Re: TrevorK's 1955 Packard Patrician

Posted by Bob E. On 2019/8/15 14:06:38

Trevor,
I have done this a couple times recently. The short answer is that it is not hard, but cleanliness is next to godliness.

0. Read the service manual. It has a lot of good pictures for awareness of some of these steps and what things are going to look like
1. Pull carb (have a new carb to manifold gasket handy)
2. Remove intake manifold (ditto on new gaskets)
3. Remove valve covers and rocker arm mounting bolts (no need to remove the heads)
4. Remove lifter valley cover (my existing gasket ripped when I removed; so have new one ready)
5. Look at rocker arm tip to push rod interface. I had one where the rocker arm tip was very recessed possibly causing some interference as it rocked. It was due to the factory original arm not being properly ground so the recess was deeper than the rest. crazy.
6. With rocker arms removed, or pulled out enough to release pressure on the pushrods, you can push the pushrod up and out through the hole in the head.
7. While the pushrod is out, might as well roll on a flat surface to see if they are bent and need replacing.
8. Lifters come out by hand by pushing up from the cam interface, may need to use a wire with a hook on the end if you cant get them out easily.

(Note: good chance to look around, see if any pushrods are bent, etc) - Easiest to keep pushrods in the same position if you remove them as they are worn in to lifter. But if you are replacing lifters, it doesnt matter.

9. Carefully clean the lifter bore; It needs to be clean so the lifter will rotate. But this is also an opportunity to drop stuff down onto the cam lobes and below. So protect the cam. I covered the cam in a lint-free towel, then used a rag with brake cleaner on it to clean the bore with my finger, then wrapped a rag around a plastic bore brush and repeated. (this is a lot easier to do if the cam is out and you are replacing all the lifters, but maybe you don't want to go that far.
10. Lintless rags are important. Do NOT use paper towels or anything that can leave lint, etc in your engine.
11. Apply a little cam lube to base of new lifter as well as the top bore where the pushrod seats
12. Apply a little oil to the sides of the lifter bore and the sides of the lifter itself
-No need to pre-soak lifter in oil or anything like that you may see online.
13. Reassemble.There is no valve lash adjustment on these engines. The hydraulic lifters take care of all of that.
14. Use a Cam break in procedure which is essentially running at higher RPM right away to get enough oil moving around for a nice break in. I went between 2500 and 3000 for about 20 minutes.

Don't worry too much about it. I didnt know how to do this either and the great folks on this site helped me through it. Posting specific questions to the main 55-56 forum usually gets faster responses than in the project blogs. I think because not everyone reads the project blogs.

Good luck

-Bob