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How to Sort and Maintain a Prewar car

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The 38 Studebaker was ina barn for 40+ years well stored high and dry. It was covered in 40+ years of barn dust but no rust. Hauled it home washed it. Rebuilt the engine, Trans, rear end, brakes, front end and electrical (still 6 volt - average battery life has been over 4 years). We were going to paint it but thought let’s take the time and buff it to see what it looked like. It still has the original paint, some fenders are a little bare of black and the area below the gas cap is primer only but it’s still original. I did have to do the seats as every time you sat on it you took a lot of it with you on your backside. It’s my daily driver. It’s out of the garage at least 3 to 4 times a week. The only reason I drive our other car is if I’m in s hurry, if I’m in the 38 every stop has at least 15-20 minutes of guys asking questions about it which is fun but time consuming. I believe Edinmass said it best (I think it was his post on page 2 or so) all it took was time money and craftsmanship. I took the time, spent the money and was lucky enough to have very good craftsmen friends to help. It may not be the most classic vehicle to restore and own but it’s mine, it runs well is a ball to drive and my wife doesn’t mind that I usually have two blondes in the back seat ( my good buddies Gracie and Sophie) 

Buy and restore a prewar! 

Have fun

Dave S 



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21 hours ago, Tinindian said:

That is what they were built for.  Beautiful car I hope you have as much fun with it as I have had in the last 60 years with my Pontiac.

I am having a ball with it. I took it to a Hagerty show at the Indy track last year and got to drive the track at the end of the show. Porsche’s, vetted, mustangs, Lamborghini’s, muscle cars and my 38. I waited to be the last one in line. First lap 60 mph, 2nd lap 70mph and I’m maxed out. By the 4th lap I’m the straight away behind!  But wait there’s a turbo Porsche stopped half way thru turn 4. I move to the inside to pass him, I’m 75 to 100 feet away the driver sticks his hand out the window, waves and is gone in an instant!  Great laughter for us, the Porsche driver and the chase car behind me.  We did 15 laps pulled off and all compared the ride. I was the only one that did all 15 laps and never lifted!  Take that Porsche drivers! Pre war rules!  

Have fun. 

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  • 3 months later...

Given that we all have some extra free time, I thought I'd bring this thread back to life. We've had a fuel system discussion and a starting system discussion, which are two of the "big four" things that most people face when sorting out a car (the other two being cooling and ignition, although there are always a lot of little projects as well). So let's talk about cooling systems and how to get them healthy.


We've seen a lot of threads on this site with enthusiasts trying to figure out why their cars are running hot, but the cause is pretty consistent: rust and other debris in the cooling system. The fixes are not quick, they're not easy, and they're not cheap. In fact, fixing your cooling system is probably the single most expensive "sorting" project you'll face. But get it right, and you’ll never have to do it again and you won't worry on hot days. What's peace of mind worth?


Like the fuel system, there's no quick cure for your cooling system woes and no partial fix will make it work properly—upgrading one aspect rarely cures the problem and often means that any new component will eventually fail. Replace the radiator without cleaning the block, it's just going to fill up with trash again. Clean out the block without doing the same to the radiator and you won't get much extra cooling. Replace the water pump and it’s only going to be better at moving the trash around. Cooling systems are often all or nothing, which is why it costs so much to get things right. Is it worth it? Only you can decide whether you want to spend the money, but I, for one, like the idea of having a bulletproof old car that I can drive anywhere, anytime, in any weather. “Hot” on one of my cars is 180 degrees and that’s not by accident.


Unless you've recently hot tanked the engine block, it’s hard to know what's going on inside your cooling system. Chances are really good that there's a lot of rust. Even if you've been maintaining it properly, it's unlikely that previous owners have been equally conscientious. You can often get an idea of what's going on in there by simply looking down your radiator filler or pulling the hoses and poking around in the water necks. Check it out:


image-3954712586a.thumb.jpg.6fec92ec994a53d8e77e27860699daf3.jpg  20180707_164617a.thumb.jpg.98421247aad454d1980f081c2b3c164f.jpg
Looking at your radiator filler and water necks can show you a bit of what's
going on inside your cooling system. The radiator is a shot I got on the net,

while the water neck is my 1935 Lincoln when I first got it.




