My 93 corolla wagon needs a new water pump after 140K miles. So I bought the part from shucks and started tearing into the timing belt area of the engine because the water pump housing bolts onto the side of the engine block behind the timing belt and below the engine mount bracket. To make a long request short, I am having problems getting the timing belt off.

Question: do I need to remove the Main drive pully off the engine output shaft off to loosen or slackin the drive belt? If I do, how is this accomplished? I cannot hold the pully with sufficient force (stop if from turning) to break the center pulley bolt free. Is there a special tool I need or is there a trick I am missing. Its a 17mm bolt holding the pulley on to the output shaft.

On most cars there is a tensioner that is actually putting the tension on the timing belt. Usually this is much easier to loosen than pulling the crankpulley off to reduce the tension, although that is an option sometimes.

Make sure everything is turned to TDC before attempting to remove the timing belt, I don't have my Corolla book anymore and can't remember where the tensioner is to reduce the slack, but you may consider purchasing/borrowing a maintenance book.

BTW If you need to remove the crankpulley still (for another reason) you can generally two one of two things:

1. Use an air tool
2. If the crankpulley has other bolts on it, have someone put tension in the other direction on those bolts while you attempt to break free the 17mm bolt. This can be a royal pain though.

My 93 corolla wagon needs a new water pump after 140K miles. So I bought the part from shucks and started tearing into the timing belt area of the engine because the water pump housing bolts onto the side of the engine block behind the timing belt and below the engine mount bracket. To make a long request short, I am having problems getting the timing belt off.

Question: do I need to remove the Main drive pully off the engine output shaft off to loosen or slackin the drive belt? If I do, how is this accomplished? I cannot hold the pully with sufficient force (stop if from turning) to break the center pulley bolt free. Is there a special tool I need or is there a trick I am missing. Its a 17mm bolt holding the pulley on to the output shaft.
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Thanks Paul and FYI: Toyota Mfg Corp. has two special tools that assist the mechanic with the tear down. The first is a Main Pulley bolt remover that has 2 teeth the straddle the main bolt socket. It is used to break free the centering bolt holding the main pulley on the engine output shaft. The second is a leverage wrench with a pin that is inserted into a hole just below the drive belt tensioner pulley. It allows you to easily compress the tensioner and slacken the belt. The boys at toyota dealership were kind enough to share there fine tools with me however the real lesson learned from this experience: If you have to replace a water pump on a 1.8L Corrolla engine: have a shop do it that owns the special tools. Rental cost me $30 this weekend, the pump was $50 and my time was ~7 hrs. This more then covers the $200 the local shop wanted to do the job.