sb13

My Feedback: (52)

Here's an odd situation. My 3.3 died last night. The glow plug was replaced today and it started no problem. After 3/4 of a tank ran it died after I turned it over on it's lid. Usually does'nt but oh well it did. I could not start it again after that. Temps were 212 when it died so not running hot. My easy start starter only had one light lit, the glow plug light was not lit. Although I just put the new plug in it 3/4 of a tank of fuel ago I went ahead and through another new one in it and it fired right up. Ran it for a couple of minutes, temp was at 208 when it died again. Every plug that comes out looks good, nice color and the wire is not destorted. Tuning is good, HSN is set almost 1/4 turn back rich after to the point the motor would bog, LSN pinch test is perfect with a perfect idle. I don't get this, lets here everyones opinion here please. It's cooling off now and I'll see if it starts right up once it's cold. The motor has just over 1 gallon through it after break in. Break in was done with care and by the manual.

sb13

My Feedback: (52)

Motor cooled off and still would not start. Put in another new plug and it fired right up. The plug I took out this time looked fine again.

sb13

My Feedback: (52)

I have a rcats glow ignitor that I use with my other nitro engines. It gives you an LED power level (amps) read out. I put it on both plugs that died today and read no power. I put it on the savages gloe plug and get a power reading. So, I have 3 Traxxas plugs that all came from my LHS that are dead after no use what so ever. You guys think they received a batch of defects? I ordered McCoys but hate to wait for them to get here to check it out.

jaketrouble

i think i read a post about this before not long ago.. flip back through 10 pages or so and see if you can find it. i think it had something to do with running way too rich burning up the plugs.. i could be wrong but i do remember seeing a post about this..

Mspeed

A couple things comes to mind, One is you might be too lean. I know it sounds like your not according to your reading on temps and your HSN adjustment, but you still might be. If your power is still good were your HSN is set right now, then go richer and see if that helps. Also, check your head bolts to make sure they are tight and look for leaks all over the complete system.

The other thing that I thought of is the plug your using vs nitro%. Are you running 30% nitro or 33% on a Mc-59 mcoy? That can blow plugs fast. You need a colder plug on higher nitro percents.

matts6887

i think mspeed could very well be right on this one. U could be running it a touch too lean, even though it might not seem like it due to the temp reading u are getting. But on the other hand, it is quite possible that there could have been a very small "bad batch" of glow plugs out there. Now, I personally have never seen 3 at one time go bad like that, but I have seen 1 be bad right out of the package brand new...

iamnot

too rich will kill glow plugs as easily as too lean
temps of 208 & 212 are too cold for that engine
so i'd tend to think you're too rich

sb13

My Feedback: (52)

I agree with what you guys are saying. The motor has always ran on the cool side. If I lean it out much more it will bog. I do not have a hole cut in the windshield for cooling either. I run 20% nitro. I'll have to check for leaks I guess.

beer=food

If you lean it out more it shouldnt bog down, it should tune in better or if you go to far and its set to lean it will cut out. If its bogging down its to rich, and thats the likely cause of fried glow plugs, iamnot right again !

sb13

My Feedback: (52)

I used the wrong word I guess, I know better too. You guys can't help without a correct describtion so sorry. It does'nt bog, it does cut out. I did get a full tank ran through it on an OS plug tonight but my tuning seemed to be bad, very bad. I played with it but in the end the glow plug has a bronze color to it, a dark color. That would be rich I assume? I can't lean it out much though becouse it will cut out. I've never had a traxxas motor run this cool this lean but yet the plug is a little dark. I lean it out right,?? with that color plug. What do you do when you can't? This is a strange deal to me.

matts6887

A dark color I think if i remember correctly does in fact mean it is too lean(someone else correct me if i am wrong)

iamnot

cut and pasted from the ron paris tuning guide

OS and Turbo glow plugs go gray sooner [easier] than McCoy plugs; this is not necessarily bad. Actually when A new plug wire just goes slightly gray after a 5 or 10 minute hard run it means your very close to an optimal horsepower tune, but be careful the next step is TOO LEAN!
My rule of thumb.
1} Wire and surrounding bottom of plug wet, with like new shiny wire = rich side of optimum power 85%
2} Wire and surrounding bottom of plug starting to dry and wire starting to gray = Very close to optimum power 95%
3} Wire and surrounding bottom of plug dry, wire totally gray but not distorted optimum power 100%
4} Wire and surrounding bottom of plug dry, wire distorted = slightly lean DANGER!
5} Wire and surrounding bottom of plug dry, wire broken and distorted or burnt up = extremely lean possible engine damage!
Note: You can only “Read” your plug in a nearly new state [Wire like new and shiny] A gray plug can still operate well. After it has totally gone gray, performance can start to fall off. To test just put in a new plug and if there is no difference in performance save the gray one or put it back in.

based on your description of your plug and mr. paris' guide
i still think that you're rich

sb13

My Feedback: (52)

If it is rich I can turn the HSN about 1 hour max before it will cut out. The LSN revs for about 2.5 - 3 seconds then dies when doing the pinch test so I might be able to richen it up a little and then go back to the HSN and see what happens. I know the high side is usually done first though.