hello,
I'm in the process of rebuild my engine because of the engine block is crack a few years ago, and I don't know what caused it because I buy the car second hand. May be waterhammer?
I have try to rebuilt the engine with new hournal, new piston and seal engine block a after I got the car, but I got bad engine tremor when idle.
I assume if my crankshaft is bent? or my crank shaft not balance?
Now I want to rebuilt again my engine with new engine block to replace mine that is crack and have deformation.
my question:
which cause my engine idle tremor but after 700 up rpm it will be smooth?
can crankshaft bent?
or I should balance my crankshaft and my flywheel?
Need advice and help
thank you in advance
markus
bent crankshaft?
Moderator: martauto
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markus_74
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HJG-E30
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Combustion is likely to be unstable / incomplete below 700 RPM. Are you sure the idle speed is correct? This could be contributing to the "tremor".
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markus_74
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hello HJG-E30
idle speed without air conditioning it is about 600-700 rpm and with air con it will be increased to 800.
how to make a correction? as idle speed is controlled by ecu?
and what do you mean incomplete below 700 rpm?
thank you
idle speed without air conditioning it is about 600-700 rpm and with air con it will be increased to 800.
how to make a correction? as idle speed is controlled by ecu?
and what do you mean incomplete below 700 rpm?
thank you
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HJG-E30
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Vibration forces from an out of balance engine would tend to increase significantly with increased engine speed.
This would be far more pronounced in a four cylinder engine. A six cylinder should not exhibit any vibration from engine imbalances whatsoever.
Your tremor is more likely to be an idle speed that is too low, resonating the mounts and amplifying the vibration.
If engine speed is too low, combustion quality will be poor.
I'm not sure how idle speed is corrected.... you haven't stated what engine you're using.
Of course, your engine mounts may need replacing!
This would be far more pronounced in a four cylinder engine. A six cylinder should not exhibit any vibration from engine imbalances whatsoever.
Your tremor is more likely to be an idle speed that is too low, resonating the mounts and amplifying the vibration.
If engine speed is too low, combustion quality will be poor.
I'm not sure how idle speed is corrected.... you haven't stated what engine you're using.
Of course, your engine mounts may need replacing!
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markus_74
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ok, mine is m40 b18 engine
my engine mount is in good condition but it is not original bmw, it is oem after market, does the rubber quality is different?
But I know the engine is wrong not the mount.
so it is not my crankshaft not balance and my crankshaft not bent?
sometimes if I drive I'm hear an explosion from my back of my car in the muffler but rarely.
my engine mount is in good condition but it is not original bmw, it is oem after market, does the rubber quality is different?
But I know the engine is wrong not the mount.
so it is not my crankshaft not balance and my crankshaft not bent?
sometimes if I drive I'm hear an explosion from my back of my car in the muffler but rarely.