daverclasper Posted January 26, 2020 Report Share Posted January 26, 2020 (edited) Hi. Just in case the oil pressure gauge plastic tube fails, would it be worth fitting a buzzer, inline with the pressure warning light?. Cheers, Dave Edited January 26, 2020 by daverclasper Link to comment Share on other sites More sharing options...
Colin Lindsay Posted January 26, 2020 Report Share Posted January 26, 2020 Wouldn't do any harm, as, even if you do have one fitted, you can't always be looking at the gauge. Buzzers are cheap these days and should be simple to connect up. (The pipe for the gauge intended for my Herald is metal, so should last slightly longer than plastic. Now I'll have to inspect the GT6 pipe as it's been on there twenty years.) Link to comment Share on other sites More sharing options...
Pete Lewis Posted January 26, 2020 Report Share Posted January 26, 2020 audible is always best , you dont see gauge drops or warning lights till you hear the engine noise and then start looking lots of simple buzzers on e bay for flashers etc all will work on the LP switch Pete Link to comment Share on other sites More sharing options...
Clive Posted January 26, 2020 Report Share Posted January 26, 2020 You can buy a kit that consistes of a higher pressure switch (up to about 25lb, a bit high for many triumphs!) but importantly is supplied with a much larger and brighter lamp, that would be difficult to miss. Even a buzzer would need to be pretty loud in a triumph, especially if tucked away. I have a kit somewhere I really ought to fit to my Spitfire. I don't bother with a gauge as they become distracting, better off watching teh road (or track) Link to comment Share on other sites More sharing options...
dougbgt6 Posted January 26, 2020 Report Share Posted January 26, 2020 Dave, Great idea. I like it! I’ve got a buzzer for the indicators, but I guess a continuous tone with a different frequency wouldn’t be confusing. Also if it sounded on the “death rattle” at start up it tells you it’s working. Doug Link to comment Share on other sites More sharing options...
Pete Lewis Posted January 27, 2020 Report Share Posted January 27, 2020 used to link a anti theft ign earth ?? to the LP switch with a overide switch so when pressure built the engine cuts out Link to comment Share on other sites More sharing options...
daverclasper Posted February 8, 2020 Author Report Share Posted February 8, 2020 Thanks for the response's. Well, I assumed, (never a good thing) that a piggy back connector, off the pressure switch would give me a live for the buzzer, doesn't seem to be the case. I guess the warning light is a bit more involved than that?. Any ideas where best to wire it in please (pos/neg), ideally without pulling the dash?. Have looked at wiring diagram, though electrics not my strong point. Cheers, Dave Link to comment Share on other sites More sharing options...
johny Posted February 8, 2020 Report Share Posted February 8, 2020 The live goes to warning light and then to the pressure switch so that when pressure drops the switch earths through the engine and current flows through the bulb. A buzzer could just be connected either side of the warning light all in the dash ie live from ignition switch to one side and back to the pressure switch wire on the other. Then on low pressure current will flow through the bulb and, in parallel, the buzzer down to earth to make the circuit.... Link to comment Share on other sites More sharing options...
daverclasper Posted February 8, 2020 Author Report Share Posted February 8, 2020 23 minutes ago, johny said: A buzzer could just be connected either side of the warning light all in the dash Thanks Johny. Does this mean, one side, OR the other. eg, can I wire the single live from the buzzer, into the live for the bulb at the ignition switch?. I've still only got a pretty basic understanding of electrics, despite lot's of reading up. Cheers, Dave Link to comment Share on other sites More sharing options...
johny Posted February 8, 2020 Report Share Posted February 8, 2020 sorry not very clear, buzzer should be connected BOTH sides of warning light. This means the buzzer live wire connected anywhere between the ignition switch and the bulb and the buzzer return wire anywhere between the bulb and pressure switch. The electricity will just split and the right amount will go to both the bulb and the buzzer when the pressure switch detects low pressure and connects to earth. Link to comment Share on other sites More sharing options...
johny Posted February 8, 2020 Report Share Posted February 8, 2020 When I say ignition switch the supply to the oil pressure light is actually coming from a fuse which is supplied from the ignition switch when turned on so of course you want to use this fused supply for the buzzer not directly from the igntion switch.... Link to comment Share on other sites More sharing options...
daverclasper Posted February 8, 2020 Author Report Share Posted February 8, 2020 12 minutes ago, johny said: the buzzer return wire anywhere between the bulb and pressure switch Thanks Johny. The buzzer has two wires, Pos and earth. Are you calling the earth, the return?, as earths are sort of this?. Link to comment Share on other sites More sharing options...
johny Posted February 8, 2020 Report Share Posted February 8, 2020 Yes the 'earth' is the return as in this case it wont be connected directly to earth (vehicle chassis) cos it would then sound continuously whereas we want it to be controlled by the pressure switch.... As an aside normally wiring goes: supply, switch, light and then earth. This is more reliable but cars because of technical/cost constraints dont always follow this design and the weakness, as in the oil light circuit, is that if the return wire is damaged and shorts to earth before the pressure switch it will give a false alarm. Link to comment Share on other sites More sharing options...
