Synthetic oil

[Tudorp]

Anybody run Synthetic oil in their 239?

I'm thinking about changing to 20W50 Sythetic blend. Pros/cons?

[prpmmp]

Originally Posted by Tudorp

Anybody run Synthetic oil in their 239?

I'm thinking about changing to 20W50 Sythetic blend. Pros/cons?

Yes!! 1952 8BA, 5-30 Syntec(about 1000 miles on new build) http://www.bobistheoilguy.com/motor-oil-101/ Pete

[Tudorp]

Mine is a 53 8BA. To be honest, not sure when mine was re-built. I bought it from a guy that got it just to flip, so he didn't know much about it. I know it has had substantial work on it due to I do have a lot of reciepts from the previous owner that shows some work, but nothing that specific to total "rebuild". My motor runs great other than a slight lifter tic. But, I just want to change to 20W-50 in it, and thinking about going with a Synth blend. Think it will just help smooth things out, and might even remedy that lifter ticking.

Originally Posted by prpmmp

Yes!! 1952 8BA, 5-30 Syntec(about 1000 miles on new build) http://www.bobistheoilguy.com/motor-oil-101/ Pete

[prpmmp]

Originally Posted by Tudorp

Mine is a 53 8BA. To be honest, not sure when mine was re-built. I bought it from a guy that got it just to flip, so he didn't know much about it. I know it has had substantial work on it due to I do have a lot of reciepts from the previous owner that shows some work, but nothing that specific to total "rebuild". My motor runs great other than a slight lifter tic. But, I just want to change to 20W-50 in it, and thinking about going with a Synth blend. Think it will just help smooth things out, and might even remedy that lifter ticking.

I also use a zinc additive!! Pete

[Ol' Ron]

20/50 is the wrong move for these engines, hard on the oil pump and bearings run hotter. Ford spec. 10 winter, 30 summer for a reason. The best symthetic would be a 5/20 mix. the only thing 20/50 does in make the oil pressure gauge happy

[Tudorp]

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What do you think about Royal Purple? 5-20 isn't too thin? especially in summer?

[rotorwrench]

I've found synthetics to work wonders on modern engines with computer controlled fuel injection but the catch 22 for me is that I'm still going to change the oil every 3000 miles max on the old carbureted engine so it's kind of an expensive lubricant to chuck away that often. There is no magic lubricity to synthetic oil other than it won't burn when a little of it passes by the rings. It just vaporizes & passes out the pipe. Unless you have a full flow oil filtration system to keep your high dollar oil cleaner, I'd consider synthetics to be a waist of money.

[Ol' Ron]

Good point!!

[40ford]

Why take something simple and turn it into a complication?Been running flatheads with 30HD oil for 35 years with no problems!Just change with new filter regular and move on to other things. Sorry,just my 2 cents! (Walmart Super Tech 30wt. HD,nothing fancy)

[325w]

Royal Purple guy says if you have a little leak on 30w you'll have a bigger leak on syn blend

[Binx]

Either way you go, smell your oil when you put it in. After 3000 miles drain it out and smell it again and it will smell like fuel. Raw fuel is always slipping past rings and diluting the oil. Go expensive or go cheaper, but the result is the same.

Lonnie

[Ol' Ron]

Good reason to tune your engine properly, less gas in the pan.

[josh1331]

VALVOLINE VR1 10/30 has more zinc then other oils. No need to go 20/40 or 50 or to add zinc. It's on the web under VALVOLINE OIL. ITS CLASSIFIED AS RACING OIL WITH GOOD AMOUNT ON ZINC .JOHN

[JWL]

I like 20-50 oil in engines with mileage and 10-30 in tight engines. I like Valvoline Racing for break-in. Regular Valvoline after break-in. I never get enough mileage on an oil change to justify more expensive stuff.

As an aside, if you think 20-50 oil leads to wear or higher temp bearings I suggest you read the report from the S.A.E. titled THE RELATIONSHIP BETWEEN OIL VISCOSITY AND ENGINE PERFORMANCE.

[Cecil/WV]

Quaker State has an oil out called "DEFY" that they have come up with for flat tappet engines with Zinc added. Walmart for under $16.00 for a 5 qt jug. It's a synthetic blend, but I don't know the viscosity. One of our members showed it to us last week at our club meeting. Google Quaker State.

