Loren

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.

When you look at a HyDrive engine there is a relief valve on the oil pump in addition to the one in the block. It makes you wonder why they put that there. Could it be that the Torque Converter generated its own pressure? Aside from people forgetting to drain the Torque Converter every engine oil change, I wonder what the engine longevity is vs a standard shift. HyDrive has always fascinated me being the ultimate FluidDrive. If it added to the life of the engine that would be another reason to find one. (one of my modern cars needs to have a transmission oil change every 70,000 miles. The car lets you know its time when the transmission slips going up a hill in high gear. After I had the dealer do the service -once, I only got 55,000 miles and it was slipping again. I talk to a number of friends in the trade and they said, "Nobody drains the Torque Converter". Needless to say I now do that service myself)

James brings up a good point about anti-freeze. The main reason the "Green Police" don't want it on the ground or down the drains is that it is poison. Pets (and animals) are drawn to it as it is sweet to the taste. A pan sitting on the garage floor is a very real danger to pets. There are however safer alternatives. Anti-freeze for solar hot water systems that is labeled Non Toxic might work in engines. I've never tried it but I know with a little shopping you can find non toxic automotive anti-freeze. You will pay a high price for it however. An old buddy of mine told me how they used to keep Model T Fords from freezing up in the Northern Wisconsin Lumber Camps. They took thin lubricating oil and filled the radiator with that. In the spring after the last frost they replaced the hoses and the oil with water. We've all seen radiators with milk chocolate colored water circulating in them. I attended an Allen Test School and they were explaining how electrolysis occurred, motion, dissimilar metals and water. They claimed a radiator could generate a measurable electrical current and that current was eating away at the iron (or aluminum) of your engine. At the time I drove a well used 1958 F100 with a 223 I block 6. To test their lesson I clipped my volt meter ground clamp to where the radiator cap mounted and held the positive in the center of the water with the engine running. The old Ford put out 12 volts! Needless to say I quickly added radiator maintenance to my 'to do list' on the pickup!

160 is an appropriate thermostat for a 49. 180 should really be used in a pressurized cooling system. Everybody knows water boils at 212 at sea level without any more than atmospheric pressure. No matter how much heat you put to a pan of water it will stay at 212, until you run out of water. The water evaporating cools the pan and keeps the water at 212. Use 50/50 coolant and the boiling point goes higher. Add a pressure cap and for each pound of pressure the boiling point goes up 2 degrees. So on the cars I used to work on the red area of the gauge was where the coolant boiled, 265 degrees! According to the factory 264 was okay. There’s a few things one needs to know about cooling systems: When you shut down an engine it gets hotter. The coolant is no longer circulating. When you’ve boiled off coolant the temp gauge will read lower because it is no longer covered with coolant which it needs to read correctly. Air in a cooling system will prevent it from working correctly. Robinaire (among others) makes a device which places your cooling system under vacuum, then if the vacuum holds you can open a valve and fill the system from a tube in a bucket. This gets all the air out and is useful for vehicles with complex hard to bleed cooling systems. Some times a mechanic will drill a small hole in a thermostat in order to induce a flow past the wax bulb. I used to do this when I noticed that engines would get hot well before the thermostat opened. The coolant under the thermostat was stagnant and didn’t get hot when the car sat idling. I’ve seen temp gauges peg before the thermostat opened. Just a small hole stopped that problem. Anti-freeze is made from the same chemicals as brake fluid and smells exactly the same when burned in the engine. A white cloud following you in addition to the smell is a good indication of a blown head gasket or a power brake master cylinder leaking. I once had both happen to the same car.

Remember you’re getting “a pig in a poke” You have no idea if they are any good. To me they looked like they’ve been under water. The seller wants $1,000 each, not sure that will happen. The last one I bought on ebay, I paid $475 and it turned out to be in good shape (and it looked better than those). The safe thing would be to offer $1,500 for all three and hope you can get one good one, or make one good one out of the three.

I started to work up two chokes using the second boss for a second sessons automatic choke on the exhaust manifold, after noticing that Plymouth had moved them in the past. A friend told me it was unnecessary as you only needed one to start the car. So….there’s another vote for a single choke. Sure is a lot simpler.