daverclasper Posted February 8, 2020 Author Report Share Posted February 8, 2020 Thanks. I think I will piggyback off the fuse box and the switch, as easy access and don't have to hack into the harness. Does this sound ok?. Link to comment Share on other sites More sharing options...
johny Posted February 8, 2020 Report Share Posted February 8, 2020 Youre right, best to leave the original wiring alone as much as possible. Ive just noticed that on my car the supply to the oil light doesnt come through the fuse but directly from the ignition switch (white wires) and you'd better stick to this. To do it properly you should connect to this supply but use an inline fuse before wiring to the buzzer.... Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 8, 2020 Report Share Posted February 8, 2020 audibles are better than visuals but after 40 years of no problems its a bit late to get paranoid about these concerns drive and smile , or you could connect in a low brake fluid warning to improve the blood pressure ha ! have faith in your car pete Link to comment Share on other sites More sharing options...
johny Posted February 8, 2020 Report Share Posted February 8, 2020 hey wheres the fun in not fiddling and installing 'upgrades'😍 Link to comment Share on other sites More sharing options...
NonMember Posted February 8, 2020 Report Share Posted February 8, 2020 2 hours ago, johny said: As an aside normally wiring goes: supply, switch, light and then earth. This is more reliable but Actually, there's no difference in reliability. The electricity doesn't care whether it flows through the switch first (and, in fact, it flows the opposite way from how we conventionally refer to it anyway). The reason for switching the "live" side on, say, house wiring is purely safety. Our mains system is designed so that "live" is a long way from "earth" and "neutral" is close to "earth". When you change your light bulb, you are "earth" and the bulb socket is "neutral" - as long as you've turned it off! This is not a concern on a low voltage system like a car. Having a switch that isolates the supply helps when you may be exposing wires (although you've disconnected the battery for that, haven't you?) but there are cases where a ground-side switch makes the result of an exposed wire less trouble - it merely turns something on instead of letting the smoke out. When you start switching things electronically, it turns out usually much more convenient to switch the -ve (conventionally earth) side. The same is true if you have a switch fitted into a nicely earthed bit of metal, like an engine block or a steering column. That tends to be the consideration that wins out. Link to comment Share on other sites More sharing options...
johny Posted February 8, 2020 Report Share Posted February 8, 2020 I meant reliable in that things dont operate if you get an earth fault. A good example is the car interior light which if you have an earth fault in any of the wiring from the light itself (quite a lot of cabling) switches the light on and as its not dependant on the ignition switch can flatten your battery if it happens without you noticing.... Link to comment Share on other sites More sharing options...
daverclasper Posted February 8, 2020 Author Report Share Posted February 8, 2020 (edited) Your right Pete. Got faith in the car, (and is nigh on original, even the lucas fuse box has not given trouble) not sure about that old plastic tube (gauge on the car when I got it) carrying, I assume, a lot of pressure, a weak point?. Maybe I should just blank it off?. For some reason, brakes, are less worrying to me (mine are maintained, by the way). If the engine destroys, that's the end of game for me prob. (no facilities) and ltd cash. Edited February 8, 2020 by daverclasper Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 9, 2020 Report Share Posted February 9, 2020 plastic tube is used by many even as OE dont worry about it , less likely to fail than a metal tube think we were the first to use nylon air pipes on trucks air brakes back in the 70s and we all thought WHAT , now used by all so plastic stops 44tons ok pete Link to comment Share on other sites More sharing options...
JohnD Posted February 9, 2020 Report Share Posted February 9, 2020 If you are really worried about such a failure, then fit an indicator light in parallel with the sensor. Te insie of a car is a noisy place, where a light will not be missed. A really big one, something like this: https://www.arc-components.com/0-570-00-round-surface-mount-direction-indicator-lamp-1291.html 1 Link to comment Share on other sites More sharing options...
Anglefire Posted February 9, 2020 Report Share Posted February 9, 2020 I've seen plenty of them inside Rally cars John! Normally just flickering when at idle - Set at a pretty high pressure so if it comes one when its been driven hard it **might** save the engine. Friend of mine built a 2ltr Pinto to go in his Mexico - running either 48 or 50 webbers - so did high teens on a good day and middle singles on an event (different times!) Suffice to say he had a catastrophic failure on one event (he had lifted (reed removed!) the rev limiter as he was being caught - and missed a gear. He never did find all the bits of the engine - but the rods had twisted through 90deg and the dipstick came out with half the block attached. Not that an oil pressure light would have helped much 1 Link to comment Share on other sites More sharing options...
poppyman Posted February 9, 2020 Report Share Posted February 9, 2020 I had a pinto that did that Mark, Happy memories....... I had my pinto (1.6) in an Anglia that i used to rally. Tony. 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted February 9, 2020 Report Share Posted February 9, 2020 upgrade to one of these maybe !!! Link to comment Share on other sites More sharing options...
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