The MGA With An Attitude
Photos and notes compliments of Tom Pollak in Binghamton, NY, USA

I decided to install an early MGB harmonic damper crankshaft pulley to my MGA 1600. I could not find the answer to the question as to whether there was enough clearance between the steering rack and the front of the engine to swap-out the original pulley and install the (thicker, though same diameter) MGB pulley. As it turned-out, the installation can be done without raising the engine. It is tight but there is about a 1/16th" clearance to allow the new pulley to align with and slip over the end of the crankshaft.

Here are some things found during this installation:
  • Remove the radiator, loosen the generator, remove the fan belt, fan blade and fan pulley.
  • Remove the crank pulley nut using a 1 5/16ths" box-end wrench. (A socket will not fit and an open-end wrench will guarantee only damaged hands and not necessarily a loosened crank nut!)
  • The end of this crankshaft was "mushroomed" about 0.0015" so it was necessary to remove the woodruff key and use a fine honing stone to carefully smooth-off the slight ridge.
  • To make the installation, it was necessary to ream-out the pulley I.D. about 0.001" to 0.0015". It doesn't sound like much but it made a BIG difference! This was accomplished by wrapping a strip of 120 grit, cloth-backed sanding material around a socket that was close to the size of the pulley I.D. and cautiously rotating the pulley around the socket and abrasive material.
  • Marking the position of the center of the pulley keyway slot with a fine tip felt pen helped greatly in aligning the keyway with the woodruff key.
  • The felt seal was replaced and the MGA timing cover was reused. (Be sure to reinstall the oil thrower correctly if it is removed from the crank.)

  • The new damper has two timing marks to accommodate either the timing cover for the MGA (or early MGB) with "lower pointers" or the cover for the later MGB with "upper pointers". The pulley timing mark was verified as correct with the MGA timing pointer and with TDC of #1 piston.

    Tom Pollak

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