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Posts posted by Ltc4748

  1. An easy way to see if there is a light socket that is not grounded is to connect a test light to the grounded battery terminal. Turn the lights on needed to make the feedback occur. Now touch the test light to the base of the bulb that quits working when you turn both the lights on, does it light the test light? A bad ground connection will make the test light glow steady or flash if the turn signal is flashing. The test light proves the bulb is not grounded by lighting the test light. Next touch the test light to the metal socket the bulb goes in, does it light there? If test light does not light on the metal socket the poor ground is between the bulb and the socket. If the test light does light on the metal socket then continue to check the ground path by touching the test light to what the socket mounts into and look for the results. You can determine exactly where the poor ground is this way so you can repair the issue. 


    Also the same test light can be used to check for a parasitic draw/battery drain. On cars without any computers just unhook the ground cable from the battery terminal and connect the test light between the terminal and the cable. The test light will not light if there is NO battery drain. To see if your test light has a good connection and is connected correctly for this test open the car door or turn the key on and the test light should light showing there is a path for current to flow. If the test light does not light the test light is not working or has a poor connection.         For reference less than a .02 amp parasitic load on a new vehicle will not even make the bulb filament glow a dim red. Computerized cars are able to draw up to .02 amps and are fine unless they set for extremely long times such as months at a time. Then the battery will not start the car due to the discharged state If you want to use a test light on a car with a computer you must disconnect the cable , connect the test light between the Battery terminal and the cable, then with the test light connected it will probably be lit, while keeping the test light connected touch the cable end to the terminal the test light should go out, then take the cable away from the terminal keeping the test light connected. If the test light stays out the battery does not have a drain, if it glows dimly you must perform the test with an ammeter to verify it is under .02 amps or the manufacturers specifications.


    Best of luck to you, Larry 



    • Like 1
  2. With all the plugs in the engine take another plug and connect it to the plug wire leaving the extra plug external and crank the engine. Does it spark? If not the mag does not make enough voltage with the slower engine cranking speed to fire the plug. Check the cranking speed with the plugs out and with the plugs in. The engine should turn over at least 125 to 150 RPM's at cranking for the unit to start well. If the cranking speed with no compression is 100 and with the plugs in the compression drops the speed to 70 I would look at why the RPM's are so low and see if it can be improved. The other cause would be if the cranking speed is normal and there is no spark from the Mag then it is not producing enough voltage to jump the gap. Connect a 12 volt test lamp to the plug wire on one end and ground the other end of the test light.With the plugs in the cylinder, crank the engine. see if it makes enough voltage to make the test light flash. If so the mag cannot produce enough voltage to fire the plug at that cranking speed. If cranking speed is normal the mag is weak. If cranking speed is low see why and get it to where it needs to be.

  3. If I remember correctly the vacuum advance on these cars was disconnected when you set the static timing at idle speed. The vacuum supply is manifold vacuum so when you reconnect the vacuum line the distributor advances the timing  for the full vacuum advance degrees. When driving the vehicle the vacuum drops as load increases and retards the timing from the full vacuum advance. Mopar must have found that the engines started better hot with timing retarded or another similar benefit came from the retarded base timing.


  4. CoolChem makes a glue that works great for all kinds of repairs for a reasonable cost. I use it on multiple items and have great results. I repair car /truck plastic dashes Toy trains and other things as needed. Be carful when using on plastic , it uses an acetone accelerator to instantly dry the glue so some plastics do not like it. Once the glue dries you can build a strength layer with the material.

    Best of luck.


  5. I worked on farm equipment for my last real service job from 2013 thru 2016. The condensers we get now are made in area's that there are no or very poor quality control checks. I have seen several condensers during that time which work for the half but will not generate the field collapse and fire the plug . These were on older equipment which had complete tune ups that went to the field and didn't work more than a hand full or two of times and then they would begin to start hard, no start or run for a short time and shut off then not restart. I would definitely try another condenser if it were me. I know a great starting engine will fire a plug with 3/16" gap when external of a cylinder. If you have a plug tester available that adds simulated compression pressure (using air pressure) to the end of the exposed plug while firing voltage to it you will see the more pressure the higher kv the plug needs to fire correctly. Blue spark is great but if it can only jump .03" when external of a cylinder with no compression pressures when you add the compression and fuel mix it will fall on its face. The other thing I have noticed is the spark will arc to ground when compression is on the plug if external arcing is the path of least resistance. I do not think this is your issue because the timing light does not trigger. You can check for this by trying to start in a dark area with no lighting. 

    I do not know it all but I will try to help.

