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  1. I'd say it is fuel related, today's fuel are different compared to the fuel quality that the car was designed for back then, which was heavier.Now they also add butane to make fuel cheaper I would think that it is percolation, where the gasoline boils in the carb and floods the engine. Does it smell like gasoline when you open the hood ? Also, try pulling the choke if you have one, if it gets worse then it is percolation for sure.
  2. Hi - I am desperately looking for a 1935-36 Olds differential Ring Gear and pinion set. Or the whole differential of course Thanks Rob
  3. Found my old thread and thought about updating this for general education purposes of everyone looking into this I had discussions with the techs at Optima back then and was told that it will never be possible to properly charge and balance two 6 volts betteries with one 12v alternator. So I have been running a 12v alternator with a 12v yellow optima and a 6 volts alternator with a 6 volts optima, placed flat on top of the 12v one. The ground is shared but the positive is sourced differently in teh system. This setup has been working flawlessly since 2007 to power my 6 volt car (negative ground) and the 12 volts fan & accessories.
  4. I use a High Power Impact wrench (Truck usage, not cars) on my 1946 @ 47 Cadillacs rear drums, never had any problems to remove it on the first try. The puller I use is a German-made Kukko puller, truck wheel type with 5 legs on a rotating axle which is easier on the studs than the cast type. The impact wrench was $400 and the puller $200. A car-type impact wrench will not be sufficient. See the photo: http://bigcadillac.com/jan07/puller2.jpg GM
  5. <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">You can run a split system with 2 6 volt batteries wired in series for the 12 volts and pull off individual battery for 6 volt stuff. </div></div> this won't work, batteries will un-blance and go flat quickly. the solution i have installed in my 1947 cadillac is to mount a second alternator for the 12volts and add a 12v battery wiht the + and - connected to the alternator. ground is on the 6 v for the car. I use a 12v optima and a 6 volts optima on top of it. i also use 3 12v electric cooling fans. Anything with a 6 motor could be damaged on 12v and a 12->6 voltage drop converter does not exist due to the high and unknow amperage draw of those motors, unlike small gauges. Maybe you could just change the motors to 12v motors ? GM
  6. advertising-ML-440508-ML- Moved to Commercial Advertisements...Peter J.
  7. thanks for all the answers ! I do use the nylon cages on my other 1948 buick and did not have any issues so far. Those seem to have a more precise, tighter fit than the old NOS type. The balls holded by the nylon cages seem to be kept at a better even distance from each other compared to the stamped cage design. However, as posted above It looks like overtightening it might cause more friction, and heat due to the additional friction might expand the whole assembly and cause more heat and eventually meltdown. So the conclusion would be that a bit looser is better than a bit tighter when it comes to choosing the right hole adjustement. Rob 46@bigcadillac.com
  8. Hi All, I just changed the inner and outer bearings and races on my 1947 cadillac front wheels, it now has the federal mogul,black molded bearing ball holder. Very tight tolerances and nice fit. Before there was the old "new departure" stamped ball holder type. The question is how much should I now tighten the nut holding the wheel. If I tighten it to the maximum, I cannot slide the cotter pin. To be able to slide the cotter pin I have to back-up the nut a bit but then the nut becomes quite loose such as it can be easily turned by hand. Not sure what the right balance of torque is best here...any opinions on this ? Thank you. Rob 46@bigcadillac.com
  9. i got that one : its a SPAL fan http://www.macsradiator.com/browseproducts/6-Volt-Electric-fan.html
  10. Ok thanks a lot for the very good suggestions here ! I'll check the timing & heat at the wheel hubs over the week-end. Oil cooler idea is great too I will see how I might add this. On my 47 caddy there is no Oil filter or outside oil lines. I'll keep the 6 volts system and just add another 12 volts anlternator, there is enough space to place a 12volts battery (optima yellow) and a 6v optima on top of it and have both systems.This shouod be done soon since I already made the braquets. The other advantage I can see with that 12/6 volt setup is that the 12 volt fans and 12 volt stereo will not draw the starting battery since those are on a separate circuit. Currently I am using about 75% water and 25% ethylene-glycol mix. I also use all new belts, cleaned the pulleys, and it did not slip. Blet tension is about 1/2" at the longest stretch. besides, a caddy flatheat has only a very short run between the engine pulley and the fan pulley. Water pump/alternator run on a sepearate pulley set. I did many tests at full throttle in my garage it worked fine with the mechanical fan. The issue is steam and boiling water coming out of the overflow tube using a 7lbs cap, after climbing steep hills and stopping/idling. The heat is being transfered fine from block to radiator. The issue is that too much heat remains in the radiator. yes airlfow is the issue because the car is cooling fine when it moves at 30mph or more. My new super-heavy duty copper-brass radiator is restraining airflow , thats an issue I clearly noticed that since I changed from the stock plate fins. It needs more air but also has much more potential to cool water using the same surface .Available surface is 19"x21" which is not that much to start with. I asked them to build that radiator with very high fin count and tight space between the tubes. cost me $500. I originally planned to go with an aluminium radiator but after speaking to a shop that has been building both aluminium and copper brass radiators for decades, I was told that copper-brass with a serpentine fin desing cools better at low airlfow and alumiium is slighlty better at high airlfow/high speed, race-type condition. Besides, even a major alumiumn radiator manufacturer such as Griffin is recommending using electric fans over mechanical ones, see: http://www.griffinrad.com/tips.php I still believe that an all-electric fan setup is a smart solution for city driving, since the slow RPM of those old/big engines might not be high enough to pull sufficient air at idle, compared to electrical fans. Above 30mph, no fans are needed anyway. So it kind of depends on the driving you do... The 4 fans I am using on the other car are the paddle type, not overly noisy and the sound is a low-pitched one. If the water goes above 195, they automotaically start spinning and cool the block very quickly so I don't have to worry about what speed I drive, rpms or outside air temperature.At highway speed the fans always stay off. I use a 180 degrees thermostat as well, so that I wont over-cool the engine. Rob
