So the wife and I just became caretakers of the 1947 Nash 600 Slipstream Sedan that her grandfather bought new. He recently passed, and we're thrilled that the family chose us to look after it. The car has been in the family since 1947, hell we even have old black and white photos of her grandparents with the car when they were dating. It was repainted in the late 80's and reupholstered at the same time. The car arrived via flatbed yesterday. Body is in excellent shape, paint is good. There are some dents and dings here and there, but it's a perfect driver quality car. It needs a good mechanical going over to get back on the road. They had trouble with the cooling system and told me that it would run but that it had a tendency to overheat, so they never let it run long. Some electrical hackery has occurred over the years, but nothing irreparable. Somewhere along the line an electric fuel pump was installed to a toggle switch under the dash. I pulled the radiator and found a few interesting things. First off, the thermostat wasn't seated properly and was pinched between the head and housing leaving a crescent shaped hole where coolant could bypass the thermostat. Next when I drained the coolant, it appears as though it hadn't been diluted. It came out like pure coolant. Lastly, I think it's clogged, as I could get coolant to drain out the outlet hole, but when I turned the radiator over, nothing would come out the inlet. Plans are to get it roadworthy. I'd like to make it a reliable driver, go through all the systems, and restore it to semi-daily driver status (I work 3mi from home). I have a few questions for you gurus, as I've never owned anything this old. My experience is limited to 60's-70's vintage cars. -I'm assuming the valve seats aren't hardened, can I run this thing on 93 octane pump gas or do I need to ad some sort of lead additive or octane booster? -The original specs call for straight weight oil, is it okay to run modern multi-viscocity oil? -I know there are a million threads and a million opinions on the matter, but what's the general consensus on 12v conversions? -Can I ditch the oil bath air filter in lieu of a dry-element filter? -The radiator cap was missing, and according to this that I found on an eBay ad, my 47 Nash takes a "vented" cap and not one with a specific pressure rating. What's the deal here? Anyways I plan on updating this thread as I go and I'm sure I'll have a thousand more newb questions. I've found two really decent threads on Nash 600's of the same vintage on HAMB, which have had a lot of great information. Here's some pics of mine:
Welcome from Logan, Ohio! That Nash has made it thru the years in great condition. I would have the radiator checked and cleaned and flush the block real well to start with. Go thru the fuel, brake and suspention systems to make it safe and drive it to see what else pops up that needs attention. You are way ahead of the curve with such a good solid car to start with. Good luck with it, maybe I will see it around sometime!
My opinion on 6V vs 12v is this: the system was designed for 6 volts. (wires are correct size, etc) If you can't get it to work properly, it is a maintenance issue and switching to 12 volts is a lot of little problems, that doing the proper maintenance would avoid. Fix the 6 volt system. If you are starting from scratch on a hot rod, then 12 volts is better, because most modern components are 12v.
I get what you're saying about 6V. I just have no experience with 6V electrical systems, so it looks like the best course for now is to learn about them and fix what needs fixed with the existing system. First thing I'm going to do is search for a reputable local shop that can flush, clean, pressure test, and potentially re-core the original radiator.