    Best wishes on your repair 

    • Like 1
  6. With the plugs in the engine connect one plug outside like you have been testing it to confirm no spark, If there is spark present I would open the gap of an old spark plug to 3/16" and see if the spark will jump that gap. If it does not jump 3/16" it probably will not fire a cylinder under compression. if it doesn't jump 3/16" double check the points to see if they are shiny clean the whole face of each point. If they look good I would replace the condenser if it has one and retest.

    • Like 1
  7. A reply to Matt Harwood. The Vintage Motor Touring Society will gather again starting this spring and in a group of up to 15 or so prewar vehicles we will cruise to a collection, a museum, a hobby or historical society or whatever the tour master chooses then stop for lunch. After lunch we all head home until the next months run. It doesn't get any better than driving an antique car. We avoid highways when possible but will run them when needed. We do the run on a weekday most months to avoid heavy traffic.

  8. I also have used a red or black magic marker, painted both the valve and seat, put the valve in and turned it back and forth about a quarter turn with light pressure. Then removed the valve and looked at the shiny area of contact. Be carful with the lapping compound, any not thoroughly cleaned out will cause excessive wear if it gets into the wrong area.

    • Like 1
  9. You state low compression but the rings were intact, the only damage if I understand correctly is the ring land on the piston was broken on this piston. You also have 3 more with no-compression. If the compression was 0 psi on the cylinder that had the broken ring land I would check the valves and seats on that cylinder closely by putting a ring of light oil or diesel around the valves margin when they are fully closed and watch to see if it weeps through the valve and seat. Typically a piston that does not have any broken rings and no scoring will be low compression which still does not run correctly. If the other 3 cylinders pistons show the same damage I would suspect continous detonation in the cylinders from timing being advanced too far or someone was using ether to start/run the engine. if all 4 piston ring lands are broken I would replace all the pistons. If you reuse the pistons be sure to check ring side gap and end gap, both are equally important. Excessive ring side gap can also break the ring lands.

  10. You can turn the cable between your fingers and watch which way makes the needle move upward. Then take an old speedometer gear if you have one and chuck it in a drill to run it faster or put the cable in the chuck and tighten the check only enough to hold the cable.

    • Like 1
  11. Hello Dennis, yes that is correct for the engine if the timing marks line up with #1 cylinder on TDC and the valves on #1 are both open slightly, known as valve overlap, then the distributor would be installed with the rotor pointing to the #4 plug wire

  12. use a timing light and check the mechanical advance and the vacuum advance separately. The Timing should be set with the vacuum disconnected at the proper idle speed. then hook the vacuum back to the distributor. If the vacuum line comes from manifold vacuum the timing light will show the mark (Timing marks on crankshaft) advanced when the vacuum is connected. If the vacuum comes from a ported location on the carburetor (vacuum line connected above the throttle plate) it will only get advance from vacuum when the throttle is opened. You can substitute manifold vacuum temporarily to check for proper advance with the timing light and if OK put the correct ported vacuum line back in place for operation. To check the centrifugal advance leave the vacuum disconnected and with the timing light raise the engine speed while watching the timing marks. As the speed increases you should see a timing increase if the weight system is working.


    One of the biggest mistakes people make is to put points into a distributor and set the ignition timing with a timing light without disconnecting the vacuum to the advance diaphragm at the distributor. This has the timing set on the retarded side which will lower power and fuel mileage.


    I hope this will help you.

    • Like 2
    • Thanks 1
  13. The timing gear marks can be different set points for different manufacturers. Most Manufacturers of 4 cylinder engines haver it designed that when the gear marks line up the valves on cylinder #1 are on overlap at TDC. so at this point if you are putting the distributor in on a 4 cylinder engine you would set the rotor to point to number 4 since this cylinder is on the TDC of the compression / power stroke. Other manufacturers made the engine marks line up when the valves are on overlap on #4 cylinder ( on a 4 cylinder engine) so on this type the rotor on the distributor would be set to point to #1 cylinder when installing it since 1 is on the compression / power stroke.

  14. You can test the fluid by exhaling over the opening of the tester while squeezing and releasing the rubber bulb several times. This way you will see the yellow color the fluid will turn. Then repeat squeezing the bulb several times in fresh air and the fluid will return to blue. 

  15. I have seen the sealing area's around the spark plug hole pit from rust. I had a machinist make a cutter that I turn by hand to cut the surface smooth and use new copper gaskets from a hydraulic shop. I test the sealing with a spray bottle of soapy water while the engine is running to see if it still is leaking. I have good luck getting them to seal. On one hole someone popped the starting thread and it left a recess. That one I put a thread insert in so it replaced the sealing area. 

