My AC Conversion Thread

Discussion in 'Technical' started by facelessnumber, Jun 8, 2009.

  1. sierra grabber

    sierra grabber Certifiable

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    Hmmm, both things sound like a relay set could help. there is already a thread on installing the headlight one (fairly convinced to do this myself on the grabber and my truck) im sure doing it for the A\C could be about as easy. just buy a junkyard car relay box and you would have four or five to work with. Lo beam, High beam, A\C, electric fan.... yeah i guess the compressor works OK, just Soo Big :dizzy:....
     
  2. facelessnumber

    facelessnumber Drew Pittman

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    Yeah, it's huge, and it seems even bigger because it's horizontally mounted, (Volvos use this compressor mounted vertically and it doesn't take up so much space) and it's on top, and it's got excessive bracketry...

    As for the relay stuff, yeah, that will be simple. I've got a bunch of relays wired up already. One to power the fan, another to kill power to the fan while the starter is cranking, another for the ignition system... No big deal. But I put a 30a fuse in today though, and so far I've not been able to blow it, so that may be a non issue now.

    One thing that is an issue though... Running 210-215 degrees on the highway and 220-225 in stop-and-start traffic. This is at 90+ degrees on a humid day with the headlights on, stereo up, and AC on full blast. Not dangerous temps, but still probably higher than I want them. Is this typical?

    My current theory on that is the electric fan. I can see on my ammeter the alternator's not quite keeping up at idle with all that stuff turned on, so I would think if the lights are dimming while idling in traffic then the fan's not moving as fast as it could either. The good news is the temp's not running away, it's sustainable, and I'm not likely to hurt anything if I run like this until I score a bigger alternator.

    And the AC performed very well the whole time I was driving around on the interstate, on back roads, and in traffic. And I don't feel like the car's being dragged down significantly in performance either.

    Final receipt count is $270.78. Not too bad I think, for doing a full factory AC install in a car that's never had it. 'Course that figure doesn't include the sweat...
     
  3. sierra grabber

    sierra grabber Certifiable

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    if you go bigger alt, get the late model mustang high output. the after market chebby conversions suck. i have a couple sitting in the garage that only ran a little while before burning out the rear bearing and built in brushes. one is the powermaster brand, the other a summit one. i rebuilt one but am reluctant to put it back on....
     
  4. facelessnumber

    facelessnumber Drew Pittman

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    My only dilemma on the alternator thing is my ammeter. I have found having an ammeter to be invaluable, and I really don't want to have to switch to a voltmeter. If I can get a 90-100 amp alternator I can still use the ammeter, but a 3g alt, (which will probably solve all my problems) will be too much for that. Really even my stock reman alternator is enough to do the job, I just need something that produces a little more punch at idle. Maybe an undersized alternator pulley would do the trick, but I've not been able to find one.
     
  5. facelessnumber

    facelessnumber Drew Pittman

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    Well, I did blow that fuse again today. Only happens with the blower on high, so until I put that on its own circuit I'll just have to not do that.

    220 degrees on the highway today, I really don't like that. I'm pretty sure I want a condenser fan on it, and I plan to upgrade the alternator too, but those shouldn't be a factor on the highway. So the first thing I'm going to do is drain the radiator and then refill it, to ensure I have a 70/30 ratio of antifreeze and water, then add a bottle of WaterWetter and see what happens.

    Still blowing cold though!
     
  6. Joe Dirt

    Joe Dirt BBF life

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    1990 E250 van uses an externally regulated 140 amp alternator.I have one on my maverick (y)
     
  7. facelessnumber

    facelessnumber Drew Pittman

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    Interesting. How does it perform at idle?
     
  8. Joe Dirt

    Joe Dirt BBF life

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    no idea on the amps but 14.5V
     
  9. rayzorsharp

    rayzorsharp I "AM" a Maverick!

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    An alternator will only charge as many amps as needed to keep the battery charged up. A 140 amp alternator would unlikely ever see 140 amp output unless something was severely wrong. If you have a combination of components drawing about 40 amps then that's all the alternator will charge to keep the battery fully charged. So, amps depend on what's being used, and as stated, volts should be "around" 14.5.
    There's nothing wrong with a large amp alternator but it's overkill on a Maverick unless you have lots of goodies drawing lots of juice at once.
     
  10. facelessnumber

    facelessnumber Drew Pittman

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    Well that's kinda the point, really... The stock (60 amp?) alternator is enough, but not at idle. At 1000 RPM the ammeter goes back above zero, but shows negative draw at idle when the AC, fan and headlights are on. I can't do that for terribly long (fast food window?) or eventually the fan will slow to a crawl and my engine temp will go up while my battery drains. My car's got modern headlights, extra brake/tail light bulbs, electric cooling fan, MSD, air conditioning, and that's all before I even turn the stereo on. It's not like weapons grade subwoofers or anything, but I do have an amp.

    I'd just like the alternator to perform better at lower RPMs, really. I think if I can find a smaller alternator pulley than what I have I might be in better shape.
     
  11. facelessnumber

    facelessnumber Drew Pittman

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    Got the blower on its own 30a fuse and a relay now. I can run the blower wide open without concern!


    Update on all that... I drained and flushed the radiator, then filled it with 70/30 water/antifreeze, plus a bottle of WaterWetter. (That stuff's not magic, but it does work as advertised, I'm a believer!) That helped, to a point. Then I hit 225 again after coming off the highway into traffic. It was a really hot day, so that was a good test, but again not like I want it. Then I found out after it cooled I needed to top off the radiator again and burp the upper hose. Now with no air in the system (or not much) it seems to be a lot better. I need another really hot day to be sure.

    Last night I put a 9" pusher fan on the condenser. I mounted it with the motor about even with the bumper so I could minimize how much air it might block when it's off, and I wired it to a relay triggered by the compressor clutch. The theory here is that it will improve AC performance when I need it most - slow speed city driving, and hopefully it will help with engine cooling as well. I haven't driven the car since I did this, but I'll report the results when I do...
     
  12. chirt

    chirt Carlos Hirt

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    nice! now haw about a pic of that condenser fan?:)
     
  13. facelessnumber

    facelessnumber Drew Pittman

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    There ya go... Like everything in this project, it's not pretty but I think it's going to do the job.
     

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  14. chirt

    chirt Carlos Hirt

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    that's cool!:bouncy: and it looks like there is space for another fan.
     
  15. Joe Dirt

    Joe Dirt BBF life

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    may have to go to a mechanical fan and a shroud to keep the temps under control
     

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