I have settled on 20/50 wt. with some addition of oil treatment to help with oil consumption.
The old gal uses about a qt. every 150 miles.
What have you guys found works best as far as oil weight and consumption is concerned?
SteveG
Mine does well with 10w-30
Thanx racertb.
I run about 25-30lbs. oil pressure.
When I've used up all the 20/50, I think I'll experiment with straight 30wt. or 10w30 and watch the oil pressure.
What's your pressure running?
SteveG
I do not know what the previous owner used, After I did my cam gear I used Shell Rotella 15 40, had some problems not picking up oil after the car had been sitting for a while. I changed to Honda GN4 10 40 motorcycle oil no more problems but I keep reading about multi viscosity oil foaming and without a filter it carriers all the debris it picks up. these old engines were designed for straight wt oil. so I changed to a straight wt HD 30, the engine is quieter oil looks good it's less expensive. I make a point not to dispute what brands and weight of oil my customers want to use but you can't beat what the manufacture recommends
Doug, I agree with your opinion. I think it also depends on the state of wear in any engine. Worn engines may require heavier oil.
What oil pressure does your car run at?
Are you using non-detergent 30 Wt.?
SteveG
Steve, I wrote down different readings at different speeds and temperatures, but can't find them. I will tell you that when the car is warmed up and idling, its very similar to yours. 25-30lbs.
My oil pressure hot at idle 25 to 30, Highway speed 35 are a little higher not quite 40. I use non detergent. That's what I was getting at about the multigrades. High detergent suspends the debris to carrie it to the filter non detergent lets it settle in the pan. Like I say I have learned not to tell anyone what oil to use, But you can't go wrong with the guy that designed it.
My engine re-builder told me to use 30 wgt non-detergent. Have used exclusively since about 1998. Oil pressure is about 28 on start up and will drop down to 24, 25 after 45 miles or so. I wish I knew how much it burns! The seal in the front leaks a bit; the oil drain plug drips slightly as well as some of the oil pan bolts. Appears oil comes out of filler tube and the crankcase vent tube also. Sounds terrible, but not that bad. Wonder what they were like when new.
Great info. guys!
I will try straight 30wt. when I run out of 20/50.
Amelia's engine is really worn and uses about a qt. about every 100-150 miles and would probably run with just about any oil!
She just keeps a runnin'.
SteveG
Not comparing apples to apples. Harley Davidson says a qt of oil every 500 miles is ok. Now go back 80 years, I have worked on so old stuff that has a total loss oil system. If your car is not smoking excessive I wouldn't be to worried about consumption. Just be aware. I had a customer several years ago would drive her Land Cruser until it started rattling and then she would add oil. Never check it just go buy sound. worked for her.