Loren

The tachometer I bought on eBay was $149 with $6.99 shipping. It comes fully assembled with housing and bracket. Three wires so it is easy for non-electricians to install. You'll need a hose clamp to install it on the steering column. 0 to 6,000 rpm which puts your cruise speed nearly straight up. ( on race cars you twist the instruments so that all the needles are straight up when normal ) It's an Autometer manufactured item modified by the seller to your particular needs. If you think you'd find a tach useful this one works. The old time racers believed that the more instruments you had in a race car the more marginal it was. The last one I built had a temp gauge, an alternator light and nothing more.

In college I had a 49 Special Deluxe Club Coupe. My Dad said keep it to 55 mph and it will last forever. I used to drive it from San Diego to L. A. often and it just kept going. My current 49 has a 3.73 rear axle and 205/75/15 tires all pretty standard out of the box. At 55 it sounded a little busy so I got an old Garmin GPS to check the speeds. The speedo was reading 55 when the GPS said 60! So I had the speedo serviced and was confirmed to read 5 mph slow. Along the way I installed an Overdrive transmission and that really quieted things down. I have read in these pages that the cruise speed should be about 80% of peak power rpm. The flathead sixes are listed at 3,600 rpm for peak power. So somewhere around 2,780 sounds about right. I found a neat little tachometer on eBay that is wired for 6 volt positive ground so I have that now too. Unfortunately the Coupe developed a coat of rust over the hood and front fenders that alarmed me enough to start a painting project, so I haven’t done much road testing lately. ( more on that in a separate post ) I think my car is capable of pulling the 3.54 gears I have on my shelf and I have some 235/75/15 tires I’d like to try as well. With the Overdrive I think a 70 mph cruise speed is possible. Before the Overdrive I kept it to 55-60. So that has been my process thus far.

I checked Rockauto because I just got some for the 49 Coupe ( I have a 52 Suburban as well ) $14 for Chinese made shocks or $17 for Monroe branded. They only had the FCS Chinese ones when I bought mine. They did not list fronts for the 52 Suburban. I next followed the post above and as near as I can tell the difference is in the bushings. I can tell you there is not much of a problem to change the bushings. Almost any auto parts store has the rubber bushings. So if that's what the hold up is get the 5752 Monroes or equivalent and change the bushings. That's what I will probably do for my Suburban.

There are kits which can connect to single circuit brake systems. They have a remote mounted vacuum chamber and can go anywhere. Moss Motors has a kit they make for English cars. The first time I saw this type of system was on a 1968 Volvo P 1800 sports car. The Volvo had dual circuit brakes and used two of them. If memory serves me it was a Girling manufactured system. I drove the car and it performed without any indication anything was different. Good pedal modulation etc. I suspect this type of brake boosters are still made. Perhaps a photo and a trip to a large brake rebuilder could put you on the right track. I seem to have a memory of a DeSoto with this type of system on it. The nice thing about them is you don’t have monkey around with changing pedal assemblies or anything else. A hydraulic line from the existing M.C. Connects to the booster and a hydraulic line back to the brakes, then finally a vacuum line. Plug and play.

Ethyl Lead ( the heavy grey muck ) will be seen much less in the future. My Dad used to ask me to collect some of it from time to time when I found it in the bottom of an old oil pan. He mixed it with grease to make Center Lube. He said you used to go to the paint store to buy it in tiny 1/4 pint cans but the feds stopped that. The company that made “Dutch Boy” paints was once known as The National Lead and Varnish Company and they offered it for that exact purpose. My Dad was a machinist who specialized in cylindrical grinding between dead centers. When you had centers that squeaked a little dab of white lead would stop it. When you think about the thousands of gallons of leaded gasoline that have to be burned in an engine to generate that much lead in the crankcase, it boggles the mind! The best lead came from engines made after 1965. The positive crankcase ventilation system sucked the water blow by out of the engine leaving a hard layer of grey lead and no sludge. There are wall charts in some automotive machine shops which show the various conditions you will find bearings in and what caused it. Dirt and metal particles that have done damage are mostly found imbedded in the soft metal of the bearings. The stuff you find in the oil pan can be harmless. I’ve learned not to get too excited by oil pan debris. It’s what the bearings have absorbed that really matters.

