Fuel Leaking

[dubbiesRcs]

When I First got my Buggy (RedCat Shock Wave 1/10 scale)
We got fuel, Glowstarter and thats all... We Got it Running , did the break in Process and runned it after. I then Noticed How the Ful was Spraying on the Back Lower A-Arm On The right. (Behind the Engine) any Reason? The car is Brandnew! Also the Idle is Relly high but never changes when messing with idle screw. Please help!

 

[wwit]

Its not just excess unburned fuel coming from the exhaust? They can be kind of messy when breaking in and extra rich.

Or can you see it actually spraying? If that's the case, then go over the lines and connections carefully and look for damage or lines not connected well to fittings. Worst case, and not common on a new vehicle, unless it was damaged while running is a crack in the fuel tank. I have seen where cracks happened at the plastic boss's that the mounting screws go in to that hold the tank to the chassis.

 

[Nitrotrout]

+1 I'm pretty sure you have excess unburned fuel coming out the exhaust. That's a normal scenario during the break in process.

Idle can be lowered adjusting both the idle gap screw and the low speed needle (LSN)
Set your idle gap to the suggested factory gap and turn your LSN screw counterclockwise in very small increments if need be. Idle should be low enough to idle without stalling.
If you still can't lower the idle you may have an air leak somewhere.

Keep some extra glow plugs on hand during the break in process

 

[dubbiesRcs]

+1 I'm pretty sure you have excess unburned fuel coming out the exhaust. That's a normal scenario during the break in process.



Idle can be lowered adjusting both the idle gap screw and the low speed needle (LSN)

Set your idle gap to the suggested factory gap and turn your LSN screw counterclockwise in very small increments if need be. Idle should be low enough to idle without stalling.

If you still can't lower the idle you may have an air leak somewhere.



Keep some extra glow plugs on hand during the break in process

I did the break in process before but i think the car damaged on the way to my house take a look...

---------- Post added at 8:48 PM ---------- Previous post was at 8:47 PM ----------

Its right in the middle

 

[dubbiesRcs]

Its not just excess unburned fuel coming from the exhaust? They can be kind of messy when breaking in and extra rich.



Or can you see it actually spraying? If that's the case, then go over the lines and connections carefully and look for damage or lines not connected well to fittings. Worst case, and not common on a new vehicle, unless it was damaged while running is a crack in the fuel tank. I have seen where cracks happened at the plastic boss's that the mounting screws go in to that hold the tank to the chassis.

Redoing Zip Ties but if i Could see Where its Missing the Screw..

 

[Nitro4910]

There should only be two screws on each side holding the engine to the engine mount.
Look under the exhaust header & there on the engines mount flange you should see two of them, most likely the empty hole is to used for a
different engine or the same mount may be used across a couple different models.

 

[srusinek]

IMHO some engines will leak while running either out of the exhaust or from the bearings. It's just part of the nitro side of the hobby. No matter what fuel you run you'll also get some residue on the model but it could be curtailed some if you get a fuel with a lower oil content. For example the traxxas top fuel is a very oily fuel compared to O'Donnell and some Byrons fuels.

 

[dubbiesRcs]

Chassis subtance Please Help!

Subtance is getting every on chassis please Help..

Its getting every where... What is this shiz all over it

 

[SchrodeMode]

Looks like oil, can you tell where it's coming from? Do you have it running extra rich, what's the oil content of your fuel?

 

[wwit]

Yeah looks like nitro residue to me too. Running even a little rich can allow leftover lube to accumulate in a short time. For me, this was a bigger problem many years ago when what few LHS's in the area only carried Traxxas 20% in stock....that stuff always left a mess even when running correctly. Even the 25% Gen2 Byron's I use today that I consider high quality can leave a puddle if sitting in place.

Get a can of nitro cleaner and use that. Then just let it sit and see if anymore builds up by itself. You can try just laying a paper towel under there and see if it pin points a leak.

And a possible culprit where lots of that unburned residue collects is in the muffler in some vehicles. Then leaks out all over the place if you don't happen to catch it and dump it.

