How many different types of Harmonic Balancers/Vibration Dampeners are fitted to M20B25? What are the physical differences between them? Are they interchangable? I am rebuilding an M20B25 engine an want to know what to look out for.
Cheers
M20B25 Harmonic Balancer/Vibration Dampener
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Templ8e30
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I take you're talking about the rubber damped pulley on the front of the crank ?
If so there's 2 types and they are not interchangeable, the later motronic type has teeth around the edge and the earlier jetronic type doesn't.
Cheers,
Iain T
If so there's 2 types and they are not interchangeable, the later motronic type has teeth around the edge and the earlier jetronic type doesn't.
Cheers,
Iain T

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reggid
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Yes, the one on the front of the crank.
Don't all the M20B25 use motronic? There is supposed to be different types for the M20B25's, even the eta's use a different harmonic balancer than the i's do. The later M20B20 use the same as the later M20B25's though. I need to know what the differences are between the ones used on an M20B25 motor.
Thanks
Don't all the M20B25 use motronic? There is supposed to be different types for the M20B25's, even the eta's use a different harmonic balancer than the i's do. The later M20B20 use the same as the later M20B25's though. I need to know what the differences are between the ones used on an M20B25 motor.
Thanks
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bottlecapE30
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one has teeth on it and the other is smooth i think it differs based on the version of motronic you have 1.0 has smooth and 1.3 has teeth (i think). the etas have no teeth

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reggid
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So what i have so far is
- all M20B25 harmonic balancers with teeth are the same.
- The eta have no teeth (apart from the US super eta which has teeth but a different pulley size)
- all M20B25 harmonic balancers with teeth are the same.
- The eta have no teeth (apart from the US super eta which has teeth but a different pulley size)
