Help with TT PRO .21engine

[Ericke1]

Help with TT PRO .21 engine

I recently took out of storage my Thunder Tiger Mirage VSpec with the TT Pro .21 engine. I started it up that day with no problems and then squeezed the fuel tubing to turn off the engine. Last night I restarted the engine, it roared on, then it started running by itself fast and faster. I checked the carb needle it was closed tight, even applied the brakes to make sure the servo was closed (adjusted the needles on my remote and pushed the servo rods to shut the carb as much as possible) but it just kept getting faster and faster. I even saw a little smoke come out of the engine header but it went away. If I loosen the carb screw anymore, it might fall off. I had to squeeze the fuel tubing to turn off the car. Whats wrong? Is it too lean?

:burp::fro:

 

[jon2]

Ok check the head to make sure that the head is on right and tight. I have the same engine in m MGT and found they are notorious for leaks. Use RTV silicone to seal the carb and the backplate. Don't get too much but just smear enough. ALso what Plug are ou using? Team AE recommended that we use short plug but Long plugs are the way to go. Good luck and let me know what happens

 

[Ericke1]

I use an OS 8 plug, but if the car starts properly, I dont think the plug would make a difference right? Ill check the head today too.

 

[jon2]

The plug still works but for optimal performance from your Mill I would recommend the Long plug. I am not sure if the OS8 is long as I use Mcoy plugs and Duratrax plugs.

 

[cbreaker]

Glowplugs can affect performance across the entire spectrum.

They not only glow when the glow igniter is on them to help start the motor, but they glow while the engine is running as well, without the igniter. As the fuel explodes, the coil heats up and glows to help the combustion process by providing a little extra heat so that the gas explodes properly.

I haven't been in this hobby for very long and I've already seen all sorts of weird problems caused by glowplug funkyness. My friends' Force 26 would lose power on the high end and stall out, but with a new glowplug and minimal extra tuning it ran great (no matter what we did before the new plug, it died.) My friends' Novarossi engine had a problem that was exasperated by a bad glowplug.

If the engine is tuned correctly, you can run the same plug for a long time. But all it can take to foul them sometimes is a tank on a too rich or too lean situation.

 

[Ericke1]

The glowplug is not my problem, I didnt ask about the glowplug, but about the engine not staying idle.

 

[jon2]

Ok well then didi you set your Transmitter properly as the Manual said to? Did you also set your HSN then your LSN and then readjust your ISS after? I had to reset my needles a few times to find out I had been tuning with a bunch of leaks. Sorry to get the thread lost in translation.

 

[cbreaker]

Originally posted by Ericke1
The glowplug is not my problem, I didnt ask about the glowplug, but about the engine not staying idle.

Your engine/idle/*whatever* is not my problem, I didn't ask to be critisized for trying to help.

If you're looking for the "magic bullet" answer to solve all your problems, you won't find it anywhere. All we can do is provide suggestions. If you're not willing to accept suggestions, then I don't know what to tell you.

You asked why your engine was running crappy at idle, and you didn't seem to understand glow plugs:

but if the car starts properly, I dont think the plug would make a difference right?

That was you. I was simply trying to help you understand the role of a glowplug in an engine, and how it can affect everything, which includes idle. I don't think that the plug would make the idle speed up like that, but I've seen some pretty crazy things happen because of them and I think that if you've tried a lot of things, it would be really silly to overlook a $4 part because "naa, that's not it." Plus, knowing how a glowplug functions could help you tune your engine in the future.

But hey, good luck with your idle...

 

[Ericke1]

Ok Sorry

Thanks for the info. I brought my engine to the LHS. He said there is a leak in the engine and I should rebuild it since air is getting in. Anyway I didnt have the time so I left it with them, they want to charge 30 bucks to rebuild so I thought ok, do you think that is the problem?

 

[ImBroken]

It most definately sounds like an air leak... When too much air is introduced, the mill will start to race up in RPM's. Almost the same way it does when you pinch off the supply of fuel to shut her down. The air to fuel ratio is key in tuning an engine, so if ones off, it will run like ass....

 

[cbreaker]

When the engine gets hot, the metal expands, which could open up the air leak more. So yea, it sounds like that nails it on the head.

If I were you, I'd save the $30 and do it myself. Really, it's easy. There's some sealant you can get, and all you have to do is seal up the head, backplate, and carb. All three things are super easy to remove and put back on, it'll probably take you 45 minutes if it's the first time. You only need a very small amount of sealant.

Plus, you'll learn a little more about the engine in doing so. They are very simple little things, and when you take them apart you can't help but think "Why did it take millions of years of evolution to come up with this?"

 

[jon2]

I could have sworn that I did post a possibility of an air leak. I am just glad you have been told by someone you trust. Now go and get some RTV silicone and have fun.

Jon

 

[Ericke1]

Thanks

Yeah Jon2, you said it was a leak, but I was able to start the car and let it idle for a while. That made me think it wasn't a leak but you were right and the dude at the store said it was. I didnt know these TT engines were that prone to leaks.

I already left the car with him, let me see if I can get it back. What sealant is available from tower that I can buy? :spit: