Good morning!
I don't log in here often but do read quite a bit so thank you all for years of great content and "spicy" debate. I'm hoping I can leverage some community feedback for an oil recommendation.
The vehicle in question is a 1959 Nash Metropolitan Series IV. For those unaware, these cars were manufactured by Austin or The British Motor Corporation Limited (BMC) under contract for Hudson/American Motors/Rambler depending on the year of production. It's a very British car in a classic American car disguise. The engine is a BMC B series 1500 engine so flat tappet cams, rope seals, the whole 9 yards.
I'm in the process of getting it road worthy again and I'm at the point where I need to fill the engine with oil and get it started. After a ruptured fuel pump diaphragm and a crankcase full of gasoline (with maybe 3-4min of run time at idle and no load, thank goodness) my plan is to flush the engine with something inexpensive (Traveller Fleet Oil from the Tractor Supply springs to mind) to make sure I've got all the fuel and other potential crud out of the system, then get it filled with something more appropriate.
A reputable Nash parts vendor recommends "For a rebuilt engine any modern conventional 10W-30 can be used; use 10W-40 for a non rebuilt engine. For any oils that do not have zinc be sure to use a zinc additive to protect the cam shaft from unusual wear" but cautions against synthetics & syn blends as they "tend to cause too may leaks." I believe the engine is original (I'm aware of hardened valve seat challenges and ethanol in modern fuels) and at the present time, it makes oil pressure but I don't have a dedicated oil pressure gauge on it. In the past I would have reached for Valvoline VR1 Racing 10W-40 but this appears to have been discontinued in the US. I have experience with ACVW 1600 engines and understand the need for additional Zinc in older, flat tappet cam engines so VR1 seems like a solid choice. As this is a vintage engine I would frankly be a little afraid of some modern oils with aggressive detergent packages, though the trip down "gasoline ally" has probably cleaned out anything that was ready to go.
A 50/50 mix of the readily available VR1 20W-50 & 10W-30 gets me pretty close to the 10W-40 recommendation, but I'd rather have something that is a "one and done" rather than playing mad scientist at every oil change (no offense intended to those who enjoy these activities.) The car is in Northern California so temperatures are moderate and really, the car will only be driven in nice weather. I expect very little highway use as the car was NOT designed for modern speeds and braking, but I'd like to not have to worry about oil selection in the future.
So, what modern oil would be most appropriate for this engine? Opinions and experience are most welcome. TIA!
I don't log in here often but do read quite a bit so thank you all for years of great content and "spicy" debate. I'm hoping I can leverage some community feedback for an oil recommendation.
The vehicle in question is a 1959 Nash Metropolitan Series IV. For those unaware, these cars were manufactured by Austin or The British Motor Corporation Limited (BMC) under contract for Hudson/American Motors/Rambler depending on the year of production. It's a very British car in a classic American car disguise. The engine is a BMC B series 1500 engine so flat tappet cams, rope seals, the whole 9 yards.
I'm in the process of getting it road worthy again and I'm at the point where I need to fill the engine with oil and get it started. After a ruptured fuel pump diaphragm and a crankcase full of gasoline (with maybe 3-4min of run time at idle and no load, thank goodness) my plan is to flush the engine with something inexpensive (Traveller Fleet Oil from the Tractor Supply springs to mind) to make sure I've got all the fuel and other potential crud out of the system, then get it filled with something more appropriate.
A reputable Nash parts vendor recommends "For a rebuilt engine any modern conventional 10W-30 can be used; use 10W-40 for a non rebuilt engine. For any oils that do not have zinc be sure to use a zinc additive to protect the cam shaft from unusual wear" but cautions against synthetics & syn blends as they "tend to cause too may leaks." I believe the engine is original (I'm aware of hardened valve seat challenges and ethanol in modern fuels) and at the present time, it makes oil pressure but I don't have a dedicated oil pressure gauge on it. In the past I would have reached for Valvoline VR1 Racing 10W-40 but this appears to have been discontinued in the US. I have experience with ACVW 1600 engines and understand the need for additional Zinc in older, flat tappet cam engines so VR1 seems like a solid choice. As this is a vintage engine I would frankly be a little afraid of some modern oils with aggressive detergent packages, though the trip down "gasoline ally" has probably cleaned out anything that was ready to go.
A 50/50 mix of the readily available VR1 20W-50 & 10W-30 gets me pretty close to the 10W-40 recommendation, but I'd rather have something that is a "one and done" rather than playing mad scientist at every oil change (no offense intended to those who enjoy these activities.) The car is in Northern California so temperatures are moderate and really, the car will only be driven in nice weather. I expect very little highway use as the car was NOT designed for modern speeds and braking, but I'd like to not have to worry about oil selection in the future.
So, what modern oil would be most appropriate for this engine? Opinions and experience are most welcome. TIA!