Robin C Posted August 16, 2002 Share Posted August 16, 2002 In conjunction with fitting an apollo tank I would like to fit a combined oil temp/oil pressure gauge rather than using the switch Caterham supply. Most of these gauges seem to be mechanical in operation using capilleries. Can anyone advise what I need to do to change the electronic sensors to mechanical ones - or at least identify the threads so I can speak to Demon Thieves etc. Advance appreciation. Robin. Link to comment Share on other sites More sharing options...
Mike Biddle Posted August 16, 2002 Share Posted August 16, 2002 Robin, you don't mention your engine make/variant, so information on threads will not be forthcoming. What I can tell you is that the guages come with the senders, and if you buy from a knowledgeable supplier they will indentify them for you. I doubt demon theives come into this category at least as far as Caterhams are concerned, so go to someone who knows the cars. I have one of these on my VX car, and it's far better than the electronic variety. Link to comment Share on other sites More sharing options...
Mr Locust Posted August 16, 2002 Share Posted August 16, 2002 Try here http://www.lrx.com/forum/messages/4753.html Link to comment Share on other sites More sharing options...
Peter Carmichael Posted August 16, 2002 Share Posted August 16, 2002 How exactly do you measure temperature with a capillary? I have always wondered. The capillary thing has always seemed daft to me which might be because I have never seen it in operation. That said, I have just had two oil pressure senders fail on me. You have identified the problem with the rubbish damping on the standard caterham oil pressure gauge. The problem is with the gauge and not the sender. There are better gauges. The electric sensing thing is at the heart of all datalogging, so is not inherently faulty. Peter Loadsachequestubs Carmichael Link to comment Share on other sites More sharing options...
Mr Locust Posted August 16, 2002 Share Posted August 16, 2002 The system is sealed like a bulb thermometer. A brass (?) bulb in contact with the water contains wax or liquid which expands causing the pressure gauge to rise. Similar idea to the thermostat in the cooling system. This is why the assembly is supplied ready made up with capillary tube etc a fixed length. Link to comment Share on other sites More sharing options...
Mr Locust Posted August 16, 2002 Share Posted August 16, 2002 See http://www.completeautomobilist.com/online/itm00890.htm Link to comment Share on other sites More sharing options...
Mr Locust Posted August 16, 2002 Share Posted August 16, 2002 This in fact appears to be the very puppy http://www.completeautomobilist.com/online/itm00217.htm By the way this was just a quick browse - I have no vested interest in this company! Link to comment Share on other sites More sharing options...
Robin C Posted August 16, 2002 Author Share Posted August 16, 2002 Oops sorry.... The engine in question is the K Series Link to comment Share on other sites More sharing options...
Super_Rich_Bernie Posted August 16, 2002 Share Posted August 16, 2002 Mr Locust - I think its mercury in the sender. The Smiths capillary oil & water temp guages functioned fine on the 200,000mile + 50s car I had until recently, without having been touched. As did the mechanical oil pressure guage (a tube from an oil gallery to the guage) and the mechanically driven rev counter. Nothing inherently wrong with electrical guages, but I suspect the ones fitted to most cars are cheap and nasty. Another bit of trivia - www.completeautomobilist.com belongs to one time F1 entrant Colin Crabbe. Jonathan Link to comment Share on other sites More sharing options...
Mr Locust Posted August 16, 2002 Share Posted August 16, 2002 I stand corrected Jonathan. 😳 Link to comment Share on other sites More sharing options...
Mr Locust Posted August 16, 2002 Share Posted August 16, 2002 Am I right to assume that standard threads may be BSP or BSW? Link to comment Share on other sites More sharing options...
Peter Carmichael Posted August 16, 2002 Share Posted August 16, 2002 The temp thread in the Apollo tank always used to be NPT. All oil pressure fittings on the engine itself are BSP. Rob Walker is entitled to the opinion that there is bugger all difference between the two, but I have had trouble attempting to cross-fit components. Peter Loadsachequestubs Carmichael Link to comment Share on other sites More sharing options...
Mr Locust Posted August 16, 2002 Share Posted August 16, 2002 Seem to remember that the difference is only in the thread form for some sizes. But I may be wrong. Link to comment Share on other sites More sharing options...
Johnty Lyons Posted August 16, 2002 Share Posted August 16, 2002 The SPA Design guages are very accurate and electrical It really is not IMHO a good idea to fit mechanical guages to a Caterham bit like throwing away the Fuel injection and Throttle bodies and refitting a set of Webbers. The adv of the SPA guages is compactness easy wiring configurable warning outputs etc.I have no connection with SPA just a happy chappie. I think Nudger uses these as well. jj N.I. L7C AO. Membership No.3927. Link to comment Share on other sites More sharing options...
Robin C Posted August 16, 2002 Author Share Posted August 16, 2002 Jonty, I have seen the Spa gauges and they do seem impressive - however they are a bit expensive. I was hoping to use say the Racetech gauge from DT which is approx half the price of a Spa. However if converting the senders to mechanical proves too difficult/costly I may have to opt for the Spa which as you say slots straight in. Still a lot of money to pay to avoid 1 extra swith in the dash!!! Thanks to all the other replies. Robin. Link to comment Share on other sites More sharing options...
old captain slow Posted August 17, 2002 Share Posted August 17, 2002 I have just given up on the electric gauge combo on my 1.6K as I seem to go through senders at regular intervals. I recently tried all combinations of gauge, sender, take it to Caterham. Message was there is nothing wrong with the engine and the gauge only gives an indication. However, driving with the reading below 2 bar is just not on psychologically. Checked out all the wiring and couldn't find a problem either. So... Have fitted the Racetech ancient technology dual oil press and temp gauge. Oil pressure is fine at 60 psi dropping to about 50 when red hot after some sustained high speed running. Reading is nice and steady. No fitting probs. You need an adaptor for the engine end obtainable from Redline in Caterham. (Caution as it's got a tapered thread). The oil temp is more tricky to fit as it has to go in the oil line to the Apollo. I haven't sorted that yet so the capillary is tie-wrapped under the bonnet at the moment. (Under bonnet temp at the air inlet = 40C). I intend to fit an oil cooler at the next upgrade and will connect it in then. Minus point - the Racetach gauge is different to the others on the dash. Plus point - the ground clearance is improved as the sender is not hanging down any more and I have a good indicated reading. Fitting time 30 mins tops. C7 CDW Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted August 19, 2002 Share Posted August 19, 2002 A good bet would be to phone Dave Kimberley at Demon Tweeks (and apologise for mispelling their name) and ask him what's needed. He provided me with all the adaptors tp fit my senders and I didn't (and still don't) know whay threads are on them, but they fitted fine. Alex Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now