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Everything posted by hchris

  1. Correct - having said that, with fuel injection and engine management systems plus the ability to lean out the mixture in cruise they`re not too bad.
  2. And the thing about (light) aircraft engines in the main, is that max rpm is generally around 2700 - 2800 and for cruise 2300 - 2500. Typical Cessna/Piper run 160 - 180hp, so overall they are pretty low stressed engines, the design emphasis is really on big bore, big torque and low revs, not forgetting that a boxer configuration makes it easier to cowl and streamline. Different story when you get into turbocharged and higher output engines, using 98/100 octane low lead.
  3. Correct, distributor vac is drawn above the throttle.
  4. If you have an accessible vac port hookup a vac guage and see how it's behaving, great diagnostic tool.
  5. hchris

    starter trouble

    Have you tried another battery or used jumper leads to another battery ?
  6. Plenty of home made cheap and effetive centralising tools out there, do a search.
  7. Have you centralised the shoes ? Chrysler/Dodge/Plymouth brakes require that you get the shoes concentric in the drum before anything else, it's complicated if you don't have the right tool, plenty written up about it.
  8. There are some people who shouldn't be allowed near cars..😥
  9. During the casting process an open ended passage is formed, there's more than one of these within most carbs, so these plugs are used to close off the internal passages for fuel and airways to function. Where there's a need access these passages in service for cleaning etc you will find a removable/replaceable aluminium plug, and of course at the other end of the passages are jets or vacuum ports as required.
  10. When vaccum is drawing fuel into the upper housing of the tank you will feel the feed pipe go cool/cold, then warm up when the flow stops; the temperature changes are not drastic but you can feel the difference with your hand. The other indicator, if you listen carefully at idle, is the change in engine revs as the vac cuts in and out in time with the fuel being drawn into the tank. Beyond these indications there's not much else other than opening up the tank after the engine has been running.
  11. Yep, that would be an access panel to the fuel cap. There would have been an extension pipe from the standard filler opening in the beaver panel, the extension would pass up through the bottom of the aftermarket trunk.
  12. Re the heat shield, generally it's an add on piece of folded sheet metal to cover the pump and shield it from the heat radiated by the exhaust manifold. It's held in place by utilising nearby bolts or studs.
  13. Yep you got me there, but my point really was just try another condenser, save messing with the multi meter.
  14. Or perhaps just spend a buck or two on a new condenser (20 - 30 uf) and hook it up as Trini says anywhere on the distributor, so long as it's in the primary circuit to the points. Saves messing around with the multi meter. ,
  15. Aand of course what everyone keeps forgetting is the fuels today are light years away from that available when those cars were built. The issue of having a starting mixture that's vaporizing enough when it's cold will always be a problem, there's little relevance in what happened when "Dad" owned the car back in the day.
  16. hchris

    Timing Engine

    Have you considered just moving the plug wires to suit proper firing order, if as you say you're 180 out, just swap the wires from 1 to 4 etc. Reading your problem again, were you in fact at TDC #4 instead of TDC #1 when you viewed those timing marks, remember the cam turns at 1/2 crank speed
  17. The oil bath cleaner is not significant, the issue really centres around the throttle plate area, the laws of physics dictate that a venturi affect, small throttle opening, moist air and the chill effect of vaporising fuel create the ideal conditions for ice to form and build up around the throttle plate, this will only last as long as the combination of the above effects prevail. What changes these conditions is warmer air around the throttle plate as the engine itself warms up, a combination of manifold heat plus warmer under hood air entering the carb intake. You mention not being cold enough, the fact is that the temperature of the air will drop rapidly as it passes through the venturi (physics again) with a moisture (humidity) content carrying the necessary icing component, I reiterate that the ideal conditions are about 10 - 20 degrees ambient above freezing to 5 - 10 degrees below freezing, the humidity content is a major influence in this range In fact in the Arctic the problem isn't as bad simply because the air is dryer, certainly colder but dryer thus no moisture to freeze. So what to do; the easiest thing is introduce some warm air into the air cleaner intake. I have (a not very pretty) flexible duct with one end just above the exhaust manifold and the other pushed into the air cleaner nozzle. With an oil bath cleaner this isn't easy to do, but I have seen where someone drilled some holes in the upper out side of the casing and fashioned a fixture to accept a piece of flex duct to the side of the air cleaner, again not pretty. With this approach of course, you don't want it there when the weather warms up as the other laws of physics could lead to detonation with the intake of too much hot air. Finally, forgetting about the physics, just live with the problem and adapt your driving to accommodate it. In all of the above of course, your problem might not be icing at all !!
  18. Exactly what I was thinking , classic symptom. First few minutes of running causes a large chill factor across the throttle plate, due to low pressure and high velocities through the venturi, mix this with cold fuel, cool air and moisture you've created a perfect refrigeration effect. As the manifold and carb base warm up the symptoms disappear, modern fuels are part of the problem as they are more prone to this condition. If you are able; first start of the morning feel the carb base on and off for a minute or two, you will feel the chill as it happens, in severe cases you can actually see an ice ring form around the carb base on the outside. Without wanting to bang on too much, throttle ice is most likely to occur 10 to 15 degrees ambient above freezing point and is influenced by the moisture content in the air, any of you aviators reading this will know what I'm talking about.
  19. The fact remains that if you fit bearings that don't conform precisely to the crankshaft dimensions then you have every chance of damaging the crankshaft, and then you're back to where you started.
  20. hchris

    Vacuum tank problem

    Okay, but as stated above what about the valves and vents in the top housing?
  21. As Tom has said, the sensor to gauge is a sealed unit. If you break any of the connections the enclosed fluid will escape and it's really a specialist job to repair, or if you are an industrial chemist, avery tricky job.
  22. hchris

    Vacuum tank problem

    The critical areas for these tanks are the top housing, which usually develop cracks or warp and, the seating of the valves in the upper housing , along with the springs and fulcrum levers etc.
  23. Okay, having had the crankshaft reground would mean the bearings actually need to match the newly machined crankshaft pin dimensions. ie you're probably needing specific under size bearing shells. Using second hand bearings in this instance would undo the money you've just invested in the crankshaft.
  24. Depends on the clearances and existing wear patterns of shaft and bearings. If you're just putting together pieces that have been disassembled from the same location, not a problem, if you have part wornn bearings and crank pins that need just a light polish/linish, not a problem; beyond these parameters not such a good idea.