I went to the site and the first thing I saw was a Model A steering box. The last time I had one of those apart I was salvaging the steering shaft to weld on to a Gemmer box from an F100 (1952-56). That's the old time hot setup for a Model A (which are pretty awful). So I was pretty happy to hear that Plymouth used Gemmer steering gears. Right now the seal is leaking on my 49 which you can fix in the car. To do it you remove the sector then just tip out the seal. While you have the sector out you can check the preload on the steering shaft bearings. Being that they are tapered rollers you can tighten them up if need be. Gemmer boxes use paper gaskets which come in various thicknesses. To start you can peal off a thin one and see what reaction you get. By tightening the preload on the tapered roller bearings you will take out a lot of slop in the steering, but if you get it too tight the will be hard to steer at slow speed (parking) and it won't "spring back" after completing a turn. Next you can adjust the sector engagement with the worm on the steering shaft. Getting this right is a little tricky. If you screw the adjuster in it tightens the engagement. Too much and the sector "drags" at the ends of its travel too little and its sloppy when going straight. The best way to deal with it is not to move the adjustment until you need to. That is, when you remove the sector, take it out with the cap straight out of the box. Then you can slide the cap off the sector. Once you have a new gasket and the cap torqued down you might try turning the adjustment One notch tighter. Turn the steering wheel both directions and see what you think. If it gets tight at the ends, that may be too much. If when driving it is sloppy loose on center, it may be time for new gears. Whatever you do adjust the tapered roller bearings before you adjust the sector. I would never touch that adjustment without checking the bearings first.

I haven't done that job but I scan the Shop Manual for entertainment purposes. I did remember seeing the procedure for changing the boots. It is as Sniper describes. The manual offers a way to change the boot without removing the pin. The way it was done 70+ years ago was to lube the boot "with clean grease" inside and out, push it over the pin and pull it through the housing. Never having encountered "Clean Grease" I assume they meant un-used Grease. lol Speaking of the Shop Manual, I often find them lacking in description. Since Chrysler had considerable continuity of design between the divisions, I have found there are nuances in the different manuals that help me understand the procedures better...so I have all the manuals around the years of the cars I like. If the Plymouth Manual doesn't have the photo or description I'll pull out the DeSoto manual or Dodge or Chrysler. They all are a little different.

I have no doubt your Dad could do this! We used to say a car could drive in and you could tell what was wrong by the sounds it made. Then we would put it into practice. It was amazing how close you could come! Its all about how many cars of the same kind you’d see each day. Patterns become apparent. Cars are a lot more reliable now days and the mechanics less so. Because of this the mechanics rarely fix cars, they change oil & filters. They know where the OBDll plug is and they let a lap top guess for them. Soon you will ride in cars with no steering wheel or brake pedal. Your car will not be a symbol of freedom, it will be just another appliance. I for one appreciate the old time mechanics so much! A dying breed like shoemakers.

On my 49 Coupe there was only one key and it only fit the replacement ignition. I got some genuine “DPCD” key blanks which fit the doors & trunk but not the ignition. It seems the only replacements fit the switch but not the right key type. I removed the door lock cylinder a carefully filed a key to fit the tumblers. Later I found the proper way to do it. There are 5 tumblers (pins if you will) and 5 depths for each tumbler. Locksmiths of the day had sets of keys cut in the proper spot with the proper depth and labeled 1 through 5. They would take the lock apart and use the numbered keys to determine the combination. Then with their key cutter they could make the cuts by switching the numbered keys. Once the first key was made they could quickly copy as many as the customer wanted. In order for me to get the door and ignition keys the same I have to find a lock cylinder that fits the 49 key blank then change the tumblers. I know not many folks would bother but I will get it right one day. If you are in this predicament of needing an ignition cylinder just know the “Pentastar” keys are different than the “DPCD” keys.

A tapered rod journal will not cause a piston to be cocked. There is simply too much clearance for that. If the journal were tapered it would wear a band on the bearing insert. A bent rod will. Pistons do “rock” at the top of the bore (and the bottom as well) but only in the direction of the wrist pin action. Checking the rods is a job for the machine shop as they have the equipment to do it. You may think machine shops are sloppy (they are of course) but they know what they can get away with. You have to trust them and if you don’t like their work, find another. I have my favorites and ones I don’t care for.