[Tudorp]

Not quite sure what ya mean here. Correct, but I never said anything about fuel in my oil. That's not a problem with my motor. Actually, there isn't a problem with my motor, just this will be the first oil change since I bought it, and being new to flathead v8, want to hear opinions on best oil I should use in it..

Originally Posted by Binx

Either way you go, smell your oil when you put it in. After 3000 miles drain it out and smell it again and it will smell like fuel. Raw fuel is always slipping past rings and diluting the oil. Go expensive or go cheaper, but the result is the same.

Lonnie

[Cecil/WV]

Quaker State Defy is 10w30. I'm not endorsing this oil, just letting everyone know its available. Just another choice.

[rotorwrench]

Carbureted engines always have more fuel traces in the oil just due to their inefficiency. If the power valve blows out or the bowl starts to leak, (and they always eventually do) then even more fuel ends up passed the rings or valve guides. It's just the nature of the beast.

In large aircraft, they used to have a dilution system that added fuel to the oil in the pickup hopper part of the oil tank so the engine would start in cold weather. This made for some short life oil but the oil was changed every 25-hours so it was no big deal.

[Tudorp]

I just checked this oil out. Sounds like this is the way to go. Has Zinc already in it too so no need for an additive. I think I'm going to pick up some of the 10W-40 of this oil. Thanks for that tip.

Originally Posted by Cecil/WV

Quaker State Defy is 10w30. I'm not endorsing this oil, just letting everyone know its available. Just another choice.

[19Fordy]

I have read that synthetic oil has a greater potential for leaking past gaskets if not used originally from the date of rebuild. Stick with Castrol 20W50.

[G.M.]

We have beat this oil thing to death for years. It seems the conclusion was almost any oil that feels slippery between your fingers worked in these old engines if changed frequently. I used Castrol 20/50 in all of my engines gas and diesel for over 35 years. I put a brand new WW11 engine in my 39 33 years ago, drive it harder than most and put over 120,000 miles on it. At 85,000 while changing the oil I felt the pick up screen move and pushed on it a few times and the tube and screen dropped into the pan. I removed the pan a brazed the tube back on the boss. The pan and underside of the engine was perfectly clean with not a spec of sludge. There was an area of about 3"s in diameter at the lowest spot of the pan next to the drain plug. This was hard and I suspect fine casting sand from the new engine. I scraped it out. I think I can find a picture of the bottom end I took. I have several expensive modern diesels and due to warrantee I used the recommended shell oil in them until I discovered the properties of Valvoline Cummins Blue diesel oil. This oil had all of the additives which I believe along with the experts can extend engine life. Seeing this I started using it in my old Fords. Now we will hear from some who say diesel oil is not good for gas engines but I don't buy it. The Castrol 20/50 up until a few years ago was diesel oil. I used the 20/50 in the new 39 engine from the original start up. This engine burnt some oil and got black in a few miles for 15 or 20,000 when it ran up near 200 degrees. After getting it cooled to the 170 range it stopped burning oil and the oil gets to a dark yellow. At 120,000 miles I never add any between changes. If your happy with and think your oil is the greatest continue to use it. If your looking to make a change read the makeup of the Valvoline Cummins Blue. G.M.

[Tudorp]

This is great info and what I'm looking for. Long term use of something that works. I'm new to the flathead V8, and have read, and read, and realize the subject has been kicked to death, hence the reason I am sort of confused as what works, and what don't. I've heard bad, and good about using 20/50 diesel oil, but good to hear from a long term user of it. Thanks for your info.

My biggest problem is I have a tad bit of OCD, and a chronic gauge watcher. Always have been. I just like to know what's going on under the hood, even with my daily driver Dodge Ram diesel. I monitor all gauges all the time. Not paranoid, just me. The issue I have that I have to learn not to let bother me is low oil pressure on the flathead. I know it's characteristics of these motors from what I hear. But damn, I am trying to fight my OCD with that, lol.

Originally Posted by G.M.

