I need a new water pump for my 87 GL, EA82 Carb. However, I don't know which one. Autozone has two snout lengths. Here is the link.

there's a couple threads here detailing how to know which you need, i recall milesfox laying it out nicely. search button will nail it for you.

found one. For others' reference, here is the quote. Also, the search button here sucks.

 

...The 'long one has a 110mm shaft, the short one is 105(for turbos)

 

the difference is, the 110mm water pump has studs on the water pump itself, and the pulley slips over it.

 

the 105 mm had holes on the shaft, and the pulley bolts onto it, and the studs for the fan are contained on the pulley itself.

 

other than that, the WP housings are the same. some may be new, some may be rebuilt.

 

some will have a stamped steel impeller, some will have a vane type cast impeller. the cast units should be better quality. the less quality ones are like alternator fins.

 

you should expect to pay about 40 bucks for a water pump