Wednesday, February 21, 2018 3:17:09 AM

Flathead Engine Oil- Detergent- Non Detergent

28 days ago
#3888 Quote
Hi Again,
I know this can be a tricky question with many opinions. My 1950 flathead has been rebuilt, I have seen the pics from when it was bought. But, I am pretty sure it has been running 30w non detergent oil. It probably only has had 2,000 miles put on it in the last 20 years. It has the bypass filter on it. I have read that after a rebuild it is safe to use regular oil with zinc.

I am going to change the oil, what should I do? Would it be safe to switch to a modern "classic car oil" or would it get sludge up the engine?

Or could I put in 1 quart detergent oil and the rest non detergent and gradually go to full detergent?

Or should I continue using the 30w non detergent?. This car will be a Sunday around the town driver for now.

How many quarts are you using, I have read many things, but mostly 4 and 1 in the filter.

27 days ago
#3889 Quote
I use 20/50 non synthetic. From what ive read the thing to do is not run synthetic in an older engine. So I don't. But I live in southern Arkansas. It is pretty warm mostly. You need to get the Green Ford shop manual for 1949 through 51 cars. It has helped me in a lot of ways, My 49 2dr is all original 6 volt and I had never really worked with one. Now I have 2.It is rather easy to find on the Google.
23 days ago
#3892 Quote
I run regular 10w30 detergent oil in mine,it hasn't caused any problems. The owners manual said to sub one quart of kerosene for one quart of 30w oil in the winter. So I think a multi viscosity oil is fine.
22 days ago
#3893 Quote
unless you are using a full flow filter setup use only non- detergent.  Marlon
21 days ago
#3896 Quote
Thanks for the replies. I just found out here in California they don't sell 30w non detergent anymore. I think you have to buy the oil for air compressors. I think it might be the same, but had to change the label.
Anyone run a screw on oil filter adaptor for the flathead?

20 days ago
#3897 Quote
years ago, 90% of the oil sold was straight 30w, I sold many  since I work at a full service gas station..n.d. oil was mainly  used for small engines  after the brake in time. the detergent part is to help clean . and change, reg.
19 days ago
#3899 Quote
click on view all and on page 2 third subject down there is a
thread about engine oil - v8 flathead by Julian 5 months ago you might
want to check it out wrs50ford Southern Wisconsin
4 days ago
#3917 Quote
I switched over my whole fleet of flathead Fords to synthetic oil in 2008 when they took the ZDDP out of most oils.  Have not had any problems.  I get oil pressure quicker on cold starts and better oil pressure when hot.  I use Royal Purple HPS, 10W30, which is a API rated SL oil that still has the ZDDP additive.  I change it once a year in the older cars as they only get typically about 1000 to 2000 miles each year.