But I doubt its an engine leak problem. Any hole big enough in the engine to allow that amount of residue would be a borderline lethal problem and the engine wouldn't even start. Or if it did it wouldn't run anywhere correctly as it would suck air in causing an instant lean condition. And most likely be very noticeable.

 

[dubbiesRcs]

Yeah looks like nitro residue to me too. Running even a little rich can allow leftover lube to accumulate in a short time. For me, this was a bigger problem many years ago when what few LHS's in the area only carried Traxxas 20% in stock....that stuff always left a mess even when running correctly. Even the 25% Gen2 Byron's I use today that I consider high quality can leave a puddle if sitting in place.



Get a can of nitro cleaner and use that. Then just let it sit and see if anymore builds up by itself. You can try just laying a paper towel under there and see if it pin points a leak.



And a possible culprit where lots of that unburned residue collects is in the muffler in some vehicles. Then leaks out all over the place if you don't happen to catch it and dump it.



But I doubt its an engine leak problem. Any hole big enough in the engine to allow that amount of residue would be a borderline lethal problem and the engine wouldn't even start. Or if it did it wouldn't run anywhere correctly as it would suck air in causing an instant lean condition. And most likely be very noticeable.

If it is a Engine prob do u suggest to get a new Engine? Because its every where on the chassis.

 

[hamz9561]

First clean the chassis with the nitro cleaner or Simple Green and water making sure that it's completely dry (I recommend compressed air) then see where the oil is coming from.

 

[wwit]

If it is a Engine prob do u suggest to get a new Engine? Because its every where on the chassis.

If you have a hole in the engine, then you need to address that. Either by replacing whatever broke if parts are available or buy a new engine.

But before I went to that expense, Id make sure to narrow down the problem. No reason to spend money on a replacement engine, if its just a cracked fuel line. That's a couple bucks vs. a couple hundred. If its an actual engine problem that severe, it probably shouldn't start in the first place and even if it did, it will run like crap.

But start at square 1. And BTW, these are just suggestions from some stranger on the interwebz...so if you break it or cause harm to yourself or your RC, don't yell at me, I don't want to hear about it :

Clean it up.

Go over the fuel lines, every mm of it.

Check each fitting for cracks or broken.

Make sure the exhaust fittings are tight and that the rubber coupler is sound. Any crack here will leak. Also make sure that it is in the proper position and that its not just barely catching hold of either the manifold or pipe. And BTW, manifold can develop hairline cracks to that are hard to see until it eventually breaks completely off.

Check the entire fuel tank. Remove it if you have to, so you can inspect the mounts. These can get cracked. Make sure the fuel door is closing and sealing properly. Most have some form of adjustment to tighten if needed. Make sure all O-rings are okay and not showing damage.

If all look okay, then before I removed the engine, Id fill the tank and prime it so that the fuel lines are full of fuel. Let it just sit with paper towel or shop rag under it and keep an eye on it to see if there is any wet spots forming.

After an hour or so, Id fire it up. Is it running okay? Just let it sit at idle and watch it for leaks. Only this time make sure not to have paper towel or rags near the exhaust or engine, so they don't ignite by accident. What are the engine temps just sitting? Do you have a infrared temp gauge? If not you need one ASAP. If its running rich it will be running cold. This will cause excess fuel into the exhaust. without a temp gauge, your only guessing at this point, and most likely guessing wrong. But if it is running proper and still no leaks, then go run it in the yard for a while and keep checking it. If still nothing, then Id shut it off and let it cool down. Normally you should be removing any left over fuel out of the tank when your done running it, but for now let it sit and see if any leaks start while it cools. Keep checking for up to an hour. If nothing then drain the tank and lines.

Remove the engine and inspect all bearings, gaskets. Make sure the head is tight, but dont over tighten and strip the screws. Your most likely going to need to be able to remove the flywheel and starter assembly to inspect the bearings. Is this something you r able to do?

again, lots of 'maybe this' or 'could be that' going on. Could be its just one of the pitfalls of owning a nitro RC. They can be messy. I had 2 of the original TMaxx's when they first came out back @2000/01-ish and they both leaked like a sieve all over the chassis. In both cases it was just left over exhaust blowing out the muffler.

