: how do I plug the holes in 472 / 500 head dor air pump lines? Also how to gut pump???

10-28-11, 12:20 AM
I just got a new to me engine for my hearse and it has the stupid air pump on it BUT it is broken and barely turns. Also the pipe between the heads is bent and broken in a few places...

1. How / what do I use to plug the holes in the front of the heads?

2. How can I take the insides of the air pump out so it spins freely and I can use it to still tighten the belt?

I already took the air pump apart and the inside turning drum does not seem to separate from the rest.

10-28-11, 10:39 AM
I did this so long ago, I forget how, but it is doable. The bearings on these units frequently fail, but availablity of the bearings is questionable in this day and age. You should be able to get pipe thread plugs at any hardware store, or if not check some of the stores that deal in hardware that have been in business for more than 30 years. The newer supply stores will not usually have them. The proceedure for rebuild may be covered in a SM for that year.

10-28-11, 06:08 PM
I don't want to rebuild it I want to "gut" the pump so it is only a pulley and nothing else.

The Ape Man
10-28-11, 06:32 PM
Dorman makes steel plugs which pound into the A.I.R. pump holes in the heads.

I've always changed over to the alternator/water pump crank setup. It spins the alternator a lot slower but modern alternators with more advanced alloy stator laminations and tighter tolerances seem to work fine.

10-29-11, 12:38 AM
What size plug is it? The parts store didn't know which one I need. I don't know how that set up you mentioned works.

10-29-11, 09:42 AM
I don't want to rebuild it I want to "gut" the pump so it is only a pulley and nothing else.

You state that it barely turns. You need the bearing to be free in order for the pulley to spin. You have one other option. Get a set of pulleys for a 425, then you don't need the pump.

10-29-11, 05:33 PM
11/16ths is the size of the plug you need.

11-19-11, 09:00 PM
where did you ever find a engine for your hearse at?

11-19-11, 10:58 PM
From someone on this board and from an unknown year xd. Still have to fix the power stearing.