I think your instincts are correct. They wouldn’t make lapping compound if it wasn’t useful. My only complaint is you only get two grades corse and fine. The fine isn’t fine enough to suit me but I use it anyway. I once worked with an Italian guy (he worked on Fiats and Lancias) when he did a valve job, he’d lap the valves and if they wouldn’t seat he sent the head out to have a new seat installed. The logic being that as the seat is ground it retracts the valve dropping the compression ratio. Okay. I can see the importance of that in diesel engines for sure. Not as bizarre as a 20 minute VW valve job through. Drop the engine, torque the heads (to check for bad threads in the case) remove the heads, put a rag on the bench under the exhaust valve, hold a deep socket over the spring retainer and smack it with a hammer releasing the keepers. Toss the exhaust valve, slip in a new valve, replace spring, keepers the tap with hammer. Re-assemble. Done. I saw it and it worked very well indeed, much to my surprise. It was my boss who did it too. He claimed he could do a valve job in half an hour...I watched and he did it in 20 minutes! Smoked two cigarettes and answered the phone once all in 20 minutes as well. What am saying is if those guys can get away with this kind of stuff, I wouldn’t worry or listen to anybody else. The valves seal with compression pressure. The valve springs only keep them in contact with the lifter. The proof I offer are the engines with desmodromic valve systems. One cam lobe opens the valve and another closes it, with no springs. The clearance is measured on both therefore compression pressure is required to fully seat the valve.

I bought a new Harbor Freight “surface preparation” tool and was grinding away on the hood. I was very surprised when I saw paint under the rust! It seems that where the paint gets thin the rust flows over the top of the surface. I wondered why the horizontal surfaces were getting this “carpet-like” texture. In dry climates the metal rusts where the paint goes away. In wet climates it flows over the remaining paint and expands. My next problem is getting it off the stainless steel trim. Can it be buffed?

Marc I do not envy you. A lot of agonizing. My problems are much simpler. I live at the beach, there’s a lot of fog and rain and I have to do something fast or a very nice original car is going to rust away! I don’t want to get involved with a complex paint system, I just want to stop the rust. I used to live in Northern Nevada and I go there often which is where Summit Racing has a warehouse, so it’s a natural for me. Low price, easy to use and best of all limited choices! I so glad I am not going through what you are. In 1949 Plymouth had 2 grey colors, one light and one dark. The oxidized grey on my car matches the only non-metallic grey Summit offers. Simple! It does not match the original color found in out of the way places….but who will know? If it is shiny it will be a major improvement.

I too am going to paint my own car. If you want to pay for PPG paint you can get a perfect match. However they are ridiculously expensive. I have decided to use Summit Racing’s single stage acrylic urethane paint. You won’t get exact matches to factory colors but the price and ease of use puts them in the running. My last project used the primer materials from Summit and a color match from PPG. The professional who did the job is who specified the materials and worked out great! I did use a paint supplier in San Diego for one project and found their stuff hard to get good results. I like the simplicity of the Summit paint and the price. If you’d like to compare go to their website, it’s very reasonable. From the reviews I’ve read they say the paint has a good shelf life but the hardener should be used within one month after opening. So buy the paint you need and the hardener you think you will use.

If a crankshaft has been ground there is a trick the machinist’s pull to take the bare minimum off the journals. On the main bearings they check the crank for straightness, then grind them. On the rod journals they measure the imperfections then alter the stroke to take the least amount off. Thus you could end up with a crank with as many different strokes as cylinders. So if you had a 0.010 deep ding in a rod journal to grind it on the original stroke would make the journal 0.020 undersize. Alter the stroke and you can have a 0.010 undersize journal. Not only does this method change the various strokes but it can change the timing as well. The good news is this is an automotive engine not a watch. You will never notice the variations.

My first choice was also Plymouth & Dodge’s first choice. The Bendix Stromberg model WW. They were used on the power pack option. These carburetors are super easy to work with and can be found nos for a reasonable price. I bought one new with the Overdrive switch bracket for $150. they will also fit an adapter so you don’t have to change the manifold. Linkage has to be fabricated or find a 1955-56 power pack donor car.

There’s cottage industry forming to rebuild the harmonic dampers for all cars that don’t have ready replacements. Basically the construction is a center with another metal part bonded to the center with a resilient rubber. Typically the timing cover seal leaks and rubber deteriorates causing the bond to give up. Or the rubber gets old and hard, cracks and falls out. The V-belts usually keep the outer part near by but I have seen them eat up a timing cover. Do you really need one? Judging by how many Plymouths didn’t have them, I’d say no. If I had a good one sitting on a shelf I’d use it but I would not go out of my way to get one and I’d make sure I had a metal replacement if it failed. Some engines have a “balancer” the flathead sixes are not one of them. In the true sense of the term it is a harmonic damper. The two masses bonded with rubber act to dampen the harmonics in the crankshaft. It does not counter act an imbalance. You can take a crank and ring it like bell. (It will buzz or sound dead if it has a crack) That’s the harmonics the damper soaks up. Slip the damper on and its noticeably quieter when you ring it.

