Hey guys. hope everyone is well. Ive been having some problems with my works B5 pro. It is in a losi 8ight 2.0 truggy coupled together with a 2013 pipe. I took my time breaking motor in and all that jazz and ran a gallon of fuel or maybe a little less after break in trouble free. I was loving this engine. Then one day the plug burnt up. I didn't have a spare Werks plug so I used a O.S plug that I had for a diff car which lasted about 3 tanks. So I then ordered 3 of the stock plugs (#5) and the engine runs good for about ten tanks then fouls another plug. my high speed is tuned to what I believe is good and low end is a little rich however it seems like my low end needle does not respond very well to tuning adjustments? Id like to state im not a newb with tuning but this engine really has me baffled. Does anyone have factory needle settings other than just flush with carb body? and has anyone had glow plug problems like this? Thanks a lot in advance guys!

I haven't experienced the troubles you are with glow plugs in my B5. Having said that, I find that my B5 is very sensitive to idle gap/LSN adjustment - two stage idle and/or does not like being a bit rich or a bit lean on the idle. (IMO less forgiving than other engines)

When I get the idle fuel and gap right (the key for me was correct idle gap) she'll reward me with a strong consistent idle. Get it wrong; she'll fuel up, go two stage, or i guess it could do a plug.

Double post

Re factory needle settings - flush, flush is the normal starting point.
Any other setting will depend on fuel, plug, pipe, altitude, ambient conditions etc, etc - so very hard to give a good indication.
I run the Werks Race Blend 30% (which normally tunes around 1/2 a turn or a little more leaner than other fuels) with a # 5 plug and the 2058 pipe.
Running at sea level with ambient temps at around 18 deg C and a little humidity, a "normal race tune" would see the HSN about 1 - 1.5 turns in from flush and the LSN around 1/2 - 1 turn in from flush (only approximate).
Whether that is of any use to you I don't know.

IMO - you would be better to start off at flush, flush on the needles with a pre set idle gap of .5mm and tune in from there as described a page or so back on the B6 thread.
This eliminates any guess work by going on other peoples settings - which will have a 95% chance of being quite different to what you require for your circumstances.

Just trying to track down your plug issues with a little more info:
What fuel / oil percentage are you running ?
Are the plugs damaged in any way, or have any kind of foreign material on them. Or are they just "oiled up" and no longer glowing properly ?

As mentioned, both idle gap and low speed needle settings are critical.
We have always found the low speed and idle gap only require very small adjustments - so in saying your low speed needle does not respond to tuning inputs, this would possible suggest either an incorrect idle gap setting and / or your needle balance is well out of kilter.

Is it 0.7 mm for idle gap or is it 0.5 mm?

Meet you in the middle at .6 mm :)

Seems the norm is between .5 to .7
It's pretty hard to get it exact, and I doubt .1 of a mm either way will matter that much, as long as you balance it with the low speed needle for the correct air/fuel ratio at idle.
Upwards of .7 is too wide though. I set as close as possible to .5

Some guys will set the gap below .5mm, but this can result in flame outs in longer races where you get into a bit of a groove and start driving a little smoother - resulting in engine temps dropping a bit as compared to when you were pushing at the start. When the engine temp drops the engine runs a little richer, and the idle gap becomes to small for the richer mixture. This is why you see a lot of guys starting to flame out around the 35 to 40 minute mark in hour finals.

hey thanks for your help guys. I understand that your tune will most likely not work for me. However I was un aware of the idle gap being so crucial and also so small. I did set it to about 1mm but maybe ill try smaller from now on. and plugs are nice and brownish in color. (def not lean) however my last plug to fowl the wire looked a little distorted right at the end almost like when you fowl a plug from being lean. I know the car is not lean and I cannot get it to idle smooth either. it loads up sitting for more than 5 seconds so im betting my idle was to high hence lsn not seeming to do much? I am running vp 25% with 9% oil if that matters anymore ha ha:)

also what do you use to measure your idle gap?

If you have them, drill bits.

I don't measure my gap - IMO it's too hard to measure a .1 difference; it's best to just listen to the engine and give it what it wants.

With the engine up to temp reduce the idle gap, then lean the LSN just until the revs come up and you get a stable idle.

If you like, repeat; reduce the idle gap a little further, then lean the LSN again until you have a stable idle.

At this point, conduct a pinch test to see where you are with the idle tune...

If you have a two stage idle at any stage, it means you are real close to an ideal idle tune - if/when you get a two stage idle, reduce the idle gap a touch more, and lean the LSN a small amount.

Eventually you will inspect the idle gap and think 'I can't believe that's right! The idle gap is tiny!' I know I did.

Once you have it right though, the idle tune will be very stable, you will rarely need to touch the LSN.

alright I will try this next time im out. What do you mean by a 2 stage idle?

http://youtu.be/kuO3g986JLI

Hear how it holds a high idle for a couple of seconds, then drops rpm = two stage idle.

There is no perfect idle Gap setting,
It will always vary pending your location and atmospheric conditions... the fuel you run and its oil content, Engine temp... the engines compression... Glow plug type etc etc

Generally in the 0.5 to 0.7 mark is where you will find the correct gap for a well tuned engine as the guys have stated



Dave

well guys things went from bad to worse.... I took truggy all apart today and gave her a good cleaning and going over.. decided to return needles to factory and set idle with engine out of car on the bench and while doing that change the glow plug as well. I took the plug out and the coiled wire inside the plug was half gone! I was thinking oh crap I wonder what that did to the engine so I pulled the head and button to find a button and piston that are all beat up from what I can tell looks like maybe the little glow plug wire getting beat around in there:cry: NOW WHAT? I don't know what to think of this. Ive been playing with these nitro cars for over 10 years and have never had a nice engine such as this werks and was so so so carefull breaking her in and have made sure it has never been lean. heck im hardly done break in I don't think this engine would even have a gallon yet!!!! what do you guys think?:mad:

Sorry to hear about the issue that you experienced. I've been doing this for a lot of years and I hate to say it but sometimes how long your engine lasts is just a crap shoot no matter what brand it is. However for a glow plug element to come apart your tune had to be off. Either the engine was simply too lean on the HS needle or the needle balance which I often talk about was off and you had a lean LS and a rich HS (which would show a normal temp) but in a nutshell excessive temperature is pretty much the only way that a glow plug element will melt and fall apart. Once the element falls into the engine and the motor is ran the element can bounce around and chew up the entire engine in minutes.

When the plug fails while driving you will normally feel a change in tune and your motor will start feeling rich. Any time that you notice your plug is dead I would advise that when replacing it always take a second to check the old plug to make sure that the element is intact. If you find that part of itis missing sometimes the element passes though the engine and just gets blown out the exhaust port without any damage. Sometimes it gets stuck in the exhaust port which will then cause the engine to seize, sometimes it gets bounced around in the combustion chamber damaging the head button and piston top. Either way though any time you pull the plug always take a second and inspect the element and if part of it is missing pull the engine apart and inspect/clean out the internals just to be safe.

Ouch - that's a bummer.