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DanielC

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About DanielC

  • Rank
    Senior Member
  • Birthday 09/01/1954

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  • Gender
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  • Location
    West Linn,Or
  • Cars
    521's Ford Aerostar
  • Interests
    Watersking

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  1. DanielC

    Floor Pan Repair

    See this thread, is is about my work on replacing the floor pans in a 521. I know, you have a 320, but the principles are the same. There is also a lot of comments from Ratsun member Wayno, he has done work on 320 trucks. https://ratsun.net/topic/51593-floor-repair/ Ridges can be fabricated in a flat piece of sheet metal with a bead roller. This is one source of metal fab tools and equipment. https://www.eastwood.com/
  2. DanielC

    L18 bore 30 over

    "Dont let them bore the cylinders till you have the pistons.... just my opinion..... " Not really an opinion, more of a necessity.
  3. I would look at the engine block, just below the number 3/4spark plugs. stamped is the engine type, L-16, L-18, or L-20-B, then the serial number. If the PCV valve is missing, or the wrong one, that may allow some oil to get in to the intake manifold.
  4. By refrigerant, I think you mean coolant, the radiator, engine cooling. Refrigerant, at least in USA English, is used in air conditioning. My opinion, the compression is a little low. It may be time to rebuild, or get another engine. Here in the USA, I can usually wait for a useble engine to show up in a junk yard. You know Argentina's options for auto repair much more than I do.
  5. I do not know how long you have had your Datsun, or if you have a L-18, or a L-20-B engine. The L-18 is factory stock, but lets be real, the engine has probably been changed, or had some work since 1974. Your truck could also have had a L-16 engine swapped in to it. Datsun engines in this time period are completely different than the engine in your Bronco. Datsun engines like RPM. If you are trying to make your Datsun engine have immediate response, in gear, it is simply not going to happen if you mash the throttle at 1,500 RPM, or even much below 2,500, even with a more torquey L-20-B. The L-16, 3,000 minimum. On the other hand, the L-16 will run up to 6,500 easily, and the L-20-B engine will run up to around 6,000. The L-18 has slightly torque than the L-16, but runs closer to the L-16 RPM range. What is the compression of the engine? Should be around 160, or higher, and even in all four cylinders. A carburetor measures fuel based on only one factor, "how fast is the air moving through the venturi?" If you mash the throttle at a low RPM, the velocity of the air moving through the venturi drops so low, that the carb cannot meter the gasoline accurately going into the engine. Also, air is light and suddenly opening the throttle causes a lot of air to rush into the manifold, and because gasoline is a heavy liquid, compared to air, almost all carburetors have an accelerator pump that mechanically squirts gasoline into the manifold, to cover the dead spot until the heavy gasoline starts flowing, and catches up with the increased air flow. As mentioned, a stock Datsun carburetor has a vacuum secondary. On a vacuum secondary carburetor, even on a V-8, the manifold vacuum is not used to open the secondary. The secondary opens based on the vacuum developed in the primary venturi, and the primary venturi does not develop much vacuum until the RPM is up high enough to get enough air flow through the engine. This is to allow the primary to accurately meter the gasoline, until there is enough air flow demand from the engine to have adequate airflow through the secondary of the carburetor. A mechanical secondary Weber will have a big bogging problem if you mash the throttle, because both carb throats open if you mash the pedal, and even if you did put a accelerator pump on the secondary, the engine will not have enough RPM (and air flow) to meter the gas correctly, until the RPM gets higher. Check the compression. Adjust the valves. Set the timing, about 10 degrees BTDC at a low idle, below 600 RPM, vacuum advance disconnected, and plugged. If the idle is faster, mechanical advance starts to come in, and you cannot set the initial timing correctly. After you do all the other tune up stuff, then you can adjust the carb, AFTER the engine is warm. Remember the Datsun engines like RPM. If you want, or need quick throttle response, you have to be in the correct lower gear to get it. You have to plan ahead to have the correct gear to have enough RPM (above 3,000, and this number is with a vacuum secondary carb) to get good throttle response.
  6. Nice, but the tail lights are on the wrong side. The metal tail light frame is right and left specific, and the clear plastic reverse light lens is right and left specific, but all the other tail light parts are the same right and left. See this thread about 521 tail light rebuilding. https://ratsun.net/topic/18092-521-taillight-rebuilding/
  7. First, try turning the crankshaft one complete turn, this turns the camshaft, and fuel pump eccentric a half turn. you might just have the camshaft turned so the eccentric is closest to the fuel pump. Six bolts, and the cam cover comes off, so you can see what is going on. The fuel pump must have a plastic spacer in between the pump mounting flange, and the cylinder head.
  8. DanielC

