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About edinmass

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  • Location
    Springfield, Massachuetts
  • Interests
    Pierce Arrow motor cars. Brass cars. Pre WWII only.
  • Occupation
    Restoration and matainance of CCCA cars.

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  1. Tank the tank off, plug all the holes except one, and fill the tank with a few pounds of dry ice. Let stand for two hours, keeping the open hole on the “top”, dry ice is pure co2, and will constantly replace itself while you are soldering the tank. It’s the only safe way short of a continuous flow of co2 or argon while doing the job. It’s cheap and easy..........👍
  2. I thought it was time to make this post, as Steve, Tim, and Tony are too modest to do it. Incredible is the only correct description of their accomplishment. It’s beyond any other words that I can come up with. Decades of searching, labor, scholarship, and perseverance. Congratulations gentlemen, you deserve the Nobel Prize of vehicle restoration. Thank you for many hours of entertainment. You bring much joy and happiness to many people following your exploits!
  3. Steve, spoke to an old time engine shop and Babbitt guy today, we spoke of your problem, and he commented your ring gap should be .020 , I think he is about right. I too have finished vehicles that don’t get driven much. A made a new rule, If I don’t drive it twice a year, I sell it. More than 75 percent of my stuff went down the road......which was fine. Currently I have 17 regularly exercised pre war exotic cars kept in top running condition. It’s just about a full time job. After two years, today I managed to clean and wash my every day Ford Focus. It looks much better! Ed
  4. Steve, I think you are on the right track. I would replace ALL the rings. I would change the oil before start up. I would also change the oil again after an hours running in. I would use a straight ten weight for the first two changes, and then go to a straight thirty after that. Once the lorry has a few hundred miles on it I would switch over to a 100 percent synthetic. If you choose not to run anti freeze, use distilled water with cutting oil in it. Prevents rust, lubricates the water pump, and if it leaks or overheats it cleans up with a garden hose. I take it there is no chance for a freeze where you live........if there is a chance then obviously anti freeze is required. Looking forward to seeing her back on the road........and looking forward to the next updat! Ed PS- a magnetic drain plug would also be a good idea.......I would devise a way to install a few magnets in the oil pan as well, even if you can’t get to them often, they can be a big help.
  5. I was more intrested in a before and after number after expanding the ring gaps and opening up the bore. It would have read low on the two holes with the stuck rings and let them know before disassembly how many cylinders had problems. Compression tests and leak down tests can be helpful in understanding ring seal. Also it could identify unknown valve sealing issues. It’s an easy test that’s done in a few minutes. On the Rolls I can shut down the car with a charge in the cylinder and come back an hour later, swing the distributor and get it to fire thus giving what we call a “free start” without touching the starter. Fun to do at shows and a great indication of a good engine. All just for fun. That one hole without soot on top of the piston should be investigated, it may mean a manifold vacuum leak or a poorly sealing exhaust valve, or ignition problem on that one. A cylinder balance power Check while running would help identify any loss of power if there was any. It may also be no problem.........worth checking out. Steve asked how I found this thread and I didn’t answer. Back in the early seventies a family member had a WW I Renault tank that I use to play on. They had it out in the front yard as a lawn ornament. As I’m sure they are quite rare, I was attempting to locate it for possible purchase. Ended up chasing down a Stewart and a Sherman. I built my garage attached to my house to handle the Sherman, but never managed to land one that was in my condition and price range. Still want to add a WW II tracked toy to the collection. Most likely something lighter as I dont want to own a tractor trailer to go to the shows.
  6. Don’t forget to open up the ring gap. .008 will probably be ok, but rather than take a chance to do it twice I would go just a bit bigger. Did you ever take a compression test before disassembly?
  7. Well, it’s not too difficult to fix. Replace ALL of the rings, hone ALL the cylinders, .009 minimum. On such a low use vehicle, and low speed engine I think I would go to .010 or .011 for ease and safety. Remember you have NOT run that engine hard yet, just for a short time at idle or above, under maximum load for longer than thirty minutes I think you need more clearance. Just .003 isn’t enough in my opinion. I spent the last week at Lake Como for the Concours D’ Elegance with our 7.8 Litre Rolls Phantom II, with a 4.25 inch bore six cylinder engine. The motor was built “tight” and we had the cast iron pistons at .010, while it runs and starts fine, with everything new including the radiator and all internal parts and bearings, it’s still running just a bit warm if we idle it for twenty minutes at a standstill in any temp over 20c. I’m sure it will be fine in a few hundred more miles. I would change the oil on the Thorny two or three times, right away after you reassemble it. I would recommend a five weight oil for the first two changes, then I would go to a straight 30 or 40. After five hundred miles of running I would then go to 100 percent synthetic. Photo enclosed of the 7.8 Litre P II with me in front of it yesterday at Como. You gentlemen do great work, and I look forward to visiting you with a car to take you for a ride in the future! My best, Ed
