i have a flathead V8 in my 50 ford and i have been told a differnet recipe on how to care for them from so many people. some people have said put a zinc addative in the oil, some have said run 91 gas, some have said run water with oil for coolant. add mystery oil add lucas products etc etc. What gas should be run in a Flathead? What oil should be used? What coolant should be used? Should there be any additives (zinc?) etc Are there secrets I should know or little tricks? i WOULD LIKE A RECIPE TO RUN A FLATHEAD AND MAINTAIN IT THE BEST I CAN. i DID A SEARCH ON HERE AND DIDNT FIND EXACTLY WHAT I WAS LOOKING FOR ANY HELP WOULD BE GREAT!!
Flatheads have, and are, run on every combination of oils and coolants you can imagine, and eery one of their owners will swear theirs is the only way to run one. When it comes down to it, any good oil will work. 50-50 antifreeze keeps the corrosion down, and zinc additives are good for any flat tappet engine. No deep dark voodoo secrets as far as I know! I have been told that multi-viscosity oils will build deposits on cast steel pistons, making them drag on hot starts. Never figured out if it's true, though I have torn lots of older engines down with a yellow varnish on steel slugs.Maybe...?
Flatheads are low compression engines so they do not need high octane gas. I use oil with zinc just as added protection, but I think a well broken-in engine would do as well without the zinc. Regular green antifreeze in a 50/50 mix seems fine to me.
Turn the fan one full revolution by hand, and look for a screw on the hub. If yours has the screw, remove it and fill the hole with whatever motor oil you choose, or 30 wt. I like Shell Rotella oil. It has the zink you need, and its available anywhere. Run 87 octane if the motor is stock, or 89 if it has higher compression. If you live where overnight freezing wont happen, water with a water pump lube is good. I ran a good quality green anti freeze in mine and changed it every three years.
My take...any modern oil and also gear lubes will be vastly better than the equivalent from 1950. Follow owner's manual on weights and go to it. Zinc...cam problems were practically unknown until the 1949 generation of GM OHV V8's came out. Flathead cams operate under very low spring pressures and lived forever on the oil available back then, lots of additives started going into the oil only because of chronic cam failures in the first few years of the modern pushrod v8's. If you are nervous, feed it some zinc for one change but I seriously doubt the necessity and I doubt that 1950 oil generally catered to this need. Oil will be greatly helped by adding a PCV(very easy on 8BA) and using 180 thermostats so water cooks off and nasty fumes exit rather than forming sludge. Stock byp*** filter will be fine. Use any good modern antifreeze, not for freezing in LA but for anti-corrosion. Change it occasionally as it can become acidic, use one formulated for aluminum parts if you have aluminum heads. Any gas you can find will have enough octane but a carbureted car on 10% alcohol will be slightly lean, maybe enough to need compensation. Also you MAY have fuelpump and carb troubles from modern gas dissolving parts and from the water that is inevitably absorbed into the alcohol. This is wait-and-see stuff... A biggy is the suspension, etc., underneath...lots of grease fittings with a hunger for scheduled maintenance. Again, owner's manual has locations and schedules, there is more info in the little service handbook. You probably need to buy a greasegun and learn this...most current mechanics have little grasp of this as all the modern stuff is sealed and is just run until failure and replaced. Religious adherence to the grease schedule can make your stuff last forever... (Books...probably all available in repro: Owner's manual is the MINIMUM. Good supplement is the "Ford Service manual, 1949-50 cars and F series trucks" which covers all maintenance and minor repairs. Beyond that there is the readily available 1949-51 shop manual ***ulation, which covers serious repair work.)
thank you guys! sounds like they are pretty tough engines(obviously if still running and around this long) i just wanted to make sure i was not damaging my engine by using wrong oil or wrong gas etc. i have replaced all fluids on the car and i replaced thermostats with fail safe 180s. i run 87 gas and i use 50/50 green antifreeze. i was told i should get just plain 30 wt oil with a zinc addative but right now I believe the shop put in 5w30 or 10w30 id have to check and i think its a blend of synthetic which I was told dont use synthetic. ill prob just drain and ad a better oil. what i have is better than the JET black clumpy **** that was in there. thanks for your advice.
Regarding the fan hub, put a couple of ounces of engine oil in the plug hole, then turn the hub so the hole is down and drain the excess off, there is a tube that allows the right amount of oil to stay inside. Don't just fill it, it will spray oil all over the engine for days until enough leaks out.
The conventional wisdom on oil seems to be this: if your engine has never been run with modern detergent oils, keep running a non-detergent. If it has been run with a modern oil, just continue with that. The trouble is that the detergents can dislodge some of the sludge built-up inside your engine and clog p***ageways. Maybe the previous owner will know what was used? You'll get all kinda of answers when you talk oil. Hard to find a really good quality non-detergent; if you go that route make sure it is rated SB and not SA.
The 49 engine we stuffed into our 32 roadster build came to us as an unknown. Pulled from a pickup the owner wanted to "update". No idea how many miles are on it. We change the oil about every 4K miles and put in the zinc additive. Once we got the carb sorted out and added mechanical advance, it goes great. Starts and runs every time. So far, so good...