I'm assuming the valve seats aren't hardened, can I run this thing on 93 octane pump gas or do I need to ad some sort of lead additive or octane booster? -The original specs call for straight weight oil, is it okay to run modern multi-viscocity oil? -I know there are a million threads and a million opinions on the matter, but what's the general consensus on 12v conversions? -Can I ditch the oil bath air filter in lieu of a dry-element filter? -The radiator cap was missing, and according to this that I found on an eBay ad, my 47 Nash takes a "vented" cap and not one with a specific pressure rating. What's the deal here? Leaded gas was available when your car was made but it was very low lead. Many engines came with hardened valve seats. I don't know about Nash specifically. In short, every car was made to run on low lead or no lead gas. Regular in those days was about 65 octane, hi test 70. Your car will run fine on the lowest octane regular available. In fact some people add up to 10% kerosene, stove oil or diesel to lower the octane and prevent vapor lock. This is not necessary but something to keep in mind if you have vapor lock troubles in hot weather. You can add some Marvel Mystery Oil, Redex, Bardhal or your favorite upper cylinder lube to the gas. It is not really necessary, but will prolong the life of the valves and rings by reducing wear. You do not need any lead or lead substitute. Modern multi viscosity oil is fine. Especially if you take off the oil pan and clean out the sludge. In fact chances are your car has used multi weight detergent oil since it became available in 1951. It was recommended for all cars, and was the default choice at every gas station and dealership since the fifties. The 6 volt system is fine. If it is not working correctly fix what is wrong. 12 volts is not a cure all. Try to change to 12 volts and you open a can of worms you will regret, and you will still have to fix whatever was wrong in the first place. One thing to keep in mind is 6v systems are more finicky about good connections. If your battery terminals or wiring connections are loose, dirty, or corroded that alone can be the source of problems. But, easy and cheap to fix. Just take the connection apart, clean with sandpaper or steel wool, smear on a little dielectric grease and replace securely. This will fix a lot of electrical faults. Also your original wiring has rubber insulation that tends to dry out, crumble and fall off after 50 years or more. This can cause problems too. A faulty generator, starter, or voltage regulator can be rebuilt by your local auto electric shop. If you live in a rural area there are lots of old tractors farm trucks and stationary engines still in service. In the city there is usually at least one auto electric shop or rebuilder that does the "vintage" stuff. Failing that there are shops online that can do the work. I suppose you could ditch the air filter but why in the world would you want to? All you need to do is pour out the oil and wipe out the dirt with old rags or cotton waste. Rinse the filter element with Varsol or kerosene and let drip dry. Do not blow it out with air, the air blast can make channels thru the filter medium. Put the base back on the carburetor and fill to the line with 50 motor oil. You can get it at any good auto parts store although they may have to order it. One quart will last you as long as you own the car. Pour a little oil into the filter to wet the filter medium and put it on. There you are done for the next 10,000 miles. At tune up time you can take the top off and check the oil in the base, if the oil is up to the line and the oil reservoir no more than half full of dirt, put the top back on, you are done. If it is more than half full of dirt, clean and refill as detailed above. On today's paved roads you can go at least 10000 miles before the filter needs service. It only takes half a pint to fill it up. So, your total expense is one quart of oil every 40,000 miles or more. The filter is BETTER and CHEAPER in service than any paper filter you can buy. They only stopped using them because paper filters are cheaper for the manufacturer (but more expensive for the car owner) and easier to fit under the hood. The oil bath is just as efficient and lasts longer. Your car had a vented rad cap and NO pressure. Many cars were unpressurized at that time, the first pressurized cooling system on Chrysler products was about 1951. Be sure to leave lots of space in the top of the rad for expansion. Otherwise your coolant will puke out the overflow when the engine is hot. As long as the coolant covers the tubes in the rad you are fine.
By the way very cool car. It seems to have survived the years in excellent condition. Service it by the book and it should last as long as you want it to. Nashes were known for pampering their passengers. They were comfortable, economical, had the best ride and the best heating and ventilation system in the industry. The 600 was the economy model. It was named that because it could go 600 miles on a tank of gas. 600 miles on a 20 gallon tank = 30MPG, about the most economical full size sedan you could buy.
One thing you SHOULD add is gas stabilizer. Today's gas can go bad in a year or less. In cars that are not used a lot, it is a good idea to stabilize the gas.
I can only concur about oil bath air filter, it's older, but build to be cheap and work in any kind of dirt, only drawback is you end up dirty when cleaning it. But that's a part of the game! The 12V swap is only a temp fix, the problem is if you had a problem within the 6v system, it will still be there when you have a 12v system. I've seen old fire engines running 12v on a 6v starter from its own battery. Then you have maximum power for your ignition even in the dead of winter. And upgrading to a modern charging relay will result in that the charging system is up to standard. As long everything else is to. Over here there available with a digital controller, only drawback is when it goes dead, no roadside repairs are possible to the relay. Drop it a little, go over brakes, suspension, ignition and carb, and you are golden for everyday driving. Best of luck with it and post some pic, from the road.