This one of those things you learn from your 17 year old. He however has found that he is “over the hill” in video games because the 12 year olds can regularly beat him. lol The only video game I ever mastered was “Pong”. Considering the cost of the battery packs vs a power port & polarity adaptor, I think the battery pack wins. However, it does have a “cool factor” to have your GPS plugged into the lighter socket but only to folks over 60. The 50 year olds don’t use GPS to navigate anymore, they use their iPhone and a battery pack. I don’t navigate anymore, the spouse does that, I just drive. Much simpler. Easier to keep up with traffic than technology.

First 1952-54 Windsor brakes are 12 inch. That’s what I have on my 49 Plymouth. Second I used an old Garmin GPS while my speedometer was out for repair. I belong to the Model T Ford club and had found in their material that many members had figured out that chargers and adaptors have a voltage regulating chip. The target voltage is 5.5 volts. So they will work with zero problems on our cars. However, there is the positive ground vs negative ground issue. From experience it would be best to make up a plug/jack adaptor to reverse the polarity, rather than trying to do it at the lighter jack. The dash is chromed steel and if you aren’t paying attention just a little slip will pop the fuse (if you put one in).

It all depends on how its driven. If you are going race anything, you can break it. Some folks drive like they intend to break things. As Colin Chapman said of Mario Andretti, “That man could break an anvil” Chapman, it should be noted built cars that killed a lot of good drivers by breaking under stress. I understand Sniper’s point, the weak link in the 8.25 rear axle is not the axle shafts, it is the fact that it is undersized for the torque load anticipated. For serious loads there are bigger stronger axles available. The ones usually used for axle swaps in vintage Plymouths, ie Cherokee & Ranger are not on that list. Number 1 Ford 9 inch. It has the removable differential carrier like the MoPar 8.25 & 8.75 but for strength and a lower drive shaft hump it uses a “straddle mounted” pinion gear. Meaning the offset of the pinion to the ring gear centerline is so extreme it practically straddles it. This gives the 9 inch a lot more tooth contact and thus strength. That extra strength however comes with a parasitic drag cost. Number 2 MoPar 8.75. The 8.75 has the removable differential carrier but not the straddle mounted pinion. Thus it doesn’t have the parasitic drag. It isn’t as strong as the Ford but all things being equal you’d go faster with it. Number 3 Dana 44. Used in more cars than you’d believe! Doesn’t have a removable differential carrier, isn’t a straddle mounted pinion type. The guy who now owns Joe Walsh’s Maseratti is a friend of mine (the one he sang about “my Maseratti does 185, I lost my license now I don’t drive”) and so I’ve looked it over pretty closely. There lives a Dana 44 in those cars just like my International Scout! Clearly the MoPar 8.75 has some compelling advantages over its competition. Even this well designed axle can be broken with enough power and hard use. I am reminded that Plymouth used the Dana 60 in the Superbirds. Which takes us right back to the concept of not changing anything until you break it. Once you’ve proven you have the power and the difficult operation to break it, then you change it. The average guy in his 70s is not going to stress his car like he did when he was a teenager. We simply don’t want to pay the tickets (Jay Leno being a notable exception. I’ve seen him driving his 1912 Stanley twice the posted speed limit, with no seat belts and 1912 brakes!). So its back to the need vs want argument. If you need it there is no question but how do you know you need it? You gotta break it under use. If it is just something you want, then that is the justification. Engineers work on needs not wants.

Keyed tapered axles were used successfully for a very long time. If the parts are in good shape and axle nut is tight with a cotter pin in it, they are more likely to stay together than come apart. The Halibrand quick change axle Hot Rodders still use has keyed tapered axles. Its the taper that does the real work. The key offers added protection. In machinery tapers are used in lots of torque applications. Drill chucks for one. Jacobs the drill chuck manufacturer has their own spec tapers. The biggest complaint about the stock axle is that it requires a really good hub puller to get them apart. I like the design of the stock 8.25 axle but if you find you can break it, then the next axle MoPar made is the 8.75 and it is highly respected. It has the same excellent design, is much stronger (not that the 8.25 is weak, but the 8.75 is larger) and has lots of ratios and limited slip differentials. It bridges the era of keyed tapered axles and the flanged axle shafts, so if you wanted to look “Old timey original” you could. My thoughts on most things mechanical is that you don’t change anything until you find you can break it. Then strengthening one component will almost certainly lead to the breaking of others. The weak link keeps moving. The 8.25 axle was used clear up to 1956 and it was strong enough for the first V8s. If you have an 8.25 axle shaft out of the car take a look at the necked down area between the wheel bearing and the differential splines. Notice how long it is. If you look at a flanged axle shaft, look at the smallest diameter and how short it is. I was looking at a Dana 44 the other day and I swear the smallest diameter was less than 3/4 inch long. You don’t need an engineering degree to tell where that axle will break. That long necked down area was intentionally design to spread the torque load over the largest possible area. That’s a good design feature. I have to admit I haven’t seen a flanged axle shaft from an 8.75 but I haven’t heard of any breaking either.

