingernail polish on the flywheel.

 

[SlingItX]

Videos

Based on what's in the videos it seems to be 'loading up' from running too rich. Typical during break-in if you're not blipping the throttle a little to blow some excess fuel through, this will happen. In other words, too much fuel is going in while it's idling and not getting 'burnt off'. Another good indication is that you can touch the head and it 'appears to be warm'. You really need to get the temp up a little more to heat cycle it during break-in.

Don't be afraid to blip the throttle some during break-in - I personally don't subscribe to the theory that you should idle through several tanks for break-in. Because the needle settings are so rich the engine rarely reaches heat-cycling temps.

Take olds97_lss' advice and run it a bit on the ground blipping the throttle on occasion.

The oil and fuel spewing from the exhaust is perfectly normal when you're running so rich. As a matter of fact, it seems a bit on the lighter side, as olds97_lss has suggested.

-SlingItX

 

[joshiestevens]

I riched both needles out an 1/8. I put it on the ground, and ran it at about 0.5mph. When I slowly accelerated, the engine died and then stalled?