  11. The electric fans I am putting are 3 spal 10" puller fans in place of the mechanical fan. http://www.spalusa.com/fans/automated/tech_sheets/2057-2058.pdf 2 at the top and 1 at the bottom. those are rated 1070 cfm each and draw 10 or 12 Amps so we have a maximum total of over 30 amps on 12 V..a small motorcycle battery will not last very long. That same CFM would maybe draw 60 Amps on 6 volts if I were to use similar power 6 volt fans..a 6 volts alternator is maybe generating 50-60 amps. In case the fans are on for a long time that could be a bit risky. I also have a 500ci cadillac engine that had similer overhating issues, those engines generate a lot of heat to start with. I placed 4 of those spal fan on a shroud. I can now leave the car idling the whole day in mid-summer it will not go over 180F. fans are connected to a thermo-sensor inside the block, that switch them on automatically once temperature rises over 180. The radiator has been also recored. Its easy to notice how much more air is pulled compared to the mechanical fan. It will suck a thick towel and hold it against the grill, unlike a mechanical fan. Also, when I point my infra-red thermometer to the side of the block I can see how quickly the fans are cooling the block. Pull type fans are more efficient than pusher type, and you might need at least 2500 or 3000 cfm to have enough air to make a real difference.A pusher type in front of the radiator will also be a hindrance to the air flowing in. My block/pump should be fine since it cools ok when the car is moving, which points to an airflow issue. Maybe the presidiential cars might have been modifyied or improved for such purposes. Perhaps the 46-47 caddy flathead is generating more heat than other engine designs during that time. At idle it rates about 450 rpm, and the mechanical fan pulley ratio seems to be about 1:1.5, fan has 4 blades. I just dont see that small airlfow being sufficiant at critical times. Anyway, we will find out in the next 2 weeks how my solution is working... Thanks for all the answers. GM
  12. Ron, thanks for your input. Did not know about Scott`s fan, I will look into it. I use a 7 pounds cap. However, since water boils at about 212F and my other car never goes above 180F using the electric fans, the cap should not really matter if the cooling circuit is efficient enough... In terms of original design, I doubt that the car was designed to handle lenghty parade style driving speed in tropical heat or idling over an hour in mid-summer. I did found an empty spot on the driver bottom front side of the engine, under the fuel pump where I can place a second alternator. I already welded together a braquet that will bolt in place of the mechanical fan pulley holder. This will allow to use both 12 volts and 6 volts alternators at the same time, so that everyone will be happy. We get to keep the old tube radio, cute dim lights at the rear and other exciting 6 volts stuff, in addition to modern cooling & blasting CD stereos. I will post a few photos of the setup once I get this assembled this week-end or next, if this works... I just need to find a place to attach the 6 volt optima battery somewhere and that should be it.. GM
  13. MCHinson, thanks for your suggestions. I am using a newly re-cored radiator in this car. It is a 5 row copper-brass with a very high fin count and tight space between the tubes (about 7/16"). It has the potential to cool the water much better than the stock, plate fins radiator. I used the same desing in my other car and it works great wiht electric fans. However, I found out that this design does restrict airlfow, it requires a stronger airflow if not water will boil quicker than using the stock radiator. I have replaced all 4 hoses with new ones, a new 180 thermostat and I also tried withtout the thermostat. The block is heating the water fine, there are no heat exchange issue between the block and water and the water pump seems to be working ok since it cools the block when there is enough aiflow, such as driving around at 20mph or more. Airflow seems to be the issue. I also have a 1948 Buick and it never overheats even in summer when idling and traffic, and it is completely stock without a shroud. Those caddy engines are running hot. Maybe ignition timing is not set well, I will try to investigate this as well but the engine is running fine. GM
  14. The reason is that I want to add electric cooling fans to replace the mechanical fan. Mechanical fan does not pull enough air to cool the water/coolant mix in the radiator at critical times, such as after steep hills or very slow traffic in very hot summer. It will boil over. Maybe it worked fine 60 years ago with the traffic at that time but for where I live its just not working. I did some tests with using after-market mechanical "heavy duty" flex blade fans, using a shroud etc.. which gives a better result than the origianl 4 blades fan, but still this is a far cry from what electric fans with a shroud can achieve. The slow rotation of the engine is just not sufficient. I did place electric fans on the engine side of another old car and this works great and pulls a lot of air. Solved all the issues. Coolant never goes above 180 degrees. It uses 4 fans for a total of over 4000 CFM. I also have the 14" Spal 6 volt electric fan but this is not powerfull enough.You would need 12 volts for an all-electric fan setup. Otherwise 6 volts are fine for starting, lights brightness and driving my car and I use a 6 volts Alternator in place of the old generator.I'd rather keep everything stock if I didnt have those problems.
  15. Ok I see thanks for the reply. Here is another idea then: connecting the 6v starter to the 12 v battery using a smaller diamater cable to introduce some resistance on purpose. cable may overheat but thats a small risk compared to burning things inside the starter. GM
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