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Vapor lock

Discussion in '40- & 55-Series Tech' started by Cruiserhead05, Jul 8, 2003.

  1. Cruiserhead05

    Cruiserhead05 SILVER Star

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    i seem to have a very bad case of vapor lock when it shot outside and i'm doing highway speeds. alot of poeple seem to know about vapor lock but does anyone have a been solution to fixing it. could i wrap the fuel line is something to keep off the heat..
     
  2. FJAfrica

    FJAfrica

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    I eventually removed the steel fuel pipe from the pump to the carb. Replaced it with a suitable rubber one and ran it over the engine, away from the heat. Seems to have solved that problem for me.
     
  3. srafj40

    srafj40

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    Bump.

    CHo5, I will post some pics this weekend as to what I did to reroute the fuel line away from the block. Stay tuned.

    Stacey
     
  4. srafj40

    srafj40

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    OK, this is also for some folks at cruizers.com. I am no poto shop wiz so please excuse the high tech arrow. LOL

    Old metal fuel line; you can see it goes under the air filter.
    [img width=300 height=260]C:\My Documents\My Albums\DSCF0098_0001.JPG[/img]

    It comes out and attaches at the back union area between the carb and air filter.
    [img width=300 height=260]C:\My Documents\My Albums\DSCF0099_0001.JPG[/img]
     
  5. srafj40

    srafj40

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    I cut the line and ran it like this;
    [img width=300 height=260]C:\My Documents\My Albums\DSCF0101_0001.JPG[/img]

    In fromt of the RAD;
    [img width=300 height=260]C:\My Documents\My Albums\DSCF0102_0001.JPG[/img]
     
  6. srafj40

    srafj40

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    Lastly I came in from the right side. I moved the union from between the carb and air filter and went to the front entry;
    [img width=300 height=260]C:\My Documents\My Albums\DSCF0103_0001.JPG[/img]

    This is what happens when your wife works on weekends and does not have proper oversight of her husband. LOL

    I hope that this can help some vapor lock victims. Here in Tucson, I now only have problems when it is over say 103 or so and I have been driving for 20 plus minutes. I think that problem is the filter.

    Stacey
     
  7. Spencer

    Spencer

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    I have a vapor lock problem also. Questions: There is a fan on the left fender (1978 FJ40 with all of the emission stuff removed) that "blows" on the carb. If this is working, will this help prevent vapor lock? Also, my exhaust pipe is reduced in size just below the exhause header. I am not sure if this is stock - could this "restricted" exhaust pipe be causing heat build-up and vapor lock?
     
  8. srafj40

    srafj40

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    Spencer,

    Are you refering to the infamous carb cooling fan?

    I do not know what year the carb cooling fan was introduced to the 40. I think post 1978 or so.

    Stacey
     
  9. CruisinGA

    CruisinGA

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    Stacey, I believe he is. My friends '78 40 has one as well.
     
  10. Spencer

    Spencer

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    [quote author=srafj40 link=board=1;threadid=39;start=0#msg28256 date=1058824449]
    Spencer,

    Are you refering to the infamous carb cooling fan?

    I do not know what year the carb cooling fan was introduced to the 40. I think post 1978 or so.

    Stacey
    [/quote]
     
  11. srafj40

    srafj40

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    Spencer,

    If that is what you are talking about, the carb-cooloing fan ONLY runs after the ignition is off. It blows air on the carb while the vehicle sits to keep the fuel from vaporizing in the carb.

    I have looked into retro fitting a fan. There is an important relay missing that must be added. I do not feel confident enough to splice into my wiring harness.

    Stacey
    BTW- thanks guys for telling the ROOK that the pics did not post. (Nelson pointing finger; "HAH HAH")
     
  12. Spencer

    Spencer

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    The fan is on my Cruiser, it's just not working. After looking through the S.O.R. catalog last night, it looks like there is a temperature sensor on the manifold somewhere below the mainifold and a relay - these work to turn on the fan. It makes sense that the fan only runs when the engine is off, because the problem gets worse after the engine is cut off hot and sits for a short time. I am planning to check out the fan. relay and sensor to try to get the carb fan system working again.
     
  13. srafj40

    srafj40

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  14. Spencer

    Spencer

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    Thanks for the help. It would not have occured to me that the fan only runs when the ignition is off. You probably saved us a lot of time trouble shooting the problem.

    Spencer
     
  15. FJAfrica

    FJAfrica

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    I fitted my own fan, originally came from a boat, engine room blower, rigged it with a switch in the cab. Works like a charm on those real hot days when I am crawling.
     
  16. srafj40

    srafj40

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    Fjafrica,

    Does it look something like this; (in the lower left corner red/black sticker)?
    [​IMG]

    So is it a manual fan only?

    Stacey
     
  17. FJAfrica

    FJAfrica

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    No, I'd send a pic, but I dropped my camera into a mud pool while wheeling, it is not the flat fan type, but rather one mounted into a tube, about 4" in diameter. I pull the air from the side vent. That fan in your pic should do the trick though? Currently mine is only manual, only turn it on when crawling, that's when things get real hot under there, actually looked into the little level glass on the carb on one real hot day, only to see the gas boiling in the bowl :eek: That's when I decide to reroute the fuel line and add the fan. Since then, I have had no trouble with it.
     
  18. FJAfrica

    FJAfrica

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    PS. My master cylinder and steering box sits on the other side of the engine, so everything is clear around my carb. --- Right hand drive ::)
     
  19. Spencer

    Spencer

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    According to the electrical diagrams in the Haynes manual, there is a thermal sensor in the manifold and a relay/timer that activates the carb cooling fan. There is also an inline fuse shown on the electrical diagram. We have found the thermal sensor, but neither the Haynes manual or the Toyota repair manuals are clear as to where relay/timer is located or what it looks like. I have checked the fan motor and it is ok, so the problem must be in the relay or the thermal sensor. Can anyone help on where to find and how to test the relay/timer?