In an 1991 olds 98 do you have to remove the engine and engine mount to get the bottom bolt in when installing a new water pump?
Noyou don't. I just changed my water pump in a 91 olds 98 3.8 liter. This is the way I did it. Put car on ramps or jacks stands. There is two bolts under the motor mount that you need to loosen but not take out. Then jack the engine up to the bar that goes across. Then take out the bolts that hold the motor mount on the top. Once you hav e done this then remove the belt. There are three bolts that hold the bracket, Take them off. Oh, i forgot there is a bolt that goes through the motor mount take it ot before you take the bolts out on top that hold the motor mount. Once you get the bracket off then the water pump is exposed for your taking. You will have to put the belt back on to loosen the bolts that hold the pully. that is pretty much it. Make sure you use something to lube the bolts because mine were rusted and din't want to losen especially the bottom to bolts that hold the motor mount. once I got the bracket off it only took 15 min. to take off clean and put other one back on. It is not hard but it saved me $150 to do it myself. Part was only &25 lifetime warranty. have fun. if you need further help you can send me an email at email@example.com