We have beat this oil thing to death for years. It seems the conclusion was almost any oil that feels slippery between your fingers worked in these old engines if changed frequently. I used Castrol 20/50 in all of my engines gas and diesel for over 35 years. I put a brand new WW11 engine in my 39 33 years ago, drive it harder than most and put over 120,000 miles on it. At 85,000 while changing the oil I felt the pick up screen move and pushed on it a few times and the tube and screen dropped into the pan. I removed the pan a brazed the tube back on the boss. The pan and underside of the engine was perfectly clean with not a spec of sludge. There was an area of about 3"s in diameter at the lowest spot of the pan next to the drain plug. This was hard and I suspect fine casting sand from the new engine. I scraped it out. I think I can find a picture of the bottom end I took. I have several expensive modern diesels and due to warrantee I used the recommended shell oil in them until I discovered the properties of Valvoline Cummins Blue diesel oil. This oil had all of the additives which I believe along with the experts can extend engine life. Seeing this I started using it in my old Fords. Now we will hear from some who say diesel oil is not good for gas engines but I don't buy it. The Castrol 20/50 up until a few years ago was diesel oil. I used the 20/50 in the new 39 engine from the original start up. This engine burnt some oil and got black in a few miles for 15 or 20,000 when it ran up near 200 degrees. After getting it cooled to the 170 range it stopped burning oil and the oil gets to a dark yellow. At 120,000 miles I never add any between changes. If your happy with and think your oil is the greatest continue to use it. If your looking to make a change read the makeup of the Valvoline Cummins Blue. G.M.

[G.M.]

On my post above it did not list the oil make up, I changed the attachment which you have to click on so it includes the oil make up. I like the molly and zink additives. Low oil pressure on any engine is not good. Low oil pressure in a flathead is from a problem not a natural event. They should have at least 8 to 10 idle and 30 plus at driving speed hot. Oil also cools the engine so more oil flow changes the oil faster between the moving parts. The biggest problem is the oil bypass valve and in some cases the oil pump gears or clearance between the bottom of the gears and bottom plate. On later model pumps it can be the bypass valve built into the pump. The guessing and part changing approach don't suite me. I want to find, see and fix the problem. I have stated many times on this site that I wouldn't put ANY pump new or used in one of these engines without testing it and seeing the results. The pump is to the engine as the heart is to the body. Several days ago I posted a picture and description of a simple way to test an oil pump so you know you won't need a pump transfer or replacement right away not to mention work, damage or premature wear on bearings and other parts with hardly any oil circulating. The engine can be spun on 12 volts with the plugs out, intake manifold off and a mechanical oil pressure gauge in the car or sitting on the floor. This will give you the oil pressure you can expect at driving speeds. If it is the front bypass valve you can shim the spring to the pressure you want. Any proper working oil pump will deliver over 60lbs of pressure and the bypass can be adjusted on the pump and or front valley valve to 45 or 50 lbs. If you have a pump and valley valve one must be set for a high spring pressure so the other one controls the pressure you want. G.M.

[Ol' Ron]

So the only way to solve this problem is to find someone that can put 120,000 miles on his Flathead wit 5/20 Synthetic oil, and compare them. I read an NASCAR artice a while back where the 5 wt oil ran cooler. The engines of today use this oil for a reason, Its better for the engine. The same reason we use better ignition systems and Fuel systems and we don't fly around in Bi-Planes any more. One thing I do know for a fact is the relief valve in an oil pump generates a tremendous amt of heat and with 20/50 oil it's doing just that.

[mrtexas]

If you do a search about oil the problem is not oil that is too thin, rather oil that is too thick, especially on startup.

http://www.bobistheoilguy.com/motor-oil-101/

[Tudorp]

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With all this said, what is the zinc % recommended for an oil in these motors? An oil I'm looking at is Castrol GTX 20W-50 which has %w .09 zinc.

[Shu47]

Don't cut me off at the knees but I was told that it was bad to run 5W oil on older engines (not specifically flatheads) because the tolerances and materials on the old engines were not designed for it. Don't remember where I read or heard it but it kind of logically makes sense to me. My opinion is if the oil is being changed every 1000 miles why spend the money on synthetic but if you are going 3K on a change then I probably would run synthetic.

[G.M.]

Originally Posted by Ol' Ron

So the only way to solve this problem is to find someone that can put 120,000 miles on his Flathead wit 5/20 Synthetic oil, and compare them. I read an NASCAR artice a while back where the 5 wt oil ran cooler. The engines of today use this oil for a reason, Its better for the engine. The same reason we use better ignition systems and Fuel systems and we don't fly around in Bi-Planes any more. One thing I do know for a fact is the relief valve in an oil pump generates a tremendous amt of heat and with 20/50 oil it's doing just that.