  16. To check dash unit disconnect wire on sending unit and keep it away from ground,  key on engine off the gauge needle should go to one end of the scale either full or empty. Next with the key still on ground the wire that went to the sending unit, gauge needle should go to the the opposite end of the scale. if the gauge responds correctly the sending unit or tank ground is bad. If gauge does not respond correctly it is either a bad voltage supply, bad wiring or a bad gauge itself.

  17. It is actually a guessing game unless you install a pressure gauge and see what the cold and hot operating pressures are. If the pressures are below around 5 psi hot idle the light will come on. you can check the sender by measuring resistance with 10 psi pressure applied by an air regulator and gauge readout and then slowly turn the regulator down in pressure until the light goes on. If the pressure is low check the relief valve, if OK then remove the oil pump and pressurize the oil galley and see where the larger leaks are or check each main and rod bearing. Also pull the cover off the oil pump and check the gears and pockets for scoring. Gears should only have about .001" of clearance. Also when pressurizing the oil galley watch for oil leakage in the timing cover  or another area. I have seen many "rebuilds" where someone forgot to plug or correctly reseal an oil galley.

    Best of luck to you

  18. The easiest way to check for a battery drain is to take the ground terminal off the battery and connect a test light between the battery post and the terminal. The light should not even glow a barely visible dim red color. To check if you have it connected correctly and that the test light is good open the door or turn something on, the set light will glow brightly. This can even be used on new cars with computers but there are other steps you must follow. If the light is glowing and everything is off disconnect one thing at a time until the bulb goes out.

    Best of luck


  19. If the brake pedal is hard like the brake is when the engine is not running check for vacuum at the booster by removing the vacuum hose at the booster while the engine is running at idle. Engine should stall immediately due to the large vacuum leak, check that the hose is not soft and sucking shut while the engine is running. If vacuum is not present or only a slight leak look if there is a one way check valve in the vacuum line (some look like an inline filter) , if there is none in the line and the engine stalls when the line is removed check the connector at the booster, it may have a built in check valve. I have seen these go bad and you may get one power assist but if you let off the brake and press it again the pedal is rock hard.

  20. Most auto parts stores have a glass center fuel filter that uses a fine screen to catch debris. The nice thing is you can visibly see if it is dirty and it easily comes apart to clean and put back together. I am using them before the Vacuum tanks and at the lowest point in the line with easy access to inspect. It has not interfered with the operation of any of the vacuum tanks yet for me. They cost about $10 and are 1/8" female pipe threads. They come with plastic fittings but I install brass ones. The filter is maybe .75" diameter and 2" long


  21. Most auto parts stores have a glass center fuel filter that uses a fine screen to catch debris. The nice thing is you can visibly see if it is dirty and it easily comes apart to clean and put back together. I am using them before the Vacuum tanks and at the lowest point in the line with easy access to inspect. It has not interfered with the operation of any of the vacuum tanks yet for me. They cost about $10 and are 1/8" female pipe threads. They come with plastic fittings but I install brass ones. The filter is maybe .75" diameter and 2" long




  22. While in college during the 70's I remember the course on the braking system. We had theory and literature that spoke about the brakes in detail.  When the lining material went from the woven type to the asbestos base and each shoe was no longer anchored on one end, the manufacturers started making the linings different also. There is a Primary shoe (front) and a Secondary shoe(rear) at each wheel . The primary shoe was identified by the word primary marked onto the new lining or it was always the 2 shoes in a set with the shorter lining applied to them. The primary shoe lining material was a slightly different composition than the rear shoe. It was slightly softer or more "grabby" than the Secondary shoe. When the brake was applied both shoes move outward until they contact the rotating drum. The shoes then rotate toward the anchor pin. This action wedges the secondary shoe to the drum. For a more even brake wear and life they changed the asbestos mixture of material and the length on the primary versus the secondary shoes to get the most durability/life in the small space. I still have old lining sets that I keep for my antiques that are marked with ink "primary" and "secondary" in the boxes. Many times through the 70's, 80's and into the 90's I would see both primary shoes on one side of a vehicle or the primary shoe mounted on the rear of the wheel. They were always visibly worn harder than the secondary shoes were. 

  23. Hello Greg. I know you have been having issues with your car running correctly for a while. One thing to check that is often overlooked is the ignition coil, specifically the primary side wiring (small low - voltage wiring). If the ground side of the battery is positive polarity then the small wire that comes off the coil going to the distributor/points should be on the side of the coil with a + or something to indicate the polarity. if the battery has been hooked up with a negative ground then the coil primary lead going to the distributor/points must be connected to the - side on the coil. Years ago I hooked one up incorrectly and the engine runs anything but correctly. Changing the ignition timing out of specification makes them run better but not even close to decent. Take a look at the coil polarity and get back to us, Best of luck to you. 


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