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Completely lost power in forward gears

Discussion in 'Honda Acty' started by Brett Toney, Sep 7, 2021.

  1. Brett Toney

    Brett Toney New Member

    I have a 1988 acty 550, 4apd, 2wd4wd, ultra low, low reverse, locking differential, and no air solenoid I can find on my carb.

    my acty felt like it needed a tuneup for awhile. But I’ve been driving it daily.

    I ran outta gas, and fueled up but had no power in my forward gears, Aside from 1st which felt fine.

    *I can normally easily crawl up my driveway in 1st and the hill below my house in 4th*

    Replaced fuel filter, plugs, wires, plug wires don’t feel like they reach to snap on the plugs no matter what I try.

    Felt like it helped but still felt like it was sticky engaging the gears so I:

    cleaned the dist cap, cleared the cat, pulled the carb and cleaned jets.
    One of the flanges? In the carb was a bit sticky closing, but after cleaning the carb it moved smoothly.
    Found a broken grounding strap from Fran to engine.
    All felt back power back, aside from 4th felt whimpy.

    found a tiny oring I think maybe goes to the fuel cutoff solenoid, so took carb off and put oring on the solenoid.
    Found 3 disconnected vacuum lines i reattached.

    Drove and overheated for the first time ever.
    Temp gauge all way to right.
    I put I didn’t tighten the top nut (1 of 2) securing the carb to the engine.
    As I found our by the pouring coolant like my truck was about to give birth. tightend the carb back up.
    Don’t know how to check the choke.
    Tried burping coolant system but couldn’t, replaced the thermostat,
    Had to manually all coolant to top of engine and hoses to burp. But burped that shit.
    The giving it a little throttle the bleeders on top will slowly weep coolant, ones by the spare tire will pour and spurt if the bolt is completely out
    Temperature is good.
    No big leaks aside from the constant oil leak from idk where?
    All gears are there but 4th has no power under load.
    Actually 1-3 also feel a little rubber-bandy when they engage, but they eventually get with it and I think I have full power in those gears….

    Then a few hours later. I drive home and this thing takes a million years for 1st to give me any power and second and third and have to take my hill in 3rd instead of 4th. I then couldn’t make it Up the driveway in 1st, had to get a run in reverse. No power in forward gears.
    Also found this carburetor looking oring or gasket it’s tanish brownish hard plastic looks about the size of the carb intakes or similar. ….
    Any advice?
     
    Last edited: Sep 7, 2021
  2. Brett Toney

    Brett Toney New Member

    Also, the engine compartment always smells gassier than I think it should.
     
  3. have you checked the air tubes/ air filter ? try disconnecting the air tube from carb and let it open to air and test drive?
     
  4. Brett Toney

    Brett Toney New Member

    Yep, no effect on the issues.

    I know nothing but really wonder if it could be choke, or vacuum related.

    also, while looking for loose vacuum lines today I’m wondering if the vacuum lines that don’t bother the engine when I disconnect them or don’t have any vacuum are clogged or hooked up wrong, not sure if that could be part of it.
    when at the froward top (driver side) of the engine compartment near a black box, I got electrocuted. Not shocked, straight up couldn’t remove my arm idk if I touched a connector, but I almost just think I just touched the frame.
     
    Last edited: Sep 7, 2021
  5. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    You ran out of fuel, and it suddenly started running like it is too lean. Which indicates that there is a fuel restriction. First thing to check is fuel filters. You did right with that. But, the next thing to check is the needle and seat. And, there may be a fine mesh filter internally in the carb to protect it, which is clogged.
     
    Limestone likes this.
  6. Brett Toney

    Brett Toney New Member

    I disassembled and douched the carb outbwith carb cleaner twice, no improvement.

    Im curious about this thing on top of the carb with the vacuum line on it idk if it’s working correctly?
    Also curious if it could be vacuum lines or another part of the fuel system
    Even today after redoing everything, still same problem
    Shit into first fine, second kinda almost works but fees like it’s not gonna, third same as second, 4th is completely gutless
    But I was able to get up my driveway in 1st, which I couldn’t last night… idk….

    8C4E720C-5DFB-4DB7-8015-EFF8D0773A7C.jpeg
     
  7. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    That vacuum can adjust something on the carb, based on the vacuum level at the manifold, or a controlled port from the carb, and can be used for a lot of things. Typically it pulls off the choke as the engine warms up. it can also be used to bump up the idle speed, if you turn on the air conditioner, etc.

    Coupled with various retarder, and check canisters of various ratings, they can adjust for a lot of operating dynamics to give better control of the air fuel ratio.

    I’m guessing that the one in your photo is the one hooked to the choke system and pulls the choke off as the engine warms up.

    G and R Imports@ https://www.grimports.com/ ,has a very good maintenance tips page. Which includes photos of most of the carbs with labeling of what things are.

    Answering questions on the forum is difficult, in that I’m never sure what level of actual mechanical skill and knowledge folks have. For some they have wrenched on things from teh sixties forward, and have a great deal of breadth and depth of experience with engines and how they work. And, many folks, this is the first time they have actually tried to work on anything, and it is hard to have an informed discussion, due to their lack of even basic terminology.

    Couple that with folks that have just enough knowledge to give bad advice, and it gets really difficult.

    It ran out of gas, and has run badly since. So what could have changed, solely from teh junk in the bottom of the tank getting sucked into the fuel lines? Usual suspects are: Clogged filters or lines; something in the needle valve or passages in the carb.