  8. Steve, The earliest car we have serviced is 1897, and the newest is a current Top Fuel (nitromethane) dragster, so we have been all over the board when it comes to pistons, piston troubles, and attempted solutions. Most of what we have is 3.5 inch bore plus or minus, but we have done six inch down to just over two inch. My first paying job as a teenager was running a boreing bar machine after school and weekends. It’s best to just cover your current situation here to keep things short, and I will address what I think I would do. I’m not sure it will be very helpful, but I will try. 99 percent of the time we use custom pistons made for a application that the piston manufactures make all the decisions. We learned over time when we got in the middle of the engineering and decision making we ended up with problems! You have many issues in play on your Thorny, new sleeves, modern fuel, possible jetting issues, home made pistons, unknown alloy, etc. In the current situation I would do a tear down of the engine before I made any decisions. I expect that I would probably increase ring gap, and depending on what you find, I would tend to leave the pistons alone and hone the cylinders. I’m quite sure your problem won’t run in and solve itself. I understand and respect the reason you made you own pistons.........it’s an impressive accomplishment and very few people I know have done it. The question now is, keep what you have and attempt to fix it..........and you may or may not be successful on the first try. I understand the challenge of getting it right after all you have done on the vehicle. I would tend to order modern pistons, as you know the bore and stroke, and have an old piston sample, it would be easy to just order a set of new modern pistons, drop them in and forget it. BUT after following along with you for years on both of you trucks, I’m sure you much rather deal with the problem and finish the job you started. Cam ground pistons were the norm for years, but if one doesn’t have access to a machine I think you can still move forward. As the engine turns quite slow, I think you can solve most of your problems by opening up the ring gap and piston clearance. I would go to .009 or .010 on the piston clearance. I would set the ring gap at .016 on the compression rings. You can turn them and taper them as mentioned in you post similar to what you friend mentioned on the Ford T, and I don’t think think you will risk anything. With such a low compression ratio, leak down and blow by won’t be an issue. Holding things tight on this particular job isn’t too your advantage. If you build it loose, the only downside will be piston slap when cold. Run the fuel mixture rich, and add as much timing as you can. Lean mixtures make the motor run hot, and can burn valves, melt pistons, and crack rings. Does the thorny have a thermostat? Most engines ran at 140 before the 1920’s, and went to 160 by the mid 1930’s. Also, with today’s modern fuel you want to run a hotter spark plug if available. We use a five gas exhaust analyzer when we set up the carb and ignition. I’m looking forward to see the pistons and cylinders when you take it down. Also, have you done a compression check on the engine yet? It’s a worthwhile exercise to see what they are wet and dry across the board. I’m sure others here will chime in. I look forward to their experiences and responses. Ed.
  9. I looked over the thread and couldn’t find what you used for piston clearance. A minimum for this application should be .007 and a max of .010 . I wonder if the liners are causing a heat transfer problem with the block? Or possibly the home made pistons and material could also be an additional unknown as far as expansion goes. After many years in the hobby we have learned to run an engine on a stand or dyno for several hours before installing it. I know you gentlemen are pressed for room and are working on a time as available schedual, and it would not have been practicle for you to run it out of the truck. With the amount of service the truck will ever see, and modern oils having made great strides from when the truck was new, I would set up the piston as loose as you dare. You may get some cold start up slap, but once warm it should run quiet. On our cars with a six inch bore we run .012 and they have worked out fine. Once the motor is properly broken in, you can switch over to 100 percent synthetic motor oil. That way there will never be a scoring issue or oil failure with major damage. Depending on cost and time, maybe a modern set of pistons with modern ring packages would be worth considering. You could have them made so you only need to do a light hone and reassemble. The good news is the top end comes apart relatively easily. You have done a great job on this truck. I wouldn’t call it a restoration, I would call it a resurrection! Job well done! The dedication your family has saving our history is truly inspiring.
  10. If you are going to consider easier starting, here in the States the early big car guys have worked out a very slick set up. They run a 12 volt starter Generator combination from a small desiel lawn mower. They use a small gel cell battery for power/storage, and a flat belt around the flywheel. The whole thing is very compact, and can usually use existing frame holes or clamp on brackets. It requires almost no wires except the starting button that can be well hidden. The unit is whisper quiet, and works quite reliable. Price is very reasonable and installation with proper planning is usually a breeze, and can be removed for judging easily when required. I have seen this set up spin a twelve liter engine. Many of us here across the pond enjoy watching your projects, and I often hear people commenting about you gentlemen at car shows. Truly a global initiative! Last summer for the second year in a row we brought a car over to tour the Cotswolds, a wonderful place to drive a car. The roads can be quite narrow, and driving on the opposite side in a 85 year old large car can be quite a challenge. I hope to see you at Brighton in the next year or two, as we are hoping to get a pre 1904 machine to make the run. The photo below is on the road to Broadway. Thank you for the many hours of entertainment you provide all of us every year! Cheers! Ed.
  11. Hi, unless I missed a post you haven't made an engine ID have you? I am quite sure I know the foundry mark showen in the post of the S in the triangle. I have seen it on lots of engines here in the states. I don't want to post an incorrect answer, but if you have not locked down the ID I will post my information. Ed.
  12. Piston manufactures in the USA 1 Egge 2 Ross 3 Aries I have had poor luck with the first company. The other two are good, and now I usually use number 2. They all have web sites, just google their names and the word piston. They also provide rings and pins. We always order modern ring packages as they burn less oil and crank over easier. Ed
  13. Gentlemen, I have thoroughly enjoyed you restoration saga of both the Dennis and Thornycroft. Very impressive work and I can't say enough to thank you for your wonderful generosity for sharing it with all of us. Any new information on the pistons? Are you planning to make them yourself? They are very easy to order here in the US to any specification you may want. When we order new pistons, we order them with a slightly oversize small end pin, then ream the small end to a perfect fit. Saves time and money by not installing new bushings in the rods. Ed M. Boston, Massachusetts
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