I can only tell you what happened on my engine, I don't deal with "what if's". The clearances and tolerances on todays engines aren't like the old Fords. The only reason I could see for a bypass valve in an pump causing higher heat would be it reduces the flow of oil through the engine, keeping the oil confined in the hot areas for a longer period of time. G.M.

[rotorwrench]

The OEM flathead valve springs have lower pressure than most all overhead valve engines so the need for more ZDDP didn't really come about until the later OHV engines started to have problems with cam & tappet wear. Later in the 50s & 60s they were making the engine with higher compression & horse power and made it even more important to use anti scuffing additives. You could probably run a flathead on castor oil if you had to but it would make you sick with the smell.

[Ol' Ron]

When rebuilding these engines we have the opertunity to take advantage os such things as Full floe oil filters and control the bearing clearances among other things such as adding dual exhaust, electronic ignition systems and other dudads. so taking advantage o fSynthetic oil as a method of improving the longivity of your investment ain't a bad idea. 5K between oil changes makes it cheep oil.

[Binx]

Originally Posted by G.M.

I can only tell you what happened on my engine, I don't deal with "what if's". The clearances and tolerances on todays engines aren't like the old Fords. The only reason I could see for a bypass valve in an pump causing higher heat would be it reduces the flow of oil through the engine, keeping the oil confined in the hot areas for a longer period of time. G.M.

Relief valves do cause heat from friction at the molecular level. I don't know how much that would affect a 50-80psi system but when I worked on aircraft hyd systems with 3000psi, a faulty relief valve would overheat the system very quickly.

Lonnie

[Rand]

I've been running Castrol 10w30 for over 20 years in my flatty...so far..so good. Randy

[Kahuna]

I run 5-30 Chevron oil. Good pressure, lotsa zinc and no leaks

[49r]

Originally Posted by rotorwrench

Carbureted engines always have more fuel traces in the oil just due to their inefficiency. If the power valve blows out or the bowl starts to leak, (and they always eventually do) then even more fuel ends up passed the rings or valve guides. It's just the nature of the beast.

In large aircraft, they used to have a dilution system that added fuel to the oil in the pickup hopper part of the oil tank so the engine would start in cold weather. This made for some short life oil but the oil was changed every 25-hours so it was no big deal.

I understood the fuel evaporated when the oil and engine heated up.

[Old Henry]

Originally Posted by Tudorp

My biggest problem is I have a tad bit of OCD, and a chronic gauge watcher. Always have been. I just like to know what's going on under the hood, even with my daily driver Dodge Ram diesel. I monitor all gauges all the time. Not paranoid, just me. The issue I have that I have to learn not to let bother me is low oil pressure on the flathead. I know it's characteristics of these motors from what I hear. But damn, I am trying to fight my OCD with that, lol.

Ah, a man after my own heart.
I watch the gauges too and, even though I believe that any minimal flow of oil is sufficient to get it where it needs to be, I still like to see the gauge read somewhere above the bottom. So, for engine starting temperatures above 60°F I use S.A.E. 40. It produces 60 p.s.i when first started and only drops to 30 p.s.i. when fully heated up. Any idle speed fast enough to keep the generator charging keeps the hot oil pressure at 20 p.s.i.

So, bottom line: If you like to watch the oil pressure gauge, experiment with different weight oils (I like straight over multi-vis*) until your gauge reads what you want then stick with it. (Of course, this is all based on having an accurate oil pressure gauge which may mean mechanical as per your previous thread: https://www.fordbarn.com/forum/showthread.php?t=134925)

*Here's a great discussion comparing straight vs. multi-vis oil and conventional vs. synthetic I learned a lot from: http://www.upmpg.com/tech_articles/motoroil_viscosity/

[Old Henry]

Originally Posted by Tudorp

With all this said, what is the zinc % recommended for an oil in these motors? An oil I'm looking at is Castrol GTX 20W-50 which has %w .09 zinc.

I've studied this "Zinc Question" at length over the years. The sellers of ZDDPlus had me sold on its necessity for the non-roller cam/lifters and I added their expensive product for a few years until I read a study that tested the effects of zinc on the stock flathead cam/lifters and proved that, because of the low valve spring pressure, no zinc needs to be added to any modern oils. They all have enough for the stock flathead valve spring pressures without adding any. (Wish I had saved that study. It was very good with photos of the cam/lifter wear surfaces and everything.)

[Old Henry]

Originally Posted by G.M.

