Engine Blues ...
 

:(

I'm having issues with my nitro engine. When I first purchased the engine I broke it in to the tune of 25+ tanks with the help of a heat source to bring the engine up to 200 degrees anything lower and it just would cold seize. I'm about 45+ tanks into it now and I've been running the car medium to top speed (as i assume the engine is broken in) Anyhow, the only way I've been able to start the engine is with the glow plug slightly unscrewed on the starter box. Now, going back to about 2 weeks ago I was able to do this without any problems. Well I thought so, I tried it again the other day and for some reason the engine is just seizing at TDC at the pinch point as to where I burned up my brandnew starter box engine trying to turn it over. The question is what am I doing wrong?

Question 1: What engine and fuel are you using?
Question 2: 200 what? Celsius or Fahrenheit? I hope its Fahrenheit!

That sounds like one hell of an engine!

Doesn't sound like you are doing anything wrong, but possibly letting it run only when its around 200 is not letting the piston and sleeve wear themselves in together like it would when its colder because of expansion?

JP FX R03 .21

...and the rest? :D

There were several configurations with the R03 but the one with the Microcasted piston was known to have a very tight piston, the same as the first 35-plus-21 models. It can take up to 5 liters of use before the piston becomes realy loose, until that time you have to warm up the engine slow and carefully at avery cold start but also with a warm start it is wise to take the 1st lap easy.

It is wise to replace the rod very quick because that one had to take a lot of stress.

Regarding the comming back tightness of the piston is something natural. Every tim you heat up the engine more than before (builded up performance) there will be a little bit of grow in the piston when cooling down.

JP FX R03 .21 Standard ... it was preheated to 200-220 Fahrenheit with a heat source @DJ

Hmmm, micro-casted eh! I don't ever remember my Serpent Nova Mega .21 7P EV05-MS being this difficult and I believe it was also micro-casted. Ohh, geez how I miss that motor I should of just brought one of those instead ... Anyhow I think at first I was going to suspect a defect in the R03 casting, but ok I'll take it easy and keep going with the babying process it's a pain tho..

(One other interesting thing considering the amount of tightness there aren't any noticeable scratches on the piston or sleeve)

Now my last question is should I replace the connecting rod now or wait? I think it's a R7 lightweight rod ...

the piston and sleeve should have no major scratches or noticeable marks, otherwise that would be showing that that area is seeing alot more friction than the rest.

If it's gone through a fair amount of fuel like you say it has, it would definitely be a good idea to replace the rod and the pin in the piston to be safe and not end up with a stretched rod, rendering basically the entire engine as useless as the "k" in "knife" :D
Good luck with your engine, sounds like you got a keeper for a few years!

Indeed with a tight piston some scratches can be noticed, expecially on the exhaust side. When you are already beyond 3 liters of use (25 tanks) then it is time to adjust the engine to maximum performance, only then you will speed up the proces but as mentioned before you have to take some laps to build up the performance without stalling the engine on the tight pinch.

Other option is "handlapping", ther are some topics aubout this and some people who can do this. In a way they polish/grind the piston a tiny bit smaller.

Part II.

Okay, I just don't understand what I am doing wrong. I don't think my relationship with my engine is going to end on a sweet note. I recently have been having problems starting my engine now. It won't turn over at all under it's own power (meaning it only runs with the starter box assisting it)

I recently changed out my turbo Novarossi plug for a fresh RB plug and it just won't turn over with the new plug. I want to know did I create a problem by switching out the existing plug considering the RB is incompatible. It would appear as if the engine is flooding every turn on the box. I'm on the verge of burning up another starter box engine please someone shed some light this is insane ... I'm going on a theory of a egg shell sleeve syndrome?

btw... I'm running Byrons 30% 9% Oil and previously ran this without any problems. I will say prior to this I ran 20% Byron and O'Donnell and never had problems...

If you had eggshape syndrome, Im pretty sure you would notice it, but it isn't impossible.
Turn it over by hand with the pipe off. Listen to hear how much air escapes once the piston closes the exhaust port, if you can hear very little to nothing at all, it should be all good.
If you can hear a fair amount, and you are able to continue pushing the piston up, then there is a compression leak.
Changing from a Nova to an RB is nothing - they are basically the same, only (from what I've been told) and RB 7 is like a Nova 6.
If it does sound rich and loading up on you, just lean it up a little until it at least starts running under it's own power.

Update:

Out of fustration I decided to give it a go after I typed the above message. Okay, for starts I changed back to the original Nova 6 Plug that came with the engine (strangely it looks wider than the RB 6 plug)?. I then proceeded to heat the engine up with my heat gun to about (200-210F) and the engine started up no problem. I ran 3 tanks continuous and then let it cool. This is so weird... :confused: considering yesterday evening it was no chance in heck it would turn over cold...

I'm going to throw out the egg shell syndrome you are correct no chance impossible I don't hear anything... Now the only other issue I have is that I have to slightly unscrew the turbo plug to lessen the compression to turn it over on the box still seems dirt may get in somehow ...

I sadly don't remember having this much trouble with my Nova EVO5 MS back in "01

If the RB plug didnt work, did you check if it still lit up in your hands?
Good to hear you got it started :D

It's one of those love hate situations, like a stubborn girlfriend no wonder I'm single. I just can't figure it out sometimes. The RB plug lights up :confused: ... I like to think I have full control of my hobby engines, but the latter with women sheesh ... :( ok well next week I will take it out on the field and see what happens ...

heheh, story of my life too :D
If Novarossi works for you, then stick with them, RB should basically be the same as Novarossi - the bodies are almost identical apart from some slight variations :s

whats the actuall run in process you are using?

most isswues relove around the miss conception of the user just running fuel through there motor realy rich y6ou need to break that sucker in buy running around a track at high temp if ou live in a cold climate its a bit harder

I did a combination of the WOT method and the sit and idle method ...