Packard Forum Index » Post-War (1946-54)

I removed my AC fuel/vacuum pump to service, and the two bolts that hold it to the engine block are cross drilled at the heads. Look like they are meant to be safety wired? They wasn't any wire on them at this time. I could see where they might want to back off from the cam action against the pump arm. This is from a 51 288ci engine.

I think the safety wire was a common practice on the pumps. My 47 has the wire and it calls for one thru 54. It may have been needed because of the wide heat insulation bushings and fiber washers not providing much for a lockwasher to bite into.

My '54 has the cross-drilled bolt heads also but there were no wires through the holes when I bought the car. I'm wondering how the wire was installed. Was the wire looped through both bolt heads and then the ends twisted together? The service manual doesn't show the wire(s) in any picture of the fuel pump.

Was the wire looped through both bolt heads and then the ends twisted together?

Yes.

There were some fairly elaborate patterns for things like connecting rod fasteners but for the fuel pump bolts any configuration that prevents loosening is all that is needed. No doubt many old time mechanics didn't rewire, just as they often discarded fuel pump heat shields and the like, with the old "not needed" comment to the owner.

Thanks, O_D. You've solved what was another Packard mystery for me. I have noted that those bolts do loosen slightly when I check them periodically. I'll have to torque them to spec. and then run a wire through them.

Run the wire so it pulls the bolt toward tight on each bolt. You can put a few twists in the wire to keep it stiff between bolts. Standard aviation practice, also used in racing a lot. You don't need to buy safety wire pliers, especially if you only need to do these two bolts.

navyaviation.tpub.com/14014/css/14014_116.htm

Thank you, HA52 for your detailed instructions. Now the procedure makes a lot more sense to me.

I can do pictures way better than I can explain things! Glad it helped

Thanks for the advice. I have a 1951 Beach Bonanza also. I have heard them called the Packard of Aircraft. Funny. That is what clued me to the safety wire, as it is fairly common practice on aircraft. I think the FAA schedule for safety wire twist is 8/10 per inch with stainless steel wire. I have forgotten the gauge. Was there supposed to be a heat shield between the block and the fuel pump on a 51? There was nothing when I bought the car. Everyone one the forums talks about vapor lock, which has never happened to me. Guess I should keep a spray bottle in the trunk just in case?

Thanks for the advice. I have a 1951 Beach Bonanza also. I have heard them called the Packard of Aircraft. Funny. That is what clued me to the safety wire, as it is fairly common practice on aircraft. I think the FAA schedule for safety wire twist is 8/10 per inch with stainless steel wire. I have forgotten the gauge. Was there supposed to be a heat shield between the block and the fuel pump on a 51? There was nothing when I bought the car. Everyone one the forums talks about vapor lock, which has never happened to me. Guess I should keep a spray bottle in the trunk just in case?