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Vacuum tank - 1993 Honda Acty HA4 5-speed manual

Discussion in 'Honda Acty' started by Minitruckin93, Nov 19, 2020.

  1. Minitruckin93

    Minitruckin93 New Member

    Hello, I recently purchased my first minitruck, a 93 ha4 manual transmission. I’m in the process of performing tune up and maintenance items to get this truck as reliable as possible. So far I’ve done fluids, timing belt, water pump, spark plugs, distributor cap and rotor, fuel filter, tires, and front springs. The truck starts every time and idles fine, the only problem I’m having so far is sluggish hesitation when throttle is applied when the truck is cold. In the process of checking and replacing vacuum lines. I’m stumped by this “vacuum tank” located on top of the intake manifold with 2 fittings on it. Seems like it’s supposed to control an actuator on the choke. I don’t get any vacuum at the actuator at any rpm. The tank is also filled with a fluid but I can’t imagine that’s normal. Tried applying vacuum to both ports and it just holds vacuum. Is this normal? Found fuel in the line from the power valve so suspecting this may be the source of my hesitation. The line to the power valve does hold vacuum though which might not happen if the diaphragm was torn, not really sure. Thanks for any help in advance and thanks for this wonderful resource,

    Attached Files:

  2. shogun

    shogun Active Member

  3. Jim Nelson

    Jim Nelson Active Member

    I don't know anything about Hondas,never even seen one, but with the fittings on yours and you mentioning a relationship to the choke could it be that, like many other Brands, the choke is heat activated and this is some kind of reservoir related to that?
  4. Limestone

    Limestone Well-Known Member

    Sounds logical to me! I'm in the same boat. Maybe someone a little more familiar with these units can chime in!
  5. Minitruckin93

    Minitruckin93 New Member

    The manual calls it a vacuum tank. Couldn’t find any references in regards to the Acty but did find it mentioned in a separate Honda forum. According to that it’s a storage tank for vacuum to be used by the engine at times when it produces low vacuum. Not sure if that’s what this is or not. In my original photo the white fitting goes to manifold and the black fitting goes to the actuator with the black top in my photo from this post. The white fitting on the tank seems to be plugged with some sort of brass fitting that looks like it’s supposed to be there but doesn’t allow air to pass through. I’ve tried cleaning both fittings but still can’t get the actuator to move. If anyone could tell me what that actuator controls I would really appreciate it.

    Attached Files:

  6. Jim Nelson

    Jim Nelson Active Member

    Wow, and I thought Suzuki's were weird with their vacuum systems. Surely there is someone around here that understands them since there are so many around.
  7. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    THe Hijets have one as part of the 4wd, and locking axle vacuum systems. I haven't seen one as part of an engine management systems.

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