    Tacho help

    Mike, you missed... Lucas, Prince of Darkness
  9. See this thread. https://ratsun.net/topic/61167-how-i-replaced-a-521-exhaust-system/
  10. DanielC

    L20B in a 521

    Use the stock L-16 oil pan on the L-20-B engine. It matches the 521 frame. Use the throwout collar and bearing for the L-20-b engine, it matches the pressure plate. I like to use the stock 521 throwout lever, with a spring. Use the metal engine mount brackets off the L-16 engine on the L-20-B engine, Use the 521 rubber engine mounts. After the engine mounts are bolted into place, then fabricate the transmission mount. See this page, near the bottom for transmission mount details. https://ratsun.net/topic/30606-my-ratsun-datsun-521-now-with-l-20-b-and-a-five-speed/?page=21 The stock 521 speedometer cable can be routed over the top of the transmission, to fit the transmission speedometer pinion. After the transmission mount is done, then you can get a measurement on the length of the front half of the driveshaft. The driveshaft will need to be rebalanced as a unit. The factory service manual specifies a maximum unbalance of 15 gm-cm or 0.2 In-Oz at 4,000 RPM. 4,000 RPM is the approximate RPM of the driveshaft at 60 MPH. The L-20-B engine is taller than the L-16. On my 521, the rod that holds the hood open rattled on the air cleaner of the L-20-B engine, I took it off, and just carry the hood stay open rod in the truck. Even if you use the L-16 two bottom port exhaust manifold on the L-20-B engine, you may need to modify the exhaust slightly, because the exhaust manifold is about 3/4 of an inch higher on the L-20-B engine.
  11. Thanks again for tips on removing brake boosters from 620 trucks. The local Pick-n-Pull has a 1979 620 truck, and this morning I removed the brake booster, and master cylinder from that truck. I also got the differential carrier, hoping for a 4.11 rear axle. Yesterday, I removed the speed pinion, it was red. After bringing the differential carrier home, I did the math, 35/8. It is a 4.375 ratio. I think this is the bigger booster. Can I use the pedestal with the booster I got with the smaller brake booster?
  12. It is hard to test for high NOx, because you need to put a load on the engine to get the cylinder pressures high enough to make NOx.
  13. This is going to get into the weeds a little bit. EGR should not have much of an effect on either CO or HC emissions. EGR is used to limit NOx (nitrogen oxide) emissions. The main cause of high CO is too rich, too much fuel, not enough oxygen to burn all the carbon in the gasoline completely. The main cause of high HC (unburnt gasoline) is a condition called lean misfire. There is simply not any gasoline vapors by the spark plug, so when the spark happens, nothing burns. Nitrogen Oxide emissions are caused by high cylinder temperatures during combustion after the spark plug fires. If you can remember gas laws from high school chemistry, high temperatures in a gas mean high pressure. For an engine to make a certain amount of horsepower at a given RPM, it has to have a set amount of torque, or in other words, a set amount of cylinder pressure. Adding EGR to the fuel air mix going into the engine cylinders reduces the temperature of combustion. This reduces the cylinder pressure. But you still need the same amount of power as before to maintain speed going down the road, so you open the throttle more to increase the cylinder pressure with EGR added to the fuel mxture. The cylinder pressure, and temperature basically stays the same, but with EGR, you are adding more fuel and air mixture (Lower Vacuum) to get the same power as before.
  14. Thanks for booster, and pedestal removal tips, guys!
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