If your car is assembled and drivable, you're obviously not going to pull the engine to clean the water jackets. A bare engine on a stand certainly makes the job a lot easier, but it's not necessary. You should, however, be prepared to do some disassembly. Remove the radiator (you're going to clean it or re-core it anyway) and the water pump (this is a good time to replace it or rebuild it), and find a way inside the water jacket to clean it out. Expansion plugs are a relatively easy way to access the water jackets as long as the plugs themselves are accessible. Some inline engines have removable covers that will expose the water jacket, which is quite handy. If you have neither, you need to get creative—in these photos, I've removed cylinder heads to get access to cooling passages in the block. Whatever you do, remember that there's simply no substitute for getting in there and mechanically removing the rust. There's going to be a lot more than you expect. So step one is removing the loose crap.


Once you drain your cooling system, have a look inside your water
jackets and you'll surely find something like this. A slurry of
rust and coolant and bigger chunks that can clog radiators.


Use a variety of poking and scraping tools to really knock the rust loose; I have some engine cleaning brushes with long handles that work quite well, but my most effective tool is simply a stiff wire that I can bend into a variety of shapes. Use these tools to just poke and scrape all the rust you can. Use a magnet on a stick to grab the loose rust particles that are too big to wash through the passages.


471181714_2020-01-1812_46_21a.thumb.jpg.e2b735ac2ab2febd72cbbb499db2b6be.jpg  172132046_2020-01-1812_46_12a.thumb.jpg.eeded7bb2f5cc63159b3a4db984d110f.jpg  312787521_2020-01-1813_09_56a.thumb.jpg.b71829870697133238314babd46e2830.jpg

A magnet can help remove larger chunks, some of which could really cause problems.


Once you've done all the scraping you possibly can, run the hose through the upper water neck so it's travelling backwards through the cooling system and flowing out through the openings where the water pump lives (you removed it, remember?). It will also run out through the other openings you've used to get access to the water jackets. The water will be brown and chunky and you're going to be surprised by how much trash comes out with it. Scrape and rinse again. Do that until water runs through the engine and comes out clear. This will take a few hours and it’s going to make a big mess. Brace yourself.


1826473075_2020-01-1812_22_26a.thumb.jpg.e6369e07acc27bca16f4e00b6ab2c704.jpg  1929049837_2020-01-1812_22_40a.thumb.jpg.2c1808bfcb9c2a73bcdb0377e30c35e8.jpg

Run water through the block until it’s reasonably clear. It’ll be pretty gross at first. Note the
custom fitting I made for the side of the block, to which I can connect a garden hose.


Even with most of the big stuff gone, it will still be pretty
rusty in there. You've still got a way to go.


Still pretty rusty, no? The only way I know to deal with that remaining rust is chemically. Plug all the openings in the engine and fill it up with your favorite rust eater. Please don’t consider this a product endorsement, but Evapo-Rust is my preferred anti-rust agent. It works as advertised, it doesn’t attack other metals, and it’s environmentally friendly—it won’t even hurt your skin. It’s the consistency of water so you need to really soak the parts; brushing it on is not effective but soaking or using a pump to circulate it is. After a few days of chemical treatment, you should have nice, clean water jackets. If not, agitate it a bit, replace the solution, and let it soak until the rust is gone. It will take some time but Evapo-Rust should get the job done eventually.


