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Re: loss of power and poping

To: td214 <td214@cam.ac.uk>
Subject: Re: loss of power and poping
From: Richard B Gosling <Gosling_Richard_B@perkins.com>
Date: 14 Jul 2000 05:56:44 -0500
Tim,

If you are looking for someone who knows how to tune SUs, the guy in the garage
 round the corner from me did a great job sorting mine out for my MOT a couple
 of weeks ago - CO limit for the test is 4.5%, design specs say 3.5 +- 0.5%,
 and he got it to 2.88% - HCs were down to 388 ppm (test limit is 1500 ppm).
 It does mean a 15-minute trip along the A428 into the wilds of the
 Cambridgeshire backwoods!

For more serious work, last year my emissions were off the scale, and I took
 Daffy to a tuning specialist in Peterborough (just round the corner from where
 I work).  They ended up pulling the carbs to pieces and re-building (with all
 the same components, as far as I know), but it made an amazing difference, and
 for a lot less than the cost of reconditioned exchange carbs - fuel
 consumption improved by 1/3 immediately as well!  Sorry, I don't know of
 anyone in Cambridge I can recommend!

Standard engine oil should be fine in the carbs, it is recommended in lots of
 handbooks.  I do use proper carb damper oil, but mainly because I pursuaded
 TRGB to give me a bottle as compensation for something they had screwed up on
 (sent me the wrong part, so I had to drive over there to get them to change
 it, I think!).

As for the temperature thing, I guess the easiest place to stick in a
 thermometer would simply be the coolant cap.  Although, by the time you have
 let the pressure escape enough to pull the cap off completely, you may already
 have lost several degrees, so the reading will not be totally accurate.  Not
 sure what the reading should be anyway - I guess it should be a few degrees
 above the thermostat operating temperature - whatever that is.  Might be on
 the 'stat packaging - didn't you just replace the 'stat?  Bet you haven't
 still got the box!  Anyway, someone out there is bound to know what
 temperature the 'stat is supposed to operate at.

It may be worth simply replacing your temperature transmitter - TRGB have it
 listed at 5.60 (+VAT), at that price it is a cheap-ish and easy way to rule
 that out as a cause, if your voltage regulator seems to be OK.  Certainly is
 cheaper than replacing the gauge (33.95 +VAT).

Good luck, hope you sort it out, and if you want more details on either of the
 places I suggested for tuning let me know.

Richard and Daffy

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