Having spent several decades in manufacturing I can tell you drilling holes in metal isn’t as simple as you might think. Engineers talk about the diameter vs depth ratio and the types of drills required to achieve deep holes. The problem is getting the chips out of the hole while drilling. Deep hole drills have one cutting surface (your typical jobber drill of course has two) made of carbide brazed to a tube that looks like a quarter pie sliced cut out of it when viewed on end. The tube is connected to a high pressure pump which forces coolant out of a hole in the carbide. The coolant literally blows the chips out of the hole. ( what I am trying to describe is called a “gun drill” if you’d like to google it) What the various diameters are may be a function of how they drilled the holes. It must be remembered that Plymouth and Dodge made their own engines in their own factories and thus could have used very different methodologies. I have only dealt with Plymouths and never noticed the different diameters. I am thinking it can’t make much difference. It could be that it was done as a two step process with two different drills. The larger diameter for clearance of the second drill on a rapid approach. Even with a gun drill there are limits to how much torque can be applied to the drill with chips coming out of the hole. Finishing with a smaller drill makes sense in that case. The hole that I am impressed with is the one running the length of the block. I am not sure boring out the holes would be of much value. The more volume the pump has to fill on cold start up is more time the bearings are not getting pressure.

If you take a look at the cam bearings you will see two sets of holes. One set is smaller than the other set. I will let you ponder that a moment. The oil pump is on one side of the block and the oil galley is on the other, it takes a cross over tube to connect them. The oil passage doubles back with thru holes to the other side. Now look at the crankshaft. The front main feds oil to cylinder #1 and the rear main feds cylinder #6 all the other mains feed two cylinders each. If you were to guess which rod bearings might suffer from oil starvation, you’d say #2,3,4 or 5. But theres more, because the rods are fed by one hole drilled in the crank, there is a timing issue as to when they get a full shot of oil. 40 lbs of oil pressure does a good job of lubrication and the pump has enough volume, especially when you consider what Chevrolet gave their engines. Pressure to the mains, cast iron pistons and dip fed rods! Many after market parts makers have noticed on OHV V8s that the oil goes to areas where it really isn’t needed. Smokey Yunick made oil pans, timing covers, valley covers and rocker covers out of clear plastic so he could study where the oil was going. He started putting restricters in the oil lines to the cam bearings and lifters as a means of directing more oil to the mains & rods. In our case that is why the cam bearings have two sets of holes. Standard practice is to use the small holes on number 2 and 3 cam bearing. The front bearing feeds the timing chain and one rod bearing. There is no rear bearing as the cam runs directly in the bock and feds only one rod bearing. I talked to one old boy who said they used to cut a short piece of lamp wick and insert it in oil galley and push it over to the cam bearings as a used car lot fix for worn bearings. I don’t think I’d recommend that but you get the idea.

You are not mistaken at all. In fact you are right on the money. The 49 has 4 bolts holding the upper A-arm pin while a 55 has only two and very likely is wider and the A-arms longer (if not mounted in a slightly different spot). That is the fly in the ointment. Right about where you would want to drill the hole for the upper shock mount is almost exactly where the pivot pin passes over the spring seat. It could be done if you are willing to saw the pivot pin near the bolt bosses and weld on a flat bar with a hole in it for the shock mount. Of course that means a disassembly of the front suspension. Sounds like a whole lot of work to me. It could be done and it really is an elegant solution if you need to do that much renovation to your suspension. In my case the car has only 38,000 miles and doesn't wander. My front shocks were worn and so I've replaced them with new stock ones. In the mean time I think I will be on the hunt for someone who has replaced the front frame clip. If I have to do that much work, I want to clean and paint every piece. The ideal way to do it would be to get a front clip that you can turn over and find the perfect spot for the upper mount, drill it, modify the upper pin with the flat bar and transfer the hole to the bar. Then when you trade pieces on your car you can use the pin as a drill jig. The lower A-arm might benefit from welding spots to bolt the plate to the bottom for the lower shock mount. Since I have lots of other high value projects I think I will put this one on the back burner till I get a front clip.