It will work even better if you can keep it circulating. Using an inexpensive sump pump and basic hose fittings from a hardware store, I devised a system to move the solution through the engine so the rust that comes loose doesn't settle back in the block. I set it up to run backwards to help knock debris loose as it moved: in through the heads, down through the blocks, and out the water pump inlet(s). By running the pump for a few days, the solution circulates and eats the rust inside the water jacket and carries bigger chunks back to the bucket where it settles to the bottom.


20200210_102634a.thumb.jpg.cd9140a8b339f7604e025dd713adff4a.jpg  2-15-20-9.thumb.jpg.72678a05dac8a93e607d0b3bacdceab1.jpg
I set up a small electric pump (arrow) to circulate Evapo-Rust through the engine. Using

some custom fittings, I arranged it to feed backwards through the engine--in through the

water necks and out on the sides. It drained into the bucket and was recirculated. 

I also made custom fittings and used the same setup on my '41 Buick engine when I
changed the water pump.


Evapo-Rust is a chelating agent that bonds exclusively to iron, so it won’t attack other metals in your engine, which is good and bad—it’s harmless to all metals except iron, but that also means it won’t remove corrosion in aluminum heads or copper/brass radiators. It will dissolve the iron oxide that is both still attached to the block and any particles floating around, so you won’t have to worry about debris getting back into the block. If you use some clear tubing somewhere in your setup you can monitor the color of the solution—when it gets dark, it’s done and should be replaced. Best of all, the Evapo-Rust is so harmless that you can pour it down the drain when you’re done. It’s pretty amazing stuff. Again, not an endorsement, I’m just a very satisfied customer.


Evapo-Rust changes color as it works (once it's almost black,

it is no longer effective and must be discarded). Over the period

of about a week it is easy to see results. 


Inside of Lincoln block shows notable improvements. I think
all that remains is hard water calcification, which obviously
isn't affected by Evapo-Rust.


2079977933_2020-02-1218_39_27.thumb.jpg.3716af01afc4d44edd26ba354c90e838.jpg  399973278_2020-02-2915_21_20.thumb.jpg.23112770baacb947905d226cb254120b.jpg
Inside of Buick cooling passages show even better results. It's worth noting that
the Buick always ran ice cold and did not have cooling problems. It was still
pretty rusty inside and the radiator was on the verge of failure.


Once the rust is gone, flush it out with clear water and flush with compressed air to knock out any remaining debris. Then you can start reassembling everything—install fresh expansion plugs, button up the water jacket cover with a new gasket, reinstall the heads with new head gaskets, etc. This is a great time to clean and paint all those little related parts, too. If you can reach it or remove it, then go ahead and restore it. You’ll thank yourself later when your engine not only runs nice and cool but also looks like a million bucks.


865515220_2020-02-1218_39_27a.thumb.jpg.89703ddee509b104d83bce434977b5db.jpg  2-29-20-4.thumb.jpg.7be839ffaee0c4ad7e8afde4d2609e97.jpg
Why not clean things up as long as you're in there?


Edited by Matt Harwood (see edit history)
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The radiator is probably as full of gunk and corrosion as the block is—what, you think all that rust was just sitting there doing nothing in the engine? No, the water pump was surely washing it through the entire cooling system and unless you have serviced your radiator in the recent past, it’s probably just as messy as the block. The best way to get the junk out of there is by back-flushing the radiator. The natural flow of coolant through the system has been pushing it down into the bottom of the radiator and packing it tight. More of the same probably won’t knock it loose. But going backwards? Yeah, that can dislodge a lot of trash. You can try to flush it in the car, but that can be challenging and messy to other components.  It’s always better to use gravity to help, so pull the radiator and flush it from the bottom to the top, upside-down. You’ll be shocked by how much debris comes out.


In many cases, flushing may not be enough. You can try more Evapo-Rust and let it soak. That’s often helpful as it’ll eat any rust particles that have migrated into the radiator. But as noted above, the Evapo-Rust won’t touch corrosion on copper, aluminum, or brass, all metals that are used in radiators. If you have serious corrosion issues, bent fins, or leaking seams, merely flushing it may not be sufficient. At that point your best bet is to take it to the pros.