If you get to the point where you can't figure it out, or tearing into it is beyond your skills or comfort level, then before throwing any money at it for expensive engine, Id hand it to someone who knows nitro rigs really well. Either it be someone at your LHS if you have one close by or maybe a friend that can help you out.

 

[dubbiesRcs]

If you have a hole in the engine, then you need to address that. Either by replacing whatever broke if parts are available or buy a new engine.



But before I went to that expense, Id make sure to narrow down the problem. No reason to spend money on a replacement engine, if its just a cracked fuel line. That's a couple bucks vs. a couple hundred. If its an actual engine problem that severe, it probably shouldn't start in the first place and even if it did, it will run like crap.



But start at square 1. And BTW, these are just suggestions from some stranger on the interwebz...so if you break it or cause harm to yourself or your RC, don't yell at me, I don't want to hear about it :



Clean it up.



Go over the fuel lines, every mm of it.



Check each fitting for cracks or broken.



Make sure the exhaust fittings are tight and that the rubber coupler is sound. Any crack here will leak. Also make sure that it is in the proper position and that its not just barely catching hold of either the manifold or pipe. And BTW, manifold can develop hairline cracks to that are hard to see until it eventually breaks completely off.



Check the entire fuel tank. Remove it if you have to, so you can inspect the mounts. These can get cracked. Make sure the fuel door is closing and sealing properly. Most have some form of adjustment to tighten if needed. Make sure all O-rings are okay and not showing damage.



If all look okay, then before I removed the engine, Id fill the tank and prime it so that the fuel lines are full of fuel. Let it just sit with paper towel or shop rag under it and keep an eye on it to see if there is any wet spots forming.



After an hour or so, Id fire it up. Is it running okay? Just let it sit at idle and watch it for leaks. Only this time make sure not to have paper towel or rags near the exhaust or engine, so they don't ignite by accident. What are the engine temps just sitting? Do you have a infrared temp gauge? If not you need one ASAP. If its running rich it will be running cold. This will cause excess fuel into the exhaust. without a temp gauge, your only guessing at this point, and most likely guessing wrong. But if it is running proper and still no leaks, then go run it in the yard for a while and keep checking it. If still nothing, then Id shut it off and let it cool down. Normally you should be removing any left over fuel out of the tank when your done running it, but for now let it sit and see if any leaks start while it cools. Keep checking for up to an hour. If nothing then drain the tank and lines.



Remove the engine and inspect all bearings, gaskets. Make sure the head is tight, but dont over tighten and strip the screws. Your most likely going to need to be able to remove the flywheel and starter assembly to inspect the bearings. Is this something you r able to do?



again, lots of 'maybe this' or 'could be that' going on. Could be its just one of the pitfalls of owning a nitro RC. They can be messy. I had 2 of the original TMaxx's when they first came out back @2000/01-ish and they both leaked like a sieve all over the chassis. In both cases it was just left over exhaust blowing out the muffler.



If you get to the point where you can't figure it out, or tearing into it is beyond your skills or comfort level, then before throwing any money at it for expensive engine, Id hand it to someone who knows nitro rigs really well. Either it be someone at your LHS if you have one close by or maybe a friend that can help you out.

Kk it took a while to read this but thanks

 

[wwit]

Kk it took a while to read this but thanks

Your welcome.

I was feeling generous with my time when I typed that. I was pouring rain in buckets here yesterday. Had it been nice , I would have been out enjoying my new nitro truggy instead of clacking away.

But wanted to try and cover the basics for your problem and be as clear as possible. You seam new to this. But figured this way it might help you find a solution faster than asking uneducated questions with only tidbit's of info being a picture and asking 'please help'. Doing it that way could take weeks/months to help you with. And I probably missed something as that was just what came off the top of my head.

Good luck with it.