Now we will hear from some who say diesel oil is not good for gas engines but I don't buy it. G.M.

Here it is:

Why not use oil rated for spark ignition, which flatheads are, instead of oil formulated for compression ignition, which diesels are? Doesn't make sense to me. Gasoline and diesel oils have different additive packages because the contaminants in the crankcase are different. With a gasoline engine you get a lot of moisture and tar and with a diesel the oil becomes acidic and will collect more carbon. It's always best to use an oil specially formulated to the type of engine for optimal life.

You will see things like "API SG or CJ" on the oil container, that means:

API = American Petroleum Industry
SG = Spark ignition (for gasoline engines), grade "G"
CJ = Compression ignition (for diesel engines), grade "J"

The second letter is the grade designator, in alphabetical order, and later = better.

I know I've said all of this before but I will say it again every time someone recommends that oil formulated for diesel engines be used in our flatheads.

But, having said all of that, I don't actually believe any particular oil is critical and have done just what I suggested two posts up - picked the viscosity that created the pressure I wanted to see on my gauge and that was it. I get the cheap NAPA brand conventional high detergent oil.

[G.M.]

Originally Posted by Old Henry

Here it is:

Why not use oil rated for spark ignition, which flatheads are, instead of oil formulated for compression ignition, which diesels are? Doesn't make sense to me. Gasoline and diesel oils have different additive packages because the contaminants in the crankcase are different. With a gasoline engine you get a lot of moisture and tar and with a diesel the oil becomes acidic and will collect more carbon. It's always best to use an oil specially formulated to the type of engine for optimal life.

You will see things like "API SG or CJ" on the oil container, that means:

API = American Petroleum Industry
SG = Spark ignition (for gasoline engines), grade "G"
CJ = Compression ignition (for diesel engines), grade "J"

The second letter is the grade designator, in alphabetical order, and later = better.

I know I've said all of this before but I will say it again every time someone recommends that oil formulated for diesel engines be used in our flatheads.

But, having said all of that, I don't actually believe any particular oil is critical and have done just what I suggested two posts up - picked the viscosity that created the pressure I wanted to see on my gauge and that was it. I get the cheap NAPA brand conventional high detergent oil.

Cheapest isn't always the best. You should have learned that by now on almost every repair you made on your car. Then when it fails you have more trouble finding the problem than most people, I guess because you know everything. G.M.

[Tudorp]

I really appreciate all the comments. Although it seems that it is still a well discussed issue. I have read, and still reading the links on oil science. It really is a science. Good points on all sides. A couple points also that don't make sense to me, but food for thought none the less. I think what it boils down to is what you are best comfortable with in your motor (regardless if the motor appreciates the same comfort). Bottom line is, I'm still confused.. lol.. I am not a mechanic by trade, but have built cars, and or motors and pretty good skills with that, but the science of motor oil has always eluded me really. I just always ran what I felt is best with good results so far over the years. Now with being new to the Ford flathead V8, started my inquiry all over again. My car has been running and sounding fine with next to no pressure on the gauge. However I haven't run it much since I only purchased it just before I stored it for the winter. Right or wrong, I like to see the needle actually do something. Sorry, it's just my OCD. That way, I at least know the oil pump is actually earning it's keep. This is what I have decided to do. I picked up this oil, and will add this zinc additive for additional security. We'll see how this pans out.

[flatjack9]

Go ahead and use the zinc additive if it makes you feel good. It absolutely is not needed. Too much zinc can also cause problems as I'm sure you have read.

[G.M.]

Originally Posted by Tudorp

I really appreciate all the comments. Although it seems that it is still a well discussed issue. I have read, and still reading the links on oil science. It really is a science. Good points on all sides. A couple points also that don't make sense to me, but food for thought none the less. I think what it boils down to is what you are best comfortable with in your motor (regardless if the motor appreciates the same comfort). Bottom line is, I'm still confused.. lol.. I am not a mechanic by trade, but have built cars, and or motors and pretty good skills with that, but the science of motor oil has always eluded me really. I just always ran what I felt is best with good results so far over the years. Now with being new to the Ford flathead V8, started my inquiry all over again. My car has been running and sounding fine with next to no pressure on the gauge. However I haven't run it much since I only purchased it just before I stored it for the winter. Right or wrong, I like to see the needle actually do something. Sorry, it's just my OCD. That way, I at least know the oil pump is actually earning it's keep. This is what I have decided to do. I picked up this oil, and will add this zinc additive for additional security. We'll see how this pans out.