If your radiator is more than about 15 or 20 years old,

it probably looks like this inside. Hard water, old coolant
and other contaminants build up and block flow. This

radiator was still working, but the car "ran hot." Don't

assume that it's fine just because it's not overheating.


In fact, just remove the radiator before you do anything else and take it to the pros and let them do their thing while you work on other stuff. There's no point in doing things twice or wasting effort.


As with restoring gas tanks, the pros have tools and techniques that you don’t. While you can get OK results yourself, if you want it right, there’s only one way to get there: experts. Your local radiator shop can clean it, test it, fix leaks, and even install a new core to make it as good as new. If they’re replacing the core, make sure they’re specifically knowledgeable about old car radiators, because not all cores are created equal. Fortunately, there are dozens of different core configurations still available so they should be able to source something that is very close to what your car used originally.


Do not make the mistake of thinking that a modern core will be better—that’s not necessarily true. Flow rates, fin count, tube size, surface area, and more all contribute to the efficiency of the system and installing the wrong core can throw everything else off. Smaller, tighter, more numerous tubes might reject more heat, but your car’s water pump might not be able to move coolant thought it efficiently and cooling performance will suffer despite the new core. If your shop doesn’t know this kind of stuff, find one that does. It really matters. Yes, it’ll cost more to do it right, but I promise you’ll get better results in the end.


2-8-20-22.thumb.jpg.ba631dd2241b7b1bea3e21aa52825c6d.jpg  2-26-20-1.thumb.jpg.e3f88af5beebee83c13639a55cfe5435.jpg
What a difference $1100 makes. Radiator was on borrowed time. Brand new
core on original tanks gives it an OEM look. 

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Like the rest of the cooling system, the water pump is probably OK unless it’s not. You just can’t know until you get in there. Even on an engine that’s apparently circulating coolant, the water pump may not be healthy. Vintage water pumps are fairly simple and made from robust materials, so they’ll continue to work long after they shouldn’t. But unless you’ve recently rebuilt or replaced the pump, its health can be a question mark. If you’re truly interested in making things right, it shouldn’t be objectionable to remove it and have a look.


I bought a 1941 Cadillac a few years ago and it drove quite well. It had reportedly just finished a 700-mile tour with the previous owner and I drove it around town without incident for a few weeks right after I bought it. Nevertheless, it would get nervously hot at any speed above about 40 MPH and had a hard time keeping fan belts in place at that speed. No noise, no steam, and not quite overheating, just a few small clues that were hardly the loud, flashing, obvious variety. When we finally removed the water pump, we discovered that the shaft wasn’t properly secured to the housing and was slowly walking out of its bore, pushing the impeller against the housing and destroying them both. I was surprised that it was so quiet during its destruction, but the only real clue was a pulley that was a little out of alignment. I bet the previous owner had no inkling that any of this was going on and had taken the car on tour simply thinking that it ran a little hot… just like all old cars, right?


My Buick's old water pump actually looked OK. I'm going to clean
it up and keep it as a spare. 


RustyWaterPump.jpg.ef4ed8f058f5855a85834e7fd2ed1088.jpg  waterpump2.jpg.b439414cca97f6fba0712922aed754b1.jpg

It can always be worse. Both of these pumps were probably still 

moving water before they were removed.



If your water pump is quiet and coolant is circulating, then you’ll likely find it in reasonably good condition inside. The impeller should be intact and the bearings hopefully aren’t shot, but it’ll be rusty like everything else. Perhaps it has been leaking a bit, which is normal—on older cars the packing is designed to leak to help keep the shaft cool. On the other hand, the shaft itself might be pitted and a good seal might be impossible, also causing it to leak. How can you tell the difference?