Thanks for the replies guys. I'd like to keep it as original as possible, so 6v electrics, oil bath filter and vented cooling system it is! As far as coolant, 50:50 mix? Or does it require something else? It appears as though the water pump is mounted to the side of the engine shaft driven by a shaft that comes out of the back of the generator. Interesting setup. There's so much to learn and absorb with a car of this era. So simple, yet so different from the other old cars I'm used to. The only modifications I would consider making at this time would be to take off the factory springs, and source ones that are dimensionally similar but with a slightly higher spring rate, and about 2" shorter. And perhaps get some wider steel wheels and more modern rubber. Vintage look, more modern performance. I'm going to get used to it in original condition before I go jumping into modifying it though. What the hell is this thing on the passenger side firewall:
Suggest you try it the way it is and see how you like it.50/50 coolant mix should be fine. Don't know what you mean about the springs but if you want it lower in the back, you could try 2" lowering blocks. The thing on the firewall, I don't know. Where do the hoses go? If the lower one goes to the intake manifold and the other goes to the vacuum wiper motor I would say it is an electric vacuum booster pump for the wipers.
SWEET!!! I love survivors! Don't do too much to it, in my humble opinion. I don't know what the heck that thing is. I do know that you can really improve the ride on an older suspension by using a stiffer shock and leaving the original springs. Just my $.02
You might get better answers here, at the AACA web site. They are more into originality although there is some crossover (some of us frequent both sites) AACA Forums
Regarding coolant, you can go cheap on that, it doesn't care for what it is in. The mix depends on your freeze point. Clean coolant can boil as well as freeze. But mix to 50/50 with plain water it goes to a freezing point of circa 30 degrees Celsius, and raises the boiling point to a 105 degrees Celsius. Unpressurized that is, opposed to 0 degrees freeze point, and 100 boiling. It should be change every 2-5 years, depending on manufacture claims. There's is a new product I've been dying to try out, but haven't come around to it yet. It's Evens water less cooling. It engineered for vintage cars but is also good for trucks and heavy machinery. It takes away with the water I coolant, it stops corrosion, and it can't boil. And last the life span of the engine. I have no commercials interested in this, but it should be good. They are approved for US army, Volvo and hydrema heavy machinery. .
I'll disagree with this statement. Multi-viscosity oils didn't become common until the mid-sixties, and even then straight-grade oils were still recommended for older cars that originally used them. You can use a multi-grade, but don't use anything thinner than a 20W40 or 20W50; stay far away from the common 10W30 and particularly any 5W oils. These motors were designed to use straight-weight oils, and will tend to run rather noisily with modern thin oils, as well as develop leaks. Truthfully, unless you're using it in cold weather (below about 40 degrees), I'd stick with straight 30W oil; it's still available and would be what was originally recommended. As to the sludge issue, if the car has been kept running all these years and has had periodic oil changes, it should be clean enough that modern detergents shouldn't knock a lot of crap loose. It probably wouldn't hurt to do a couple of quick oil changes to 'clean' it out and would be cheap insurance. As to the 6V electrical, checking/cleaning connections will pay dividends here, particularly look at any ground connections. Clean bare metal is what you need here, and using a dab of NoLox or Deox (found in the electrical section at any big box store) on your grounds will help. By the way, that's a really nice survivor!
Well Steve I actually worked in a garage in the mid sixties and I know what we did for oil changes. 10W30 was the default choice unless the customer specified something different. A quick web search reveals multigrade oils were available from 1951 on and were made for the new OHV V8s but were also recommended for older cars. Slightly cheaper was 20W20 which was also a detergent oil. We used it in older cars on request. We also kept straight 30 oil in cans and bulk oil in glass bottles on a rack. They were seldom called for, and were only bought by cheapskates driving oil burning klunkers. I don't remember ever doing an oil change with them. The kind of customer who bought that stuff didn't change their oil. We sold so little of the cheap stuff that we phased out the glass bottles by 1968. Chances are a car from the late forties or fifties has never used anything but multigrade oil since it became available. If the engine is not worn out 10W30 will be fine. If it is a beat up, high mile clunker thicker oil may mask piston slap and low oil pressure for the time being.
If you study some old owner's manuals from the forties and early fifties you will see they recommend 10W for below freezing weather, 20W20 most of the time, and 30 for hot weather meaning over 70. The only car maker that did NOT recommend multigrade oil in the fifties and sixties was VW. Their air cooled engines ran hotter than water cooled engines, and the multigrade oils of that time wouldn't stand up to the heat. Today's engines run way hotter than the engines of old, especially high performance and turbo jobs. The new oils will stand up to much higher temps. The only engines that might have trouble with modern oil are OHV V8 from the fifties thru the eighties especially high performance models. Sometimes they suffer valve train wear due to the lack of zinc. OHC and roller tappet motors don't need zinc, and neither did the flathead and low performance OHV motors before the early fifties. The zinc was only added after a rash of valve train wear problems on some of the early OHV engines, especially Studebaker and Chrysler.