I think you made a good choice. The 20/50 as posted by many over the years on this forum as improving oil pressure and working in their engines, the cleaning properties of Castrol and the zinc additive can all help the longevity of your engine. Even if zinc or other components may not be required on these loose, low compression, low valve spring pressure It can certainly help reduce friction and wear and will not show now, it may make these engines ALMOST perpetual. Go back to the 50's where engine failures in all make of cars was frequent compared to the same OLD engines now running, not to todays modern engines. As far as I see it the only difference between than and now is the oil. Attached is a picture of SOME of the sludge I removed from an original 38 engine that sat on the floor of a garage since the early 50's. I bought it several years ago, it never had the pan off and had standard bearings which didn't show much wear and not much of a ridge on the top of the cylinders. I doubt this engine had 30,000 miles on it. I compare this with my 39 engine installed 32 years and 120,000 miles ago with zero sludge and the only conclusion I come to is oil. My reason for changing to Valvoline Cummins Blue is from looking at the make up of the oil. I liked the molly and the zinc additive. It may be over kill for this engine as the Castrol has kept it like new all these years but if it helps a little over the long run that's what I want. Even if you don't have any intention of changing oil click on and read the oil article in my first post. I just thought of all oils being almost the same with a different label. There are different base oil that are used to start with and different additives in most. Like a lot have said almost any oil works in these engines but some may promote REAL LONG life which we may not be here to see the results. G.M.

[Tudorp]

I have always been the king of "overkill". My phylosophy has always been, "I would rather have it and not need it, than to not have it and need it.." I also know that too much of a good thing isn't always the best medicine also, so that being said, I am not going to use an entire bottle of the zinc. The oil has a little zinc in it already, but I am going to add 1/4-1/2 bottle of the additive as just a extra lump sugar with my coffee. In the next year or so you see my post whining and crying over a busted motor, well, we will all remember this post won't we?

[Old Henry]

Tudorp, please let us "OCD" guys know how your oil pressure goes with the 20/50.

[Tudorp]

Will do. I'm sure it will bring the pressure up which will make me happy. Time will tell if it also makes my flatty happy.

[Ol' Ron]

If yout prone to changing oil regulary, why not try a straight 40 wt oil and look at the gauge like The Prof said. As long s your running in the warm weather. Now if the gauge gets up to say 40 ro 50 lbs, on the next oil change try a straight 30 wt. I have a friend with a Ardun OHV 284ci engine and it doesnt show any pressure at idle, for the past 10 years or so. It's now down with a dead cylinder and it will be nice to tear it down and check everything. It wasn't knocking just No compression in one cyl.

It's not the destination, it's the journey.

[G.M.]

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Originally Posted by Tudorp

Will do. I'm sure it will bring the pressure up which will make me happy. Time will tell if it also makes my flatty happy.

You also mentioned a valve tick. This could be a slightly sticky valve. Get a Quart of Marvel Mystery Oil and while running drizzle a little down both sides of the carb. Put the rest of the bottle in the gas tank and drive the car. In 10 miles this should clear the sticky valve or valves. Put about a pint of MMO in every tank of gas. G.M.

[Tudorp]

Actually, that is a good point. I have always called that stuff Marvel Miracle oil. I generally do use that in the gas of my old cars, but I have to admit, I haven't in this Ford (haven't driven it very much yet), but now that you mention it, yeah, that'll happen... The "tick" to me does sound like a sticky lifter.

Originally Posted by G.M.

You also mentioned a valve tick. This could be a slightly sticky valve. Get a Quart of Marvel Mystery Oil and while running drizzle a little down both sides of the carb. Put the rest of the bottle in the gas tank and drive the car. In 10 miles this should clear the sticky valve or valves. Put about a pint of MMO in every tank of gas. G.M.

[billwill]

Im told if you change to synthetic oil from regular you will have leaks good luck.

[G.M.]

Originally Posted by billwill

Im told if you change to synthetic oil from regular you will have leaks good luck.

The oil he is looking at says "part synthetic oil" ???? G.M.

[40ford]

Originally Posted by 40ford

Why take something simple and turn it into a complication?Been running flatheads with 30HD oil for 35 years with no problems!Just change with new filter regular and move on to other things. Sorry,just my 2 cents! (Walmart Super Tech 30wt. HD,nothing fancy)

That is very true Will!This 'horse" has been beat to death over the years!Like the old saying says " You can lead a horse to water,but you can't make him drink" Sorry,my 2 cents again!