Pull the pump off the engine and have a look. Evaluate the condition of all the important parts. Remember that during the sorting process, you’re aiming to make your cooling system invulnerable to heat, traffic, parades, and high-speed cruising. Don’t cut corners now. If the pump needs to be rebuilt, rebuild it.


There’s really not much you can do yourself to repair a water pump, so again, let the pros handle it. They’ll install (or make) a new stainless steel shaft. They may have replacement impellers if yours is a relatively common car or they can fabricate a new impeller if it’s something more exotic. The original packing can be replaced by a ceramic bearing and a modern seal that won’t leak and doesn’t need periodic tightening. In short, they’ll make it better than new. Spend the money and do it right.


Pitted shafts can be replaced with new stainless pieces.



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The final step is refilling your cooling system with coolant. There are many different preferences here, just as there are with motor oils, and none is right or wrong. My usual suggestion is to use whatever makes you comfortable. If you prefer straight water, go ahead and use that. If you prefer a mix of anti-freeze and water, that's great. I put permanent "waterless" coolant in my 1929 Cadillac a few years ago and it seems just fine. If your cooling system is healthy, the marginal heat exchange advantage offered by straight water should not be the dividing line between normal and hot. No, if your cooling system is right, you should have a very wide margin to work with and temperatures should remain stable under most conditions no matter what's circulating inside.


That said, it's probably worth exploring some options. None of this is 100% true in all cases, and surely others have had different experiences, but these are the most common choices ranked from most effective to least effective (and also cheapest to most expensive, which is a nice change of pace).


1.       Straight water (plus additive). Water is unquestionably the best medium for transferring heat. It absorbs it better and rejects it faster. However, water is also corrosive, particularly to iron, and most tap water has minerals in it that will collect in the various nooks and crannies of your cooling system. Adding some kind of conditioner or anti-corrosion solution to the water can minimize these negatives while keeping water's superior thermal transfer properties, and you're a fool if you don't use something to protect your cooling system. There are a number of products out there designed to lubricate and protect against corrosion; some brand names are No-Rosion, Sy-Cool, and various other additives available off-the-shelf. Everyone has their favorite, so I won't pick one here, but you should use something to minimize corrosion when filling your cooling system with straight water.


It's also worth noting that tap water isn't a great choice and most of the additive companies will suggest water that has been filtered through a reverse osmosis (RO) system. Distilled water is acceptable as well, although there are some experts who argue that the distillation process creates water that's so pure that it's very eager to pull electrons from your cooling system components as it tries to re-balance itself. RO water is readily available and I now use it whenever possible.

Note that water of any kind, regardless of the additives used, will not protect against freezing, so please take that into consideration when filling your system. Even if your garage is heated in the winter, a simple power outage can do a lot of damage.


2.       Water/anti-freeze mix. Typically the most common choice. The benefits are that most anti-freezes have built-in conditioners and lubricants that inhibit corrosion. They also offer freeze protection, and you can add water or even some other kind of anti-freeze any time without hurting anything. The downside is that ethylene glycol (the key ingredient in anti-freeze) is less effective at transferring heat and the greater the proportion of glycol, the lower the thermal transfer rate. The difference is not huge, but it can be significant in a car with a marginal cooling system. However, if your cooling system is in top health (which it should be at this point), it won't have any substantial effect on operating temperatures. In cooler climates, it's a reasonable trade-off given the freeze protection. You can also vary the proportion of water to anti-freeze to improve thermal transfer and manage the freezing point. For example, a 50/50 mix will usually provide protection down to -30 degrees. That's REALLY cold. If you don't expect to see temperatures that low, perhaps going to a 70/30 water/anti-freeze mix would be better; it offers improved thermal efficiency, reasonable corrosion protection, and protection down to 0 degrees.


Again, tap water is not recommended, but both distilled water and RO filtered water are acceptable choices when mixing with anti-freeze.


I'm not going to go into details on the OAT or IAT coolant debate, there's just too much to cover. I will say you can't judge coolant by its color, and if you have any concerns about the right type of anti-freeze, do your homework before filling your car, not after.


