Packard Forum Index » V-8 (1955-56)

All,

I'm currently building up my 320 engine. Seems to be going ok so far; I have the crank and camshaft in (with bearings obviously) which are prelubed with engine building paste. Also rear main seal installed. I left a slight amount of interference on it by cutting it with a box knife blade laid flat.

I noticed this rotating assembly so far takes 25ft lbs to move from a standstill, and 8 ft lbs to keep moving. Is this normal for a NEW seal, or did I leave too much interference?

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I used the fel pro. 2 piece neoprene

Yeah doing mine with the rope. With piston s in could barley move the. Crank

I would say. Unless you have the bearing tool to work rope down .sticks up to high.

You need a 2 1/2 inch diameter cylinder and I found that a 1 7/8 socket works perfectly for that. :)

To replace a piston, do I press out the old rod bushing then drop it in after heating the new piston head in water?

Unless the engine has had exceptionally long and severe use, the piston pin bushings are often reusable. This is because the Packard V8 rod is about twice as wide at the small end as is the norm for US V8s. There's much more bushing material spread over a wider area.

According to the Packard Shop Manual, a special burnishing tool is required to properly install new piston pin bushings.

jack vines

Thanks Jack. I realize I misspoke. Meant to ask if I can press out the piston PIN, then I just heat up the new piston and drop in the pin?

Got the valvetrain disassembled and cleaned. Pistons I hope to do this week along with the diff. Once pistons go in it will basically be ready to just bolt back together and drop back in, as the transmission is already good.

Radiator is in too, I plan to install it in the car before firing it up so that it'll just be hooked up to that cooling system. Fuel tank and lines, and transmission lines, need to be made and installed.

Edit: Also, I found that 15 of 16 tappets were replaced. I just disassembled each at a time, filled with oil, and squeezed it pretty good. All felt rock hard. Not very exact but hopefully they are all OK.

New pistons usually come with fitted pins and should slide in without heat. If they won't move by hand, then we put a steel plate on an electric hot plate and warm the piston. Not usually required with today's pistons and pins.

jack vines

Thanks. It's NOS, so my suggestion is from the manual.

Also, is this still an appropriate break-in procedure?

(Obviously connected to the cooling system.)

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