[richard crow]

don,t put sync. oil in a just rebuilt eng. use a reg oil for the first 2-3 thousand miles. once eng is broken in then make your choice.

[40ford]

I don't quiet get it?Why would you want to use "part" synthetic oil.Looks like to me you either use full synthetic or stay with regular.Think about it/what is the purpose???

[G.M.]

Originally Posted by 40ford

I don't quiet get it?Why would you want to use "part" synthetic oil.Looks like to me you either use full synthetic or stay with regular.Think about it/what is the purpose???

This "part synthetic" Looks like a advertising gimic to make it look like a more expensive oil and charge a little more than regular Castrol. I would call Castrol and or email them to find out just what "part" means and how much is "part". I got into this 4 or 5 years ago when they changed the SM or SJ or what ever ratings on all oils. Before that Castrol hard drive 20/50 was a diesel rated oil. They then changed the rating to a non diesel rating. I called a got some woman who wouldn't give me a straight answer. Her only comment was you have to use the new diesel oil on diesels. I emailed her 8 or 10 times and she would never answer my question "was the old oil equal to the new oil. Finally I made and sent a 10 question yes or no questioner and the results were yes the old oil is equal to or as good as the new oil. The old oil bottle had a red cap and the new cap was slightly orange/colored red. This is how I discovered the new oil. Walmarts puts all of the oil in loose quarts on the shelf. I was gathering a case of loose quarts and the last 2 bottles in the rear had the old red caps. Plus the SJ/SM ratings was changed. Pretty strange the oil that was good for diesels for 25 years and was the same oil other than the bottle was no longer good for diesels. Maybe with all the new high powered higher RPM tubo diesels the engine manufactures required different additives?? G.M.

[Paul Dobbin]

While I don't claim any expertise, I can tell you what I've done for over 40 years with all my flathead motors. Especially helpful to me when I don't know the history of the engine.
#1 I never use synthetic oils, because I think they are blended for higher compression engines and would tend to leak past these low pressure flatheads (Mine are mostly 221's)
#2 The lower the compression ratio test, the heavier viscocity the oil.
#3 My basic oil is 20/50 HD unless its a brand new rebuild with high compression, then I use the S.A.E. 30. I like the 20/50 to keep the oil pressure up and leakage down.
#4 For the high milage originals I use a straigh S.A.E. 40.
#5 For the really low pressure 35 Pickup I use S.A.E. 50 Racing oil. It loves it!
I alway use HD and change it annually, not according to mileage. Even our Glidden Tours
don't exceed 3000 a years do the calendar is the best determinate.

[Drbrown]

A few cents here .... We have relatively cold winters in northern upstate NY, 2 hrs south Montreal CA. My flattie gets a 15 mile or so drive in the city-country about once every two weeks during the winter to keep it limbered-up, but only if the roads are bone-dry. Has about 35,000 miles on its rebuild. I use good brand of 10w-30w regular detergent with a little zinc added, change it every 3,000 m (no filter), and it stays reasonably clean. Consumes not more than half quart in 3,000 and no oil leaks. I think it has an 80 lb pump because my add-on mechanical oil gauge reads 70 lbs at idle during startup and drops to abt 20 lbs when hot (175 degrees). Year-round I use a little MM in the gas tank and that seems to have quieted the valve train.

I can tell the prior owner drove it very little. Since owning it and running it more and more, the engine has become a little quieter.

Note about zinc: Based on a large older post I read, I understand most all oils have some form of zinc in them although the company's often have their own name for it. Dan

[green50]

Here's the oil to use, straight out of the bottle no need to add anything. Brad Penn 10W-30 Penn Grade Racing Oil "The Green Oil".
*Weight: 10W30
* This Brad Penn oil is a partial synthetic oil
* The old Kendall Green Formula
* Provides superior lubrication for any racing engine
* Increased concentration of “zinc”(zinc dialkyldithiophosphate a.k.a. ZDDP) provides
outstanding anti-wear/anti-scuffing protection for engines employing either ‘flat tappet’ or roller cams
* BRAD PENN Grade 1 High Performance Oils have been evaluated by a number of premiere camshaft manufacturers with tremendous success

Made in the
U.S.A