Here’s a tip. in your photo you can see an arrow on the anchor bolts. Before you take anything apart, mark the shoes and mark where the arrow is. Since it is so easy with phone cameras take a picture as well. After you change the cylinder (s) put everything back the way you found it. Shoes in the same place and arrows pointed exactly as they were. This is the only way you can get the adjustment right without the special tool to center the shoes. You might scan the shop manual before you start to visualize what I am talking about.

Brake fluid is hydroscopic, meaning it absorbs water. Water is not good for brake systems because of rust and the fact that it boils at too low a temp for brake systems. The brown crud you see is the result of water absorption. If you catch the water early, you can get rid of it by flushing the brakes with alcohol (it’s listed as fuel and can be purchased in the paint dept.) then use dry air to blow out the lines. If you have a vehicle which has sat for years with water contamination, you might find it a better bet to just replace everything, hard lines, flex lines, master & wheel cylinders. I had a lot of experience dealing with water contamination as a dealer mechanic. Early SAAB 900s had a vent on both sides of the hood. One side was over the HVAC inlet and the other was over the brake master cylinder. The factory installed a plate in the hood over the master cylinder which directed rain and carwash water away. The two largest export markets for SAAB were the US and the UK so making one hood and two different covers made sense. There was never a problem with the cars until a body shop had to replace the hood. If they put a used hood on, no problem. If they put a new hood on, they usually forgot to transfer the plate over the master cylinder. Water had a direct route right into the master cylinder and the hydroscopic nature of the brake fluid drew it in. The inside of the master cylinder would develop rust pits in the bore and became junk very quickly. The rest of the brake system fared better and on stick shift cars you had to use the alcohol treatment there too because they shared the fluid reservoir. The factory recalled the cars to install a plastic cover over the master cylinder in case the hood was ever replaced and deleted (read scrapped) every replacement hood with two vents in the spare parts inventory. All new cars and spare part hoods soon came with one vent over the HVAC. The factory reps toured all the dealer used car lots for some time to make sure any used car there had the plate and the recall plastic cover. Since it was not a defect in the design it was classified as a product improvement and so the government never got involved.

I saw a friend of mine today who just bought a condo in Honolulu. He has a very active mind and has to be working on something all the time. He told me the auto parts stores don’t collect waste fluids there. The trash service supplies you with a box. The box has a plastic bag inside with absorbent shredded paper inside that. You pour your oil and or anti-freeze in the box seal it and put it you trash can. The trash is collected but in stead of a land fill it goes to an incinerator which makes steam to make electricity. Your waste fluids are considered fuel and not toxic waste because of the way they are handled and disposed of. I am not a climate change worrier but I do worry about garbage. I seriously doubt humans can influence the weather (good or bad) however the trash we generate is a clear and present danger because there is so much of it. I was really pleased to hear the islands have a system that works!

I have often thought about that rear bearing. If you wanted to restrict it, you could push in a thick roll pin from the cam side. Take a careful measurement of the bearing surface, check the manual for clearance, measure the cam and have it hard chrome plate to bring the clearance to the low end. Cast iron to cast iron bearing surfaces are acceptable but cast iron to hard chrome is better. You don’t have to get too fussy about that bearing as number 6 rod doesn’t share oil with another rod. A good automotive machine shop can align bore the block for an insert bearing as well. In a conversation I had with John Kilgore (who builds racing automatic transmissions) he stated that he saw no reason why you couldn’t use motor oil in an automatic. ATF is rather thin which has proven to lower temperatures. However, the latest specs for motor oil is getting rather thin as well. I don’t believe he was talking about sharing the oil like the HyDrive (or the original Austin/Morris MINI for that matter) The whole function of the HyDrive torque converter sharing the engine oil was to cool the oil. 11 quarts of oil can dissipate a lot of heat. The thing is a torque converter can generate an amazing amount very quickly. The Baker Grade on the way to Las Vegas is evidence of that with scorch marks every 100 feet from RVs burning to the ground from overheated transmissions. ATF will burst into flame at 425 degrees.