Changing a M715 Tornado oil pump

[kendelrio]

Ok all- going to be changing an oil pump when I get in. Looking at the TM it seems pretty cut and dry- remove the 3 retaining nuts, pull it out, replace the gasket and reseat the new one. Any heads up or words of wisdom?

 

[NDT]

Yes. This is a very tricky process as the oil pump drives the distributor. When you pull the pump out, it turns due to the helical gear. So basically it is impossible to re-stab the pump and have it re-engage the tab on the distributor. My suggestion: roll the engine to #1 cylinder top dead center. Remove the distributor cap. Note where the rotor is pointing. Pull the distributor. Pull the oil pump, carefully noting the clocking of the tab in the top gear AFTER removal. Take the new pump and clock the tab the same. Stab the pump. Stab the distributor and HOPEFULLY the rotor will end up pointing in the same spot. If not you may have to re-stab the pump with the shaft turned a tooth one way or the other.

 

[67Beast]

The last time I had to do one, I marked a tooth on the pump against the housing so that I could orient it once it was out of the housing. Then just matched the slot on the new pump and marked that tooth and slid it back in with no problem. Maybe I was just lucky, but it was no problem and timing was spot on.