turbohardtop

I was wondering how would someone know ifthe engine is fully broken in? I ran about 10 tanks in my Axial .28rr and it is not fully dialed in yet. It has good power but I am sure I can get a little more power by leaning it out more. However, I am a little hesitant to do so since i do not know if the engine is fully broken in and do not know if the engine is ready for more. Is there an indication that the engine fully broken in? It still has a really tight pinch on it. thanks.

SManMTB

Temps will drop and you will be able to run longer on a tank. There should not be much metal to metal pinch and you should be able to turn it over by hand (with a flywheel attached) but there should be a noticeable 'plop' when you turn it over.

kraffty

My Feedback: (2)

After you get it broken in it will be worn out so be careful. I have 2 engines that as soon as i leaned them out where they pulled good power they lost compression and are crap.The engine manufacters should be paying attention because all i see in these forums are how all these engines are worn and hard to start etc.

SAVAGEJIM

Continue to run your RR until you hit about a half gallon to a full gallon of fuel. Run it with care, with some WOT, but nothing severe.

The primary clue to your engine being fully broken in is when you do a full trigger pass on a top speed run, is that you engine does not blubber at the higher RPM bandwidth (sounding like "Wub! wub! wub!"). If it blubbers like this, back of the trigger, and keep the engine on the rich side (but nit too rich though) and coninue to drive moderately. Once the blubbering does not occur anymore AND you engine is tuned for perfromance (not TOO lean though!), then your engine is fully broken in and you can WOT it for more perfromance driving.

rcnitrohead

Kraffty, from what you typed, you have displayed how inexperienced you are... When engines are fully broken in, they run reliable, they have a stable idle and have long run times. An engine doesnt lose compression when its broken in Especially in an Axial RR, you need to run 3/4 a gallon before you lean out..[8D]

SAVAGEJIM

Actually, the RR HSN is extremely rich from the factor, and I had to turn mine in by about 3quarters in lean to get it to run to operating temps during break-in. On my second RR, I think i turned it in by a half turn for it to run correctly for break-in.

Now, the LSN on the other hand is NOT rich enough! I had to turn the LSNs on both my RRs about 2/5 turns out rich!

When breaking in an engine, DO NOT be afraid to lean it! It is very important that these engines reach opeating temps ESPECIALLY during break-in! Of course, keep it on the rich side, but lean enough to run for a proper heat cycling.

SManMTB

Please post your incorrect info in another forum.

j_blaze

I use the sprinkle method. When I break in the engines I do it on the box with a fan on it and a piece of newspaper under the exhaust. In between tanks I change out the newspaper. Usually there is a fine silver dust in the exhaust puddle, sprinkles. When I remove the newspaper and there are no more sprinkles, tada, break-in over, time to tune. Its worked for me the last two engines, I think I heard of someone else doing it that way too. Another way would be to do the manufacturers recommended number of tanks then let it idle on newspaper for a minute and check then.

j_blaze

What temp do you shoot for? I like to keep it between 210 and 220 just in case the temp gun is a bit off or can't reach to get an accurate temp.

rcnitrohead

Jim, I meant not to lean for performance Some engines do come exessively rich from the factory

SAVAGEJIM

That is a good temp. But if you know your engine is going to spend most of its time at 250degrees, by all means, break-in the engine at 250 degrees. For the 1st, 2nd, and even 3rd heat cycles, you might not even reach 250degrees F, just get it to 200+ degrees F then lean a little more as the engine loosens up.

SAVAGEJIM

Sorry, I should have know you already known that; afterall, you have contributed alot to the break-in discussions [8D]

rcnitrohead

[8D][sm=49_49.gif] As have you[sm=thumbup.gif]

Shannonadams

Typically, an engine is considered fully broken in when it has undergone a sufficient running period to allow its internal components to settle and adapt to each other. Common indicators include smoother performance, easier tuning, and a reduction in the tightness of the piston pinch. However, the exact break-in process can vary depending on the engine type and manufacturer's recommendations.

In the case of your Axial .28rr, although it may have good power after running 10 tanks, the tight pinch suggests it might still be in the breaking-in phase. It's advisable to consult the engine's manual or contact the manufacturer for specific break-in guidelines to ensure optimal performance and longevity.

BarracudaHockey

My Feedback: (11)

2007 thread, I think they figured it out by now

1QwkSport2.5r

Despite the necrobumping, the mechanical pinch is NOT an indicator of how broken-in an engine is. Discerning operators know that the longer an engine maintains mechanical pinch knows the engine is in proper mechanical condition. When the cold mechanical pinch is gone, the engine is already at its peak or on the downhill side of condition and is losing power. Anyone that is lapping a piston or milling the piston for less mechanical pinch is actually taking gallons of life out of an engine (artificially wearing it out). Preheating an engine prior to starting it will literally add gallons of life to an engine.