Oil used in my P-23 Engine

[James Williams]

Hi I’m new to the forum and I own a B-2-B 1950 dodge with a p-23 motor which has not been run since mid 1980's, I am doing all the needed things to try it out but have a question about oil.  What oil should I use to get it started, 10-40 detergent or synthetic or non-detergent and should I add some additives to it like Marvel oil, or ZDDP Zinc & Phosphorus I’ll start with that I expect to be asking much more as I get this truck up and moving again.  Thanks for any help.

[Dodgeb4ya]

I'd run any oil...30W would be fine. This is just to start it and see if the engine is even any good.

[Los_Control]

 

15 minutes ago, Dodgeb4ya said:

I'd run any oil...30W would be fine. This is just to start it and see if the engine is even any good. 

 

This is 100% correct. Before you drive it, you will want to drop the pan and scrape out all the gum.

To start and run mine, I put in Castrol 10-40. Then changed it again  after running it a few hours in the driveway

The gum will get sucked up into the screen, block your oil flow and ruin your  engine. But this gum will need some drive time and really heat up the engine to break loose and let the modern oil clean it.

 

35 year old oil makes for a really hard sludge. Do not skip the step to drop and clean the pan, After you determine what you will do with the engine.

Then when you are driving it, this question will create 10 pages of every bodies  personal opinions on oil ... right now just clean oil and start it.

 

 

 

[James Williams]

Thanks for the Information.

I did drop the pan and clean the screen there was very little to no sludge or gum in the pan just dark oil.  I was amazed at how clean everything looks, I took the timing chain cover off and it too look absolutely great the engine is nice and lose. I plan on taking the head off to look at the cylinders and see if any sticking of the valves has taken place before putting everything back and see what I’ve got.

[Los_Control]

Thats great news, these old engines ran non detergent oil and could cause issues down the road when adding detergent oil.

Might be a good time to run a compression check.

My first dodge flat 6, had 5 stuck valves in 5 different cylinders.

Pulling the head and oil and rotating the engine, had just one valve that was stubborn.

 

Big difference between 20 years and 35 years, my current project started right up and has one sticky valve after sitting 20 years.

Just saying, I might run a compression check on it first.

Maybe pull the covers off the side of the engine, oil the valves and get them working. No need to pull the head at this time.

 

My point is. When I pulled my head, I rotated the engine and valves would stay up and not return.

I used a plastic hammer and oiled and whacked em, but it was not the proper way.

I got 5 valves freed up this way, # 6 valve was really stubborn.

 

The real issue was stuck lifters.

You should remove the covers on the side of the engine, then oil the lifters/valve guides. Then  pull the head later if you think it is needed.

My engine sat in the field 20 years, and started /runs ... do a compression check before you pull the head.

If you have common stuck valves, will be this area to clear it.

You can run the engine and spray oil in the lifters with the covers removed.

You can not run the engine with head removed.

 

Or just pull the engine and do a rebuild. Pulling the head does not get you to the lifters to fix the stuck valves.