3.       Waterless coolant. Waterless coolant is a relatively recent invention primarily intended for fleets of big trucks where incremental improvements in efficiency can really pay off. Evans Coolant is the most common brand and its use tends to polarize enthusiasts. "Waterless" coolants are just what the name implies—straight glycol-based anti-freeze that does not need to be (and indeed, should not be) mixed with water. The advantages are that it has a 375 degree boiling point so you will never have to worry about boil-overs, and a freezing point of -40 degrees so cold weather is a non-issue. It provides great protection against corrosion (since no water is used) and lubricates the water pump. It is completely inert so it does not promote galvanic action and therefore corrosion in dissimilar metals is eliminated, and it won't harm "yellow metals" like babbit bearings. Since it doesn't boil, you can get rid of your pressurized radiator cap, which will take some strain off the components in your cooling system. The downside is that it is not as efficient as water at transferring heat, it cannot be mixed with any other coolant (including water, so if you're out in the middle of nowhere and didn't bring any extra coolant with you, you're going to have a problem), it’s slightly more viscous than water, and it's expensive at nearly $47/gallon—they recently raised the price by more than $10/gallon. Yikes!


As I mentioned, my 1929 Cadillac uses Evans Coolant and seems to work just fine. Yes, it runs about 10 degrees warmer than it did on a water/anti-freeze mix, but going from 155 degrees to 165 degrees operating temperature is not worrisome. I also suspect that the engine itself is cooler—the warmer coolant temperatures on the gauge suggest that the coolant is pulling more heat from the engine, not less. I do like that I never have to change it, I never have to worry about corrosion or freezing, it doesn't foam, and it is harmless to bearings should it ever leak into the crankcase, something that's not always true of regular anti-freeze. I should also mention that I probably will not use it in the Lincoln's V12 primarily due to price. At $34/gallon a few years ago, it was acceptable when I converted the 5-gallon '29 Cadillac. But the Lincoln holds nearly NINE gallons and at $47/gallon, I simply can't stomach the idea of nearly $450 worth of anti-freeze. I think they've finally crossed the price:benefit ratio threshold for most hobbyists, myself included. I'll probably use a 70/30 mix of water and anti-freeze in it, perhaps with some No-Rosion additive.



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I see Matt’s post and smile. Fact is most of the cars driving today have all the problems he has shown. After 40 years and countless cars, I just pull everything apart before I even bother to take it around the block. A few weeks of work in the shop is worth every second.......when you take your new toy out for a first few hundred mile spin, without tools, and make a round trip without difficulties. Time teaches the longer, harder way is the easiest in the long run. Learning the lesson is very, very difficult. 

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  • 5 months later...

I wound up getting a half gallon of Evans NPG waterless to test out. I put some in a plastic water bottle and put the cap on, when you shake it there is NO foam whatsoever. With regular antifreeze it foams like soapy water.


The NPG formula is for race cars, it has no ethylene glycol which is banned in race tracks. I'm guessing it's propylene glycol based but have no Idea. Propylene glycol is non-toxic, in fact they use it in hand cream and toothpaste and many other pharmaceuticals. The EG based Evans has no tolerance for water, they even make you purge your system to scavenge all the water out of it, but the PG based formula does NOT require you to purge the system, and it allows 5% water, and I'm guessing that if you run your car with this formula and 5% water from not purging the system, the heat from your engine will drive the water component out of it anyway after awhile, because the boiling point of the Evans is way higher that that of water.


The guy who runs the shop where I bought this says he recently bought a 1933 Ford pickup with a V-8. He says it foams like crazy and he can't keep the coolant in because it all foams out the top. But when I did the foaming experiment with him in his shop, with the plastic water bottle, he saw that it doesn't foam at all. He ordered 4 gallons for me and 4 more for himself, for the Ford!!



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