After considerable effort I got the coupe into its new garage/shop. The neighbors told me they hadn’t seen the door open in 5 years. I now know why. I will be rebuilding the door. Once inside I pulled the front wheels and did some brain storming. First off I rejected the Ford F1 mounts. Plymouth uses a boxed frame and the pick up used a channel frame. Not surprising as pick ups were cheaper than cars back in those days. Plymouth even though a low priced car was built to a higher standard than pick up trucks. Boxed frames being inherently stronger can also be lighter or at least made from lighter material and that is the case here. For several reasons I rejected bolting the F1 mounts to the frame. I looked at the possibility of using fabricated mounts as well. I didn’t like that idea either. Welding to a frame is done all the time I know and folks will question my sanity when I mention my objections to doing it. If you weld across the frame member, if it is going to crack, that’s where it will crack. The rule has always been if you must weld, it should lengthwise or better yet use rivets. Rivets or bolts can use doubler plates which is difficult with welding most of the time. So I am not keen on relocating the upper mount….still. I did more research on the 55-56 shocks. You can order them front all the regular suppliers but….since there is only one outfit making them they are out of line price wise. I don’t want to experiment with pricey parts I have no use for if it doesn’t work out. That said, the concept of mounting a second shock inside the spring (like the 55-56 Plymouth) sounds appealing as you only have to drill three holes. I found two shocks which might work but I am going to do more measuring. The first came on the 1975-80 AMC Pacer. Don’t laugh. The second one will require a plate to mount it on the bottom of the lower arm. This shock has been fitted to nearly all the GM brands at one time or another, Fords, Studebakers and interestingly the 1961-72 Volvo P1800, which means you have all sorts of great choices in shock brands such as Koni, Bilstein, KYB etc. So that is the latest in my thought process. When I get the dog gone door rebuilt, I will be able to do a test drive.

One key in the deciding if it is a Continental or a Chrysler is the location of the distributer. Chrysler on the side Continental on the top of the head. This way in one quick glance you can tell.

You scored my friend! On eBay there is a guy with lots of throttle switches which will work (non-stock but the same type) for $6.25 (I bought 10) They were made for the government and had International Truck P/Ns. For the relay you can use a Bosch Square type that go for very little ($5.00 or less). The 12 volt version is very common as the alarm and stereo guys use tons of them. I found a German made 6 volt version on Amazon.com for I think $8.00. PM me for the pin numbers to the stock wiring. As for the Lock Out Cable I would go to my speedo guy and have one made for less than the ones that say "Overdrive" on the handle or www.vanpeltsales.com for a reproduction. Van Pelt sells the solenoid and the governor if you can't find a better price on eBay. Also, take the speedo gear out of your old transmission and put it in your new Overdrive, they fit. Then your speedo will read correctly. If you have a short wheelbase Plymouth you will have to shorten the drive shaft and make an extension rod for your e-brake (absolutely necessary to have a working e-brake on an Overdrive car). However, if your old gearbox is the long version (same length as the Overdrive) then don't worry it just bolts in. You will really appreciate the Overdrive in a Plymouth!

This is exactly why I trust the factories engineers over my version of what passes for engineering. The notion of using the 55-56 design along with the original location seemed to cover the engineering issue but not the supply issue. The thread from 2015 never got to the point of identifying the right shock. It seems the fellow closest to a solution couldn't say exactly what he was using. "Original" meant what was on his car when he got it but not necessarily what was OEM stock. So...we don't have an answer as yet. I have a new set of OEM spec shocks and I have ordered the short F1 mount from Speedway. The only way to prevent bottoming is to remove the spring from one side and measure the wheel travel at the mounting point of the shock. I might even drill an old shock to release the oil and any resistance. The idea being is to avoid any binding or tweaking of the shock. Hopefully I can generate enough data to pick the right shock.

Easy. The between the A-arm set up was a clever Chrysler innovation to improve the longevity of the shocks, which it did but...all choices in engineering are compromises. When the speed limits were 45-55 mph it made a lot of sense. At 65-70 mph not so much. We have to remember what we think is an "improvement" is just a compromise with different goals. The 1955-56 compromise kept some of the short travel long life goal but added better road holding. Now we have a different set of goals, better handling of course with future access to replacement parts at reasonable prices. From my research there are limited choices for stock shocks, limited choices for the 1955-56 design, so I have to make a decision (or a compromise if you will). Right at this moment I am leaning toward the F1 mount. What would cinch it would be to know the right shock to use. Any suggestions?

I am loathe to make changes to Chrysler's designs. I figure the engineers know a lot more than I do (It doesn't take much imagination to reach that conclusion. lol) When I remembered the 55's characteristics and it seemed like a great idea to use that update, but...those are not real common shocks either being two years only. The stock set up was not made for "spirited" driving to be sure. It was made for long service and wear. One of the great charms of the Plymouth. I am softening to the idea of the 1948-52 Ford F1 upper mount (www.speedwaymotors.com has reproductions in two lengths) because of the availability of a better selection of shocks. The modification is something that could have been done during the time period that the car was made so there is that. While the shock travel is more than the 55-56 design (and much more the 49-54) I would expect similar or better characteristics. Now to find the right shock.