Freeing at 30 degrees Celsius? I think you should 2x check that. That's around 90 degrees Farenheiht.
The car has only seen periodic use for the past 10+ years only being driven sporadically. It hasn't been used regularly in years. I did find a can of 10w40 in the trunk, so I'm assuming that's what was being used. Once I get it running I'll probably do a couple of quick oil changes as recommended above in order to knock the sludge out of the oil pan. I'll probably run a diesel oil due to the higher viscosities and extra detergents. The thing on the firewall is likely the vacuum motor for the wipers as suggested above. I also pulled the oil bath air cleaner for cleaning and re-oiling. It likely hasn't been oiled in years, and the oil level is way low. Speaking of oil, is there any trick to replacing the element in the oil filter? I took the top nut off but the lid won't budge. I was going to wait until my factory service manual arrived to tackle it... Thanks for all the help you guys, the more I get used to this car and work on it, the more I want to just keep it all original and drive and maintain it as it was meant to be back in the days. -MK
That engine was developed before multi-weight oil. It is designed with bearing and oil pump clearances for 30 weight oil in normal summer temps 40 to 80 degrees. (10 or 20 weight when colder, 40 weight for sustained driving above 80 degrees) a 20-40 or 20-50 oil is probably OK in it, but why not go order a case of the correct stuff and treat the old girl right! The water pump on the side of the engine was a common Nash, Rambler, and AMC thing, they might have been a Continental engine. They might have a packing gland on the pump that needs occasional service. (Tightening if it starts to drip around the shaft.)
The lid on the filters can stick. A few taps with a plastic hammer or wood block should loosen it up. If there is a drain plug on the bottom you can drain the oil out of it. Otherwise have a plastic bag ready. There should be a wire handle on top, it may be covered in sludge. Pull the filter out and drop it in the bag for disposal. You are supposed to use a suction gun to remove oil, then wipe out the sludge with old rags or waste. The new filter should come with a new rubber gasket and possibly a fibre washer for the bolt. Suggest you start by replacing all fluids. Coolant, engine oil, transmission, rear axle. Fill steering box with oil or grease. Lubricate chassis. Inspect brakes and repack wheel bearings. Check over all the rubber parts under the hood. Heater hoses, rad hoses, fuel lines, any that are bulged or hardened or cracked should be replaced. This may seem a lot of work but only needs to be done every 20 or 25 years, and will save breakdowns. Start with some short trips of 5 or 10 miles. If everything goes well, try some longer trips up to 50 or 100 miles. If you can drive 100 miles with no worries, you have pretty well got the bugs out. There may be some minor issues at first but once you start driving it regularly it should be pretty reliable. I don't want to get into a whole seminar on oil. But 10W30 gets its name because it is as thin as 10W when cold and as thick as 30 when it gets hot. Not that it changes, it has viscosity improvers to be sure it doesn't. It's the single weight oils that thin out when they get hot. So if you think straight weight oil is better than multigrade you are only kidding yourselves. Every car maker recommended its use as soon as it became available.
Thanks a lot for the info guys. I plan on taking my time, checking through all of the cars systems, replacing any worn components and going through a basic service of fluids and consumables. The speedometer is inoperable and I need to rewire the tail lights at a minimum. I'm sure I'll find more things that need fixed over time, but in all it's a very complete car in great overall condition. I can't wait to get it up to snuff and back into service. I remember a while back on this forum a guy DDing a late 40's ford with a flathead V8 and documenting it. That really stuck with me, and I'd love to be able to hop in this thing and drive it whenever I pleased. Along the way someone had purchased an electric fuel pump and wired it up via a switch under the dash. The stock fuel pump with the glass sight window on top is still bolted to the side of the block. Think I could rebuild it and do away with the electric pump? I'd love to keep it as original as possible. -MK
p.s. I can't find a replacement filter anywhere. Any ideas? edit: nevermind, pulled the lid and the filter that's in there is a Wix 51100. Available from Summit. Although it doesn't list 1947 Nash as a compatible model. Think it's ok?