Heavy duty, multigrade detergent oil has been available since 1951. 10W30 was the default choice in every gas station and dealership in the fifties, sixties and seventies. Chances are your engine has never used anything else. If your oil was very dirty you should take off the pan and s****e out the grit and sludge if possible. Otherwise, do 2 or 3 oil changes in rapid succession (like, every 1000 miles) to clean it out. Yours is a low compression engine, it will run fine on the cheapest regular. It will run better on 87 octane than it will on 92. The rule is, your octane should look like your compression ratio. Your engine has about a 6.5:1 compression and will run on gas as low as 65 octane. Do you have an oil filter? They used a byp*** filter. Oil change intervals were different back then. You change your oil every 3000 miles, the filter every 6000. With no oil filter, change every 2000 miles. Your engine does not need zinc additive. Any good brand of oil is fine. Shell Rotella 15W40 is a favorite but any good 10W30 is OK. Engines from back then need more maintenance in the way of oil changes, tuneups etc than new engines. Fortunately the maintenance is easy and cheap but you MUST do it regularly to guarantee a long trouble free engine life. Best thing to do is get the factory repair manual and owner's manual and go by that. Synthetic oil not recommended. It is good for your engine, but it has the habit of leaking through seals and gaskets regular oil does not. So it is good on a new engine, on your engine it may create leaks in places you didn't even know you had places lol.
When you are oiling the fan hub don't forget the generator. It has 2 oil cups, one at the front the other at the back. 2 or 3 drops at each oil change is all it needs. I like to use synthetic for this but motor oil is all you need.
. Synthetic oil not recommended. It is good for your engine, but it has the habit of leaking through seals and gaskets regular oil does not. So it is good on a new engine, on your engine it may create leaks in places you didn't even know you had places lol.[/QUOTE] X2 on this. Try running synthetic oil and your wind up with a huge puddle under the car. Ask me how I know this. The only other thing I can add is that flatheads seem to love running between 2100 to 2500 rpms. Depending on your gearing, this may be an issue if you run the interstates. I swapped out the original 3 speed for one with overdrive. This allows me to run 60 to 65 mph and still remain within the desired rpm range.
Re : Synthetic oil. I'll disagree a little here. About 4 years ago, I needed to change the oil on my '51. I had 10 quarts of Mobil-1 15-50 left over from my hemi racecar. It had worked so well there, that I decided to see how it would work in the stock flathead. Turned out real well; no more leaks than before, and the engine idles at 30 psi warm and 55 psi at highway speeds. Any oil that is over 50 weight has more than enough zinc for any flat tappet engine. The only down side is the price, but I had the first two years free, so I guess I'm doing all right so far.. Not to hijack this thread, but this brings something up that I've always wondered about. Given the conditions our (at least mine) flatheads operate under now, (no cold weather, no dirt roads, and frequent oil and filter changes), why wouldn't the stock byp*** oil filtration system work as well as or even better than a full flow system? From what I've heard, the byp*** filter has a finer filter than a full flow system. Under the almost ideal conditions most of us operate under, shouldn't filtering a portion of the oil better work out well? Even with the restrictor in the system, I would believe that all of the oil in the system would p*** through the filter a couple of times an hour at least. I change my oil and filter once a year in the fall and everything looks fine. I am building a mild '51 Mercury for my tub, and unless I can find a good reason not to, I'm keeping the byp*** system.
Well, start with the PCV and be sure to run the thermostats as stock...after wallowing in many flatheads I believe that sludge formation is the biggest oil threat, caused by water from combustion and poor ventilation and eventually growing acid enough to rust various baffles inside. The byp*** filter is a finer filter than normal sized full flows and will eventually catch a lot of crud. A lot of flatheads are running around without thermostats or with very low temp ones (Ford standardized the stats in 1933!), giving the engine a tendency to runn too cold when not under load. This encourages water ***ulation in the oil along with making the whole lubrication systen inefficient. Full flow conversion is impractical unless engine is fully apart but is something to consider at overhaul. Big, expensive engines use both... true full flow is pretty hard to arrange without a gigantic filter, and most full flow filters byp*** a lot when cold, when dirty, and at high revs...the combination of a FF and a byp*** filter would be a natural on a flathead and should keep the oil reallydamnclean...
The byp*** filter does work better than a full flow. At least, it gets the oil cleaner than a full flow. There is very little to be gained in going from a byp*** to a full flow filter. There is more to be gained by having some kind of filter, than having none. On an old engine where the byp*** was optional, I would install the byp*** filter if I could find one. I would not bother changing to a full flow. At highway speeds a byp*** filter will filter all the oil 5 or 6 times per hour.
As far as antifreeze goes, you should use it, or if you live in the south at least use some kind of rust inhibitor. The best antifreeze for your engine is the old fashioned green stuff not the new fangled orange or yellow. I also agree about the thermostats. If you have a good engine that is clean inside and a big enough rad you will not overheat.
On the 52 merc 255 engine we dissasembled to rebuild for the T that I am building the oil filter cannister had a tiney hole going into the unit. That hole was completely stopped up so no oil was being filtered, so I am going to filter all oil. If you use the old filter system the oil line going into it should be disconnected each time the filter is changed and make sure this hole is open or no oil will be filtered.
This can happen on an old engine that has not had the oil changed regularly. One way to check if the filter is working, is to put your hand on it after the engine has been running for 1/2 hour. It should be hot. If it is not, the filter is full of dirt or the line is plugged. If this happens your engine will still have lots of oil and good oil pressure, but the oil will not be filtered.
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