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CwazyWabbit

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Posts posted by CwazyWabbit

  1. Nick,

    Just a thought, the web site says they heat the lines to over 200f in a couple of mins, you could try putting some fuel line in a pan of boiling water for a while and see what happens to it (200f is 93C). But getting the specs would be better.

    They also show a filter heater on the site, a bit further down the page which looks to be made out of the same wire..... that would suggest your filter wrapping would be fine ..... but just because it looks the same doesn't mean it is, with resistance wire a long length of wire would not get as hot as a short length of the same wire with the same voltage. Have you tried dropping an email to the company?

  2. Mine is now doing the same as yours jad, little under 750rpm cold but 750rpm after a run. :-)

    Out of interest Jad when you get a moment it would be interesting to know the diameter of your crank pulley and the diameter of your alternator pulley (measured at the top of the ribs).

    Sounds like the tacho is right for your pulley combination, but it was under reading on mine and is under reading on reb78's. It's good to know it works as standard on at least some 200tdi's :-)

    From what I have heard there are two different types of 200 tdi crank pulley, I don't know if they are different diameters but they have different locking tools.... maybe you have the older crank pulley (with the slots) and reb78 has the newer one with the threade holes like the 200tdi? that's pure guesswork but may be a plausible reason for the difference.

  3. Just been out for a spin and all looking good :-)

    Indicated RPM's went up to 3800 rpm before I chickened out as the engine sounded to be going as fast I was comfortable with (never rev'd it that much before based on the sound anyway)

    When I got back idle tickover was pretty much 750 rpm.

    I'm happy :-) sorry for all the posts but it helped a lot with the thought process, even though in the end I should have just peeled all the stickers off!! lol. Also working out the theory means I now feel like the guage is properly calibrated and can trust what it is saying.

  4. The adjuster for it is hidden behind a white sticker on the side of the guage, about an inch bach from the front edge and at the bottom (behind where it says vdo)

    Mine now indicates 750rpm with 196hz and 4000rpm with 1040hz

    Have fun .... unfortunately I had to take mine apart to find it (stupid moment doh) SO I shall be trying to put mine back together nicely now :-S

  5. Just playing with a few numbers and a multiplier of 3 would work best with my guage....

    6000rpm would give 1800hz

    5000rpm would give 1500hz

    4000rpm would give 1200hz

    3000rpm would give 900hz

    2000rpm would give 600hz

    1000rpm would give 300hz

    750rpm would give 225hz

    which if you compare with the actuals results from the test I did

    6000 rpm = 1726hz

    5000 rpm = 1435hz

    4000 rpm = 1170hz

    3000 rpm = 870hz

    2000 rpm = 570hz

    1000 rpm = 260hz

    750 rpm = 228hz

    500 rpm = 163hz

    250 rpm = 106hz

    They are really pretty close (trust me to have chosen 1000rpm for my other post which seems a bit of an anomoly)

    That would mean I need a 53mm pulley on the alternator :-s ..... what's interesting is the outside lip on the 49mm pulley is 53mmm ..... I wonder if someone made a mistake somewhere along the lines? or maybe they just stuck it halfway between pulley sizes so it was about right?

    (I really hope my posts all come out in order when the moderator reads them)

  6. So based on my guage, and poor maths....

    Actual RPM Expected frequency on W terminal Indicated RPM

    750 195hz 600 rpm ish

    1000 260hz 1000 rpm

    2000 520hz 1800 rpm

    3000 780hz just over 2600 rpm

    4000 1040hz just over 3500 rpm

    For a list price of £140 odd punds you would expect a bit more accuracy than that I would have thought :-(

    So it's not a particularly accurate guage but appears to be designed for the 160mm crank pulley with the 61mm alternator pulley ..... I wonder if anyone does a digital tacho???? (I'm sure the mrs doesn't really want that new cooker....)

    reb78, hope these figures help with yours.... they seem to marry up with your experience of it.

    PS I'm currently moderated so my responses take a while to show up ... hopefully they don't get too out of step.

  7. Sorry for all the replies

    Looks like there are two different alternator pulley sizes available for the 300tdi :- (from http://forums.lr4x4.com/index.php?showtopic=7336)

    49mm From VIN TA969103------Pt No STC3202

    61mm To VIN MA969102----------Pt No STC1796

    Mine has the 61mm pulley which would mean it will read about 20% slower than the 49mm

    The crank pulley is 160mm (measured from a spare engine, hope there is only one size) so the relative step ups of the two pulleys are (I hope my maths is correct :-S)

    160/61 = 2.6

    160/49 = 3.25

    Now representing RPM in hz (cycles per second) choose an arbitary engine speed of 1000rpm

    1000rpm/60 = 16.66 hz

    Multiply by 2.6 (for 61mm) to give alternator speed

    16.66 hz * 2.6 = 43.33 hz

    Multiply by 3.25 (for 49mm) to give alternator speed

    16.66 hz * 3.25 = 54.15 hz

    From my measurements in previous post (assuming it got approved)

    to show 1000rpm on an AMR1912 we need 260hz at the W terminal.

    There is obviously some multiplier affect within the alternator, if we knew the correct amount we could work out which alternator pulley (if any) is the correct one for the AMR1912 to read the correct RPM.

    Effective multiplier of alternator for 61mm pulley to be correct would be...

    260hz/43.33hz = 6

    Effective multiplier of alternator for 49mm pulley to be correct would be...

    260hz/51.45hz = 4.8

    The multiplying effect in an alternator is a product of the number of poles it has, basically a 12 pole alternator has a multiplier of 6 and a 10 has a multiplier of 5. from wikipedia (http://en.wikipedia.org/wiki/Alternator)

    So the question boils down to is the alternator on my 300 tdi a 12 pole alternator?

    The general consensus of the web is that most alternators are 12 pole so that would mean after all that the AMR1912 will work fine on my 300 tdi defender..... I better go and wire it up properly this evening :-)

    Please check my working out, I hope to be corrected if I am wrong.... thanks and sorry for my ramblings.

  8. Hello all,

    (This is my first post on here so go easy on me)

    I bought one of these and am only just getting around to fitting it (always seems to be something else I'm 'supposed' to be doing). Anyway I remembered this thread to I hooked it up temporarily first and saw the idle speed was showing a little over 500rpm. Now from what I've read the idle speed should be around 750rpm, so do I believe the guage?

    I've noticed there is no adjustment on the guage (you can't even take it apart, unless you want to damage the surround) but I did notice a sticker saying 12V/1800HZ, does anyone with an accurate guage also have a sticker indicating HZ?

    I wanted to see what the 1800hz corresponded to so I set up a test with a frequency generator and an oscilloscope and took some readings for various indicated rpms.

    250 rpm = 106hz

    500 rpm = 163hz

    750 rpm = 228hz

    1000 rpm = 260hz

    2000 rpm = 570hz

    3000 rpm = 870hz

    4000 rpm = 1170hz

    5000 rpm = 1435hz

    6000 rpm = 1726hz

    So it looks like the 1800HZ is supposed to represent full needle deflection.

    Does anyone know what frequency the alternator should produce for a given engine rpm?

    Sorry for all the questions on what is now an old thread (makes mental note to get off backside quicker in future)

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