    Starting with filters, there are typically a sock filter in the tank, an inline fuel filter, and in the carb of most of the minitrucks. If any of them are clanged you’ll run lean, and not have power. On my Hijet, I pulled the sock filter in the tank, and put a clear glass filer with renewable elements, in the suction line from the tank, just as the line leaves the tank. That is a very good solution on my truck, because I have a tip/picker bed, and can raise it, to conveniently check and service that filter. Not so much on other folks.

    The other thing that could have been impacted by crud in the lines, is valves. How and where is the fuel pressure regulated? With an in-tank electric pump, it can be in the tank right after the fuel pump, fuel just recycles in the tank, to keep the pressure stable, and if that gets jammed will never close, resulting in low fuel pressure. On the Hijets the pressure regulation occurs at the fuel pump on the engine. On mine that valve got something in it, and the fuel pressure was too low.

    There are several thing that can go wrong, and trouble shooting is going through things one thing at a time, in a systematic process. Sometimes your knowledge and experience, allow you to find the problems fast, and sometimes it take a while.
     
  8. Brett Toney

    Brett Toney New Member

    Thanks for the resource! I’ve spent about 10 hours a day for the last two weeks under this thing.
    I’m for sure not a mechanic, nor is there one in the area that will touch a kei truck so it’s up to me..
    It’s sad because aside from the clutch starting to shit out this summer, it ran strong even with a partially blocked cat, and three unhooked vac lines the entire time I’ve had it.
    After changing out and cleaning everything I did twice, It sounds so smooth and happy until I try and drive.

    there are lines that looks like they should be vacuum lines (I’m not sure) that never seem to have any vacuum.

    I don’t know if I have or how to check: fully functioning vac system, timing, compression, or good spark. The last thing I know I can do is disconnect the fuel line at the carb, start the fuel pump for 1 minute and measure it’s volume per the service manual, if pressure is correct at the carb then at least I know the fuel system is correct up to the carb.
    a lot of the shit in that book goes over my head….
     
  9. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    You need to get one of these: https://www.amazon.com/Carburetor-V...m+tester+gauge+test+kit&qid=1631202004&sr=8-1

    Plus, a timing light, and some kind of tuneup meter.

    There should be a vacuum diagram floating around the forum somewhere for your truck. Find it, and replace all of the vacuum hoses, with new silicone ones, (the trucks are getting older, and the factory hoses are getting hard enough they don’t always stay on the nipples) following the routing on diagram. some of the vacuum comes from the intake manifold, but some of those run through thermostatic valves, which open or close, depending on how warm the engine is. And there are definitely ported vacuum leads coming from the carb, which have vacuum depending on how open the main butterfly valve in the carb is.

    Never worked on any of the minis besides my Hijet. But there are only certain ways to achieve a set of standard goals on an emissions controlled engine, and the dominant technology for that until they went to fuel injection was vacuum controlling the timing, and the air fuel mixture. When different engineers have to solve essentially the same problem, the physics and chemistry take over and drive the design. So, while every engineer comes up with their own solution, you end up with a lot of commonality.
     
  10. Brett Toney

    Brett Toney New Member

    So Applied vacuum to my egr valve The only way I could which was using my mouth and there was a bunch of awful tasting fluid that extracted from that EGR valve. Is there anyway for me to use blower or air or vacuum to get any fluid or whatever might be in the system completely blown out?
     
  11. Brett Toney

    Brett Toney New Member

    when I apply power to the little actuator in the control box I can blow or suck through one of the tubes but the other one remains close no matter what. And I can’t tell whether or not it’s working correctly
    04AB84F6-82FB-4DB6-8228-9D350CC793AB.jpeg
     
  12. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    The one with a twenty on it provides vacuum to the solenoid activated vacuum valve. The other is going to a diaphragm. If you apply vacuum to the 20 line, nothing should happen, unless the valve is bad, or is a normally open. Pull vacuum on the other line and the diaphragm should contract, and you hold see the spring moving.
     
  13. Brett Toney

    Brett Toney New Member

    Still diagnosing the problem.
    Deleted cat
    My head gasket was is for sure bad. Had tons of white in exhaust.

    Put bar’s leaks head gasket fix in and the white has dissipated. But still bogs down when it should hit its power band in the gear…

    also my differential light came on. Not the one on the button, the one that comes on when it engages…… can’t make it go off


    Drained fuel, system
    Gas was good.
    Replaced gas

    spark is good

    if I pull the fuel line off the carb and turn the ignition, the fuel pump spurt spurts spurts plenty of fuel.

    egr valve seemed good, not sure how to tets the others, but I
    Do think the valve on top of the carb might not be getting vacuum correctly, or might have a bad diapraghm? Not sure where and what and how to test valves in the vacuum system. But something there in the system or valve sis suspect

    need to Figure out how to use the timing gun and compression tester.
     
  14. ncovi

    ncovi Member

    Having a similar issue here Brett, completely replaced Carb, ignitor, plugs, air filter, fuel filter (several times) It will wake up after a 2 mile luggish drive but acts like it is flooding out perhaps (and the plugs are dark carbon filled) replace the plugs and in minutes similar. I can get the RPM high if I baby it just right then once it is under power it will lug again. Warm-up time does not affect this issue. I cannot figure this one out. Any chance you have found a resolution?
     
  15. ncovi

    ncovi Member

    Thanks for the response Brett, the choke idle starts off great and settles down as it warms up all indicators appear to be that it's functioning fine until it goes under load and you lose your RPMs. perhaps I will look at changing the distributor next I'm not sure what to do with this point but I appreciate your response
     

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