It appears to be. Here's some basic specs you might find handy. http://www.carnut.com/specs/gen/nash40.html
Hi MK, First congratulations! What a fine car you got - The streamline back is just fabulous. The design of the rear fenders is as cool as it gets, none other period make had as cool wheel openings as Nash. I've been running same age Dodge since summer of 2007. The drive gear is stock apart from the B&W R10 overdrive (pulled from 1953 Savoy), which I installed an year ago. What I found, Mopar used hardened valve seats in their flatheads in the 1940's. I've been running my Dodge on "95E" gasoline, it's real crappy 95 octane stuff with 10% ethanol in it. The engine does not mind the shit, but I lost the original gas pump diagraph probably due to the ethanol... When I first changed the oil I put in 10W-40 multigrade - That was a mistake: First I noticed she started breathing in out thought the breather. Then I noticed I completely lost the oil pressure. I suppose if I would carried on with the multigrade I'd be loosing oil quite fast...? However, I changed to 40weight mineral and she's running just fine. Later on an Oldtimer told me that the valve guides and seats lubrication relies on mineral oil "vapour", he strictly forbid any syntethic oils in flathead engines, told that will not work in long run. 12V - no need for that unless you absolutely need to hook on a modern sound system...? Just remember the current is double cmpred to 12V, thus you need to use double heavy wires. With all connections cleaned, good wires and sound generator, you will not have any problems with 6V system. Rusty already answered to you for the oil bath air cleaner. I second to him. It's the real deal, do NOT ditch it. It does not restrict the air flow the same way as paper filters do. Unless you drive much on dirt roads, the oil bath it virtually maintenance free. Just clean out the dirt from the bottom of the cannister every 3rd or 4th year... p.s. I used to have a 1951 Nash Statesman for a couple of years. I suppose your car has the very same Nash L-head as mine had? The 1951 was 184 cid and it had also the B&W R10 overdrive in it. It actually gave me the kick to hunt down one for the Dodge as well. Have to say it's the best up-grade you can imagine to these 40's landyachts... All the best to you and your Nash - Enjoy travelling in style!
That statement I'll definitely disagree with. Multi-viscosity oils DO NOT 'thicken' when hot, they thin pretty much like straight-grade oils. You'll still see this misinformation posted by people who should know better. Don't believe me, check it yourself with a viscometer (available at paint stores) next time you drop hot multi-grade oil out during a change, then run the new room temp same-grade oil though the meter. Hot 10W30 when drained will run out almost like water, regular 30W much slower. Believe your eyes, not a bunch of gobbygook... Multi-viscosity oils are straight-grade oils with additives that allows them to meet the load-carrying requirements of a heavier oil. The first number is the actual weight, which is why it's followed by the 'W' for weight. The second number is it's load carrying ability. Now I'll admit this is much simplified, as they do add things like 'viscosity improvers' but these don't thicken the oil, they merely help it to thin not as much. The main problems with multi-grade in engines not designed for them are basically two; one, the thinner oil will creep past gaskets/seals not designed to seal that thin of a liquid. Don't be surprised if you develop leaks and also start burning oil. Two, because the oil is thinner and flows faster, those parts that depend on splash lubrication don't have as thick a lubrication film with a thin multi-grade. The main place this is an issue is the cylinder walls/pistons. This is why the air-cooled VW motors couldn't use multigrade; inadequate oil film meant scuffed pistons. You'll also find this as true on air-cooled motorcycles; if the 'base' viscosity is too low (as designated by the 'W' weight), the oil doesn't 'stick' to the cylinder walls enough. Now, if your vintage motor has been rebuilt with more modern parts, you can probably run a multigrade as metallurgy has improved over the years. But those old all-original parts were designed to work with the thicker oil film.
I've heard that the engine was rebuilt at one point in time, but I have no idea when or what constitutes a "rebuild" to some of the other non-mechanical types. I know that 10w40 has been used in this engine at some point in time and is likely what's in it now. Maybe I'll try my luck with straight-weight oil and see how the engine behaves. I probably won't drive it much if it's below 40F anyways, so I'll try the straight 30W oil and see if the old girl likes it. I'm sure I'll learn more about what works and what doesn't with this car as time goes by, but to start out, I'm going to stay as close to original spec stuff as possible. I'm going to get some fresh 50W for the air cleaner too.
Straight 30W is what it was designed for, you'll have no issues. I tried 10W30 in a '56 Ford I had and it immediately started leaking and ran much noisier. Back to 30W and the issues went away.... And this had been rebuilt.
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