Pills
Junior Member
We have a 1930 Model A. I dropped the pan to check bearing clearances and, while I was in there, meticulously cleaned the sludge out of the pan, the valve gallery, and the inside walls of the engine with the hopes of going to a detergent oil to keep it clean. I asked around as to what oil to put in. Everybody I asked had a different opinion, frequently strongly held. With that difference of opinion and being an engineer-gone-bad, I had to go back to source documents and see what the facts are.
I went to the Model A Ford club of America and asked about lubrication. Excellent source! Under Detergent versus Non-detergent Oil, I found an answer by Les Andrews, who is the author we know and love of the ubiquitous shop manual. His answer, and I quote, "any detergent oil will work okay. If your engine has been using a non-detergent oil for a long period of time there will be deposit build up around the rings, valves, and cylinders, etc. Many times the wear in the engine parts is taken up by these oil deposits left in the engine. That is okay until you go to a detergent oil. After a couple of oil changes you will wind up with a real clean engine and the deposits that were taken up some of the where space is now gone so expect to start using more oil. This will only be noticeable if the engine has a lot of miles on it and sufficient wear. .…" I might add that the same might be true about dirt sealing the gaskets. Take the dirt away and the gaskets may leak.
The next question down was ‘Gas and Oil’. This unsigned answer, in the last paragraph, talks about using detergent oil. His last sentence is "I recommend using detergent oil and changing it every 500 miles which will give you a cleaner engine that will not wear the engine parts as quickly."
Another unsigned answer under ’Oil Weight’: "if your engine is clean as you stated I would definitely use 30 weight detergent oil. I have no preference as to brand. They're all far superior to the 1930 oils. By using detergent oil and changing every 500 miles (as I do also) the grime is held in suspension and when draining the oil so goes the dirt and grime. Most contamination comes from no air filter on the carb.”
In my quest to find the answer to my oil question, zinc was mentioned twice. To investigate that I went to Valvoline.com and to Frequently Asked Questions, Racing Oil. In the second topic they say, in answer to the question about older oils with zinc, "The anti-wear additive simply referred to as zinc by most car enthusiasts is actually short for zincdialky/dithiophosphates or ZDDP. Its primary role is to prevent metal to metal contact engine parts by forming a protective film. .…" Elsewhere, they imply that DZZP “will protect older style push-rod and flat tappet engines.”
In subsequent paragraphs they state that the ZDDP has been lowered "because phosphorus can poison a vehicle's emissions system, the zinc level is lower for current motor oil." Well, poisoning a catalytic converter is certainly not a problem on a Model A.
In subsequent paragraphs, they point out that the Valvoline VR1 Racing oils contain 75% higher zinc than the current motor oil "with a balanced additive package designed to work in both racing and street legal applications.”
I called Valvoline to find out if VR1 is a detergent oil. Got an excellent technician and he said yes, it is. When I told him it was for a Model A he IMPHATICALLY said that it should not be used in a Model A. The only oil they recommend is straight 30 weight, API rating SB, which hasn’t been changed since the 50’s. As it is before the advent of catalytic convertors it has the old levels of ZDDP. He further said that detergent oil should not be used in cars without an oil filter. What impurities you don’t drain out fall to the bottom of the pan as sludge.
Unfortunately, the only straight weight oil that I could find is 30 weight.
I called the Ford Motor Company. They were no help.
I ordered the Ford Model A Instruction Book 1930 (oval speedometer edition). On page 14 they recommend 40 weight oil for summer use and 20 weight for winter.
So there you have the facts and the expert opinions. It is a choice between better lubricity or a clean engine. (Full disclosure: You can get both in VR1 at about half again the cost or with Brad Penn oil at about double.) You can decide what you want to do. But as for me and our Model A, we are going to use 40 weight in the summer and a DZZP additive and 30 weight SB in the late fall and early spring. Where we live, the car is laid up during the winter.
Let the games begin!
I went to the Model A Ford club of America and asked about lubrication. Excellent source! Under Detergent versus Non-detergent Oil, I found an answer by Les Andrews, who is the author we know and love of the ubiquitous shop manual. His answer, and I quote, "any detergent oil will work okay. If your engine has been using a non-detergent oil for a long period of time there will be deposit build up around the rings, valves, and cylinders, etc. Many times the wear in the engine parts is taken up by these oil deposits left in the engine. That is okay until you go to a detergent oil. After a couple of oil changes you will wind up with a real clean engine and the deposits that were taken up some of the where space is now gone so expect to start using more oil. This will only be noticeable if the engine has a lot of miles on it and sufficient wear. .…" I might add that the same might be true about dirt sealing the gaskets. Take the dirt away and the gaskets may leak.
The next question down was ‘Gas and Oil’. This unsigned answer, in the last paragraph, talks about using detergent oil. His last sentence is "I recommend using detergent oil and changing it every 500 miles which will give you a cleaner engine that will not wear the engine parts as quickly."
Another unsigned answer under ’Oil Weight’: "if your engine is clean as you stated I would definitely use 30 weight detergent oil. I have no preference as to brand. They're all far superior to the 1930 oils. By using detergent oil and changing every 500 miles (as I do also) the grime is held in suspension and when draining the oil so goes the dirt and grime. Most contamination comes from no air filter on the carb.”
In my quest to find the answer to my oil question, zinc was mentioned twice. To investigate that I went to Valvoline.com and to Frequently Asked Questions, Racing Oil. In the second topic they say, in answer to the question about older oils with zinc, "The anti-wear additive simply referred to as zinc by most car enthusiasts is actually short for zincdialky/dithiophosphates or ZDDP. Its primary role is to prevent metal to metal contact engine parts by forming a protective film. .…" Elsewhere, they imply that DZZP “will protect older style push-rod and flat tappet engines.”
In subsequent paragraphs they state that the ZDDP has been lowered "because phosphorus can poison a vehicle's emissions system, the zinc level is lower for current motor oil." Well, poisoning a catalytic converter is certainly not a problem on a Model A.
In subsequent paragraphs, they point out that the Valvoline VR1 Racing oils contain 75% higher zinc than the current motor oil "with a balanced additive package designed to work in both racing and street legal applications.”
I called Valvoline to find out if VR1 is a detergent oil. Got an excellent technician and he said yes, it is. When I told him it was for a Model A he IMPHATICALLY said that it should not be used in a Model A. The only oil they recommend is straight 30 weight, API rating SB, which hasn’t been changed since the 50’s. As it is before the advent of catalytic convertors it has the old levels of ZDDP. He further said that detergent oil should not be used in cars without an oil filter. What impurities you don’t drain out fall to the bottom of the pan as sludge.
Unfortunately, the only straight weight oil that I could find is 30 weight.
I called the Ford Motor Company. They were no help.
I ordered the Ford Model A Instruction Book 1930 (oval speedometer edition). On page 14 they recommend 40 weight oil for summer use and 20 weight for winter.
So there you have the facts and the expert opinions. It is a choice between better lubricity or a clean engine. (Full disclosure: You can get both in VR1 at about half again the cost or with Brad Penn oil at about double.) You can decide what you want to do. But as for me and our Model A, we are going to use 40 weight in the summer and a DZZP additive and 30 weight SB in the late fall and early spring. Where we live, the car is laid up during the winter.
Let the games begin!
have fun with your A!