Northstar Engines and System Technical Discussion Discussion, Another N* Oil Pump question in Cadillac Engine Discussion; Seems the oil pump on my 97 STS just keeps throwing me curve balls. Hopefully this is the last question ...
Seems the oil pump on my 97 STS just keeps throwing me curve balls. Hopefully this is the last question I have on it. The very end of the crankshaft is machined a few thousandth's or so which creates a lip about 1 inch from the end. The crank pulley will not go past this lip when I slip it on the crankshaft by hand so the crank pulley ends up being about 1 inch from the oil pump drive sleeve which it is supposed to be torqued up against. So my question is - Is the crank pulley supposed to be installed with some type of press BEFORE it is torqued down or will torquing the crank pulley bolt down to 37lbs + the additional 120 degrees force it past the lip and up against the oil pump drive sleeve? I have attached a couple of pics below. The 1st pic is the pic of the end of the crankshaft showing the lip where the pulley stops when installed by hand. The 2nd pic shows the 1 inch or so gap between the pulley and the front of the oil pump/oil sleeve. Any help much appreciated.
Thanks for the reply. I found the following install tool. Do you know if this is the type of tool used to install the pulley? If so I should be able to buy the bolt, nut, bearing and washer and make my own install tool for a lot less then $75.
Do you know approximately how much force is needed to get the pulley seated to the oil pump sleeve?
I would think once its started onto the shaft and if its line up then it should go on with less force then what is the starting point before torquing to 120 degrees. If not then you may start torquing to 120 degrees before the pulley is fully seated to the oil pump sleeve and get a false torque setting.
Yes, you do not need the special tool. Just get a longer bolt with the same threads as the crank bolt and stack some greased washers against the pulley hub surface. It will take some force to press the pulley on. Once it is on, reinstall the crankshaft bolt and torque it to 37 ft lb and then an additional 120 degrees. Mark the bolt at one of the hub spokes and turn the bolt until the mark lines up in the same spot on the next hub spoke. This is a lot of torque and it is critical this torque is achieved because the crank pulley presses against the oil pump to turn it and generate oil pressure.