How should engine bearings feel?
#16

As wingracer stated. You have to care for motor, no matter what. The fuel is Hygroscopic so it will attract water / rust.
Also many of us actually fully disassemble our top of the line motors to inspect and further clean them before break in. This way we know the true condition of the motor prior to use, and should anything happen.
Also many of us actually fully disassemble our top of the line motors to inspect and further clean them before break in. This way we know the true condition of the motor prior to use, and should anything happen.
#17
#18
Tech Adept
#19

As wingracer stated. You have to care for motor, no matter what. The fuel is Hygroscopic so it will attract water / rust.
Also many of us actually fully disassemble our top of the line motors to inspect and further clean them before break in. This way we know the true condition of the motor prior to use, and should anything happen.
Also many of us actually fully disassemble our top of the line motors to inspect and further clean them before break in. This way we know the true condition of the motor prior to use, and should anything happen.
Now i am far more confident in my abilities and have cleaned this engine out and removed the rust from the crank. Its actually a very rewarding and satisfying process!
In future I will dissasemble and inspect my motors before running them. I will also be extra careful taking my time in the after run process.
#20

I think i can draw a conclusion to this thread now for any future viewers to see.
I purchased this engine with a leaky front bearing from the factory and did not bother to look any further into it.
I proceeded to break in the engine with the leaky front bearing and this caused a less than ideal fuel mixture for break in (too lean).
At this point aside from the leak from the front bearing, nothing appeared to be wrong. The engine ran fine without any bearing noise.
After about 10 practice sessions at the track, i noticed the engine would not hold a tune or idle correctly. I would tune the high idle out, go out for one lap and then it would be all over the place again. The engine also made a strange metallic bearing noise at this point and the front bearing was leaking more than previously.
Upon inspection, the front bearing seal was leaking air and oil so needed to be replaced. The rear bearing was not smooth and felt slightly grindy as well as having some rust on the outer race.
The crankshaft was also rusty.
This means the rust on the crank and rear bearing outer race most likely caused the rear bearing damage in conjunction with a slightly lean fuel mixture caused by the front bearing seal failure, causing the rear bearing to emit a metallic bearing sound during running.
The lean fuel mixture during break in has probably also reduced the engine's overall lifespan.
The solution is new front and rear bearings combind with a strict after run maintenance regime, buring off all fuel in the engine for storage and removing all fuel from the tank and lines. After run oil should also be applied throughout the engine. It is also a good idea to inspect the internals of new engines before running them.
Thanks for the replies everyone
I purchased this engine with a leaky front bearing from the factory and did not bother to look any further into it.
I proceeded to break in the engine with the leaky front bearing and this caused a less than ideal fuel mixture for break in (too lean).
At this point aside from the leak from the front bearing, nothing appeared to be wrong. The engine ran fine without any bearing noise.
After about 10 practice sessions at the track, i noticed the engine would not hold a tune or idle correctly. I would tune the high idle out, go out for one lap and then it would be all over the place again. The engine also made a strange metallic bearing noise at this point and the front bearing was leaking more than previously.
Upon inspection, the front bearing seal was leaking air and oil so needed to be replaced. The rear bearing was not smooth and felt slightly grindy as well as having some rust on the outer race.
The crankshaft was also rusty.
This means the rust on the crank and rear bearing outer race most likely caused the rear bearing damage in conjunction with a slightly lean fuel mixture caused by the front bearing seal failure, causing the rear bearing to emit a metallic bearing sound during running.
The lean fuel mixture during break in has probably also reduced the engine's overall lifespan.
The solution is new front and rear bearings combind with a strict after run maintenance regime, buring off all fuel in the engine for storage and removing all fuel from the tank and lines. After run oil should also be applied throughout the engine. It is also a good idea to inspect the internals of new engines before running them.
Thanks for the replies everyone
#21

The only thing in the whole universe that can save your engine from rusting is you.
To trust in some drops of ARO or the nasty promises of the fuel manufacturer is just playing russian roulette.
#22

Hello Max Rackstraw,
If You have the time, You should take out the engine of the chassis. Take out the Air Filter and Manifold/Pipe, and close all the holes including the Fuel Nipple. Clean the exterior of the engine thoroughly. Then take out the Back Plate and put tissue/napkin on the lower side of the crankcase while tilting back the engine to absorb any fuel left on the crankcase. Then put some drops of After Run Oil and put back the Back Plate. You could store it inside a Zip Lock bag to further protect it.
A while ago I like to use TAMIYA Engine Treatment spray, it is the best product to avoid rust!!! But sadly it is not available anymore. I've been trying to spray WD-40 seems to be OK so far.
Cheers..
If You have the time, You should take out the engine of the chassis. Take out the Air Filter and Manifold/Pipe, and close all the holes including the Fuel Nipple. Clean the exterior of the engine thoroughly. Then take out the Back Plate and put tissue/napkin on the lower side of the crankcase while tilting back the engine to absorb any fuel left on the crankcase. Then put some drops of After Run Oil and put back the Back Plate. You could store it inside a Zip Lock bag to further protect it.
A while ago I like to use TAMIYA Engine Treatment spray, it is the best product to avoid rust!!! But sadly it is not available anymore. I've been trying to spray WD-40 seems to be OK so far.
Cheers..

#23

The reason for changing fuel is more because the fuel i have now is quite old and used to sit in a non water tight garage.
#24

Hello Max Rackstraw,
If You have the time, You should take out the engine of the chassis. Take out the Air Filter and Manifold/Pipe, and close all the holes including the Fuel Nipple. Clean the exterior of the engine thoroughly. Then take out the Back Plate and put tissue/napkin on the lower side of the crankcase while tilting back the engine to absorb any fuel left on the crankcase. Then put some drops of After Run Oil and put back the Back Plate. You could store it inside a Zip Lock bag to further protect it.
A while ago I like to use TAMIYA Engine Treatment spray, it is the best product to avoid rust!!! But sadly it is not available anymore. I've been trying to spray WD-40 seems to be OK so far.
Cheers..
If You have the time, You should take out the engine of the chassis. Take out the Air Filter and Manifold/Pipe, and close all the holes including the Fuel Nipple. Clean the exterior of the engine thoroughly. Then take out the Back Plate and put tissue/napkin on the lower side of the crankcase while tilting back the engine to absorb any fuel left on the crankcase. Then put some drops of After Run Oil and put back the Back Plate. You could store it inside a Zip Lock bag to further protect it.
A while ago I like to use TAMIYA Engine Treatment spray, it is the best product to avoid rust!!! But sadly it is not available anymore. I've been trying to spray WD-40 seems to be OK so far.
Cheers..

#25

We've answered the question of are my bearings bad (probably)... And why they went bad... But does anybody have an answer to the title of this thread? Its not as important now since i dont need to feel the bearings or even look at them... I know they're bad. But for future reference, can anybody describe how engine bearings should and shouldn't feel?
#26
Tech Master
iTrader: (9)

We've answered the question of are my bearings bad (probably)... And why they went bad... But does anybody have an answer to the title of this thread? Its not as important now since i dont need to feel the bearings or even look at them... I know they're bad. But for future reference, can anybody describe how engine bearings should and shouldn't feel?