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On gen 1 do u block upper or lower grill

Discussion in 'Generation 1 Prius Discussion' started by cabral255, Nov 9, 2011.

  1. cabral255

    cabral255 Junior Member

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    Or both
     
  2. cabral255

    cabral255 Junior Member

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    Which grill do i block, upper lower or both?

    My car is a gen 1, and I have posted this message on there to but not many people go on that forum anymore. Does anyone have the answer? i don't want to overheat and damage the inverter. Thanks, Jay
     
  3. mlibanio

    mlibanio Member

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    Re: Which grill do i block, upper lower or both?

    Use swimming pool noodles to block off the bottom. I have been doing it for years, with no issue. You can keep it on between 5 celsius and lower without overheating issues. Look in my Gallery, I am sure I have a pic or two with it on.
     
  4. thephoenix

    thephoenix New Member

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    I use foam pipe insulation and I block the two lower openings and I cut some insulation to fit in the two smaller opening right under the hood I've never had a problem over the years I've had my Gen I
     
  5. jhknight

    jhknight Junior Member

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    Me too! Foam pipe insulation fits perfectly!
     
  6. WHCSC

    WHCSC Member

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    How do you hold the insulation in there? Does it just fit tight enough to stay by itself?
     
  7. trseven

    trseven Junior Member

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    I used pipe insulation also, top and just one across the bottom. They stayed on fine by themselves until I forgot and went through a car wash. Lost the bottom one!

    Gerry
     
  8. asinc

    asinc Junior Member

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    Whats the reason for blocking the grills?
     
  9. WHCSC

    WHCSC Member

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    To help the ICE warm up faster
     
  10. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Also, at highway speeds it reduces the drag from excess, dense, cold air going through the engine compartment. If you ever get a chance to drive a long distance through dry, sub-freezing weather, try it on cruise control and change out the lower inlet block say every 10 or so miles. I remember seeing nearly a 4-5 MPG decrease at 65 mph between with and without the radiator block in air in the 20-30F range, dry pavement. The effect decreases as the air warms and becomes less dense so I don't worry about it once it reaches around 60F.

    Bob Wilson
     
  11. ChapmanF

    ChapmanF Senior Member

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    Here's a little different approach I've been using for 4 years:
    gb0.jpg
    It's a sheet of heavyish vinyl stair tread protector from the hardware store. When I first made it I did not have a ScanGauge (or any way to watch coolant temps) so in what might have been an excess of caution I made some holes across the bottom where they would allow some extra airflow through the inverter radiator and the bottom of the main one.

    The metal strip you see on one edge (click the thumbnail) is a length of spring-bronze door weatherstrip from the same hardware store, folded in half lengthwise over the edge of the vinyl. With a piece of wood underneath I just used an awl and a hammer to drive some dimples through the top fold of bronze, the vinyl, and the bottom fold, and that attached it securely enough.

    It's there to keep that edge straight and stiff while I feed it through from one side:
    gb1.jpg
    I just roll it up with the stiffened edge out, slip the whole roll down behind the grille, and start unrolling it, feeding the stiffened edge across behind the hood latch over to the other side. That places the curtain ahead of the main radiator but behind the inverter radiator, so inverter cooling isn't likely to be an issue; just watch the engine coolant temps.
    gb2.jpg
    All unrolled, just a little extra tail left curled around at this end.
    gb3.jpg
    And the stiffened edge fed all the way across. It's a stealth grille block! Pretty much invisible if you're not looking for it.

    In the spring I just re-roll it on the passenger side and lift the roll out from behind the grille, and stash it in the trunk for fall.

    Since getting a ScanGauge I've been less concerned about it blocking the grille too much. Coolant temps seem to stay well controlled with ambients at least up to 50 or 60 F. I doubt I even needed to make the holes in it. Last spring when the warm snap came I was caught by surprise and didn't remember to take the grille block out until I was wondering why the A/C didn't blow very cold....

    A not-too-cool day for installing or removing the curtain is best, because the rolling/unrolling gets challenging if the vinyl is cold and stiff.

    -Chap
     
    WHCSC and bwilson4web like this.
  12. joedirte

    joedirte Member

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    I was wondering, would it be a good idea to have some holes cut in in strategic locations. I'm worried about the electric fans burning out. I supposed the fan shrouds and distance from radiator means that they can run without too much worry if the radiator was totally blocked. Just wondering if anyone thought this was a concern.
     
  13. ChapmanF

    ChapmanF Senior Member

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    Fans aren't even powered unless coolant temp hits 95 C (if I recall correctly) or you are running the A/C, neither of which is likely during the season you'd be likely to have a grille block. The thermostat opens at 82 C (fully open by 85) and in cool weather even with the grille blocked I really don't see the temp on the scangauge go above 85 C.

    The holes I did cut in it are there because I didn't have a scangauge at the time. Since getting one and being able to watch the temps, if I were making it over again I don't think I would bother with holes at all. Anyway, if the scangauge ever showed me a temp heading toward 90 C, I would just pull over somewhere and take the grille block out.

    -Chap
     
  14. joedirte

    joedirte Member

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    What if you turned on defrosters to get rid of condensation.. or maybe idling in a parking garage.. I suppose the ICE would shut off before the fans needed to run unless you somehow forced ICE to run. I was just curious what happens to the fans with grills blocked, like a warm snap or something. Anyways it is a great solution and I appreciate all your responses.
     
  15. ChapmanF

    ChapmanF Senior Member

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    Point taken ... and it's true I have done all those things, including trying to use A/C during the warm snap last March. The only noticeable effect was that I sat there thinking "hmm, why is that air not colder ... d'oh, take out the grille block, dummy!" I had worried a bit about refrigerant pressure (pretty sure there is a high limit switch, though), but it had not occurred to me to worry about the fans. Maybe I'll try to get some IR temperature readings of the fan motors some time when it's warm with the grille block in.

    -Chap
     
  16. WHCSC

    WHCSC Member

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    So is it the upper grille or lower grille or both?
     
  17. ChapmanF

    ChapmanF Senior Member

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    Well, looking over the thread, it looks like the OP got several responses from different people doing different things that don't all fit equally well in the upper-/lower-grille way of framing the question (since one isn't blocking the grille at all, but does go behind one of the radiators, which a grille block wouldn't).

    That's probably ok if what the OP wanted was to get information, and not just to insist on one preconceived way of framing the question.

    The bird's-eye-view answer seems to be that, especially if you have something like a ScanGauge and can keep an eye on temps, you can do pretty much anything you like using materials at hand, watch your temps, and be ok.

    -Chap
     
  18. joedirte

    joedirte Member

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    vinyl step material fits nicely just in front of radiator.. The inverter coolant radiator will still have air flow then.
     
  19. LEVE

    LEVE Member

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    Do any of you remember, or have seen, the early 1960's Volvos? As a child my parents had a 1960 Volvo. This car had a radiator blind (similar to the Mory Radblind) that was operated via a chain pull. You'd simply pull the chain located under the dash. This would raise or lower the blind in front of the radiator. It was simple and worked well in colder climates. I've always wanted to build something like this powered by a small electric motor.

    On all my vehicles I've made vinyl winter fronts to cover the grill. But now, with two Prius sitting in the garage (a 2002 and a 2005) I've yet to make one for either. I'm still researching this. So, this thread is of great interest.
     
  20. 3prongpaul

    3prongpaul Hybrid Shop Owner, worked on 100's of Prius's

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    Off topic a bit but one feature of the recent Ford Fiesta's is automatic grill blockers.