Flywheel Question

[Cretosx]

When i turn my engine's flywheel there are two parts of compression? what is the issue behind this i assume it's something to do with my piston and sleeve?

 

[cbaker65]

When i turn my engine's flywheel there are two parts of compression? what is the issue behind this i assume it's something to do with my piston and sleeve?

Not sure how to answer the ? How old is the engine?
It could just be the way the piston is going up into the pinch of the sleeve.
Is the engine hard to start?
Also,when you quit running the engine,run the piston down out of the
top of the cylinder,it will save the pinch of the sleeve an prolong the life
of the engine.Do this before the engine cools off from running.

 

[Cretosx]

Engine is about a year old, the engine is extremely easy to start when throttle is applied, just wondered because none of my other engines flywheels do this, even though i have an exact same engine that's actually older it still doesn't happen just wondered really.


Thanks for the tip.

 

[cbaker65]

Engine is about a year old, the engine is extremely easy to start when throttle is applied, just wondered because none of my other engines flywheels do this, even though i have an exact same engine that's actually older it still doesn't happen just wondered really.


Thanks for the tip.

Oh,I have an engine or 2 that does that,but really never payed too much attention to it.
I dont no the sience behind it either,but I do know that the piston rod gets hammered,the
rod bushing get distorted & worn out,so people tend to change that out after some engine
break-in,an some run time on it,nobody wants to frag a $ 400.00 racing engine.
Hang around,someone may know the true answer...

 

[Cretosx]

Oh,I have an engine or 2 that does that,but really never payed too much attention to it.
I dont no the sience behind it either,but I do know that the piston rod gets hammered,the
rod bushing get distorted & worn out,so people tend to change that out after some engine
break-in,an some run time on it,nobody wants to frag a $ 400.00 racing engine.
Hang around,someone may know the true answer...

Found out what causes it, the conrod / crackpin are worn once replaced it stopped doing it.

 

[Rolex]

When i turn my engine's flywheel there are two parts of compression? what is the issue behind this i assume it's something to do with my piston and sleeve?

On the way up you're feeling the compression as the piston reaches the top. Then it hits its peak and since you're raising the piston slowly, the compression has time to bleed off. After turning past top dead center you're actually feeling a vacuum as you turn the flywheel and bring the piston down since the compression is gone and the piston has no incoming air.
At normal RUNNING RPM the compression will not bleed off on the way up and after ignition there will not be a vacuum on the way down.

 

[ninnon]

What Rolex said.