youngengineer Posted November 22, 2019 Author Share Posted November 22, 2019 Bloody britpart. 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 22, 2019 Author Share Posted November 22, 2019 Does anyone know if the oil light staying on is due to no output from alt? Quote Link to comment Share on other sites More sharing options...
western Posted November 22, 2019 Share Posted November 22, 2019 Oil light should be off once the oil pressure is built up, alternator shouldn't have any affect on it, If oil light stays on with engine running it could be a duff pressure switch or the wire is chafed & earthing out on the engine. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted November 22, 2019 Share Posted November 22, 2019 Is the charge light turning on with the ignition? If so, disconnect the charge light wire from the alternator. It should then go out. This will prove if the wiring is correct. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted November 22, 2019 Share Posted November 22, 2019 The oil light circuit is very simple. Switched power to the light. Other side of light ot the oil pressure switch. The switch grounds on low oil pressure. Disconnect the wire from the switch and the light should turn off. If not, there is a wiring issue. If it does turn off, either the switch is bad or the oil pressure is low. 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 22, 2019 Author Share Posted November 22, 2019 44 minutes ago, Red90 said: Is the charge light turning on with the ignition? If so, disconnect the charge light wire from the alternator. It should then go out. This will prove if the wiring is correct. Yes I've tested the charging circuit. It goes off when disconnected from alt. Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 22, 2019 Author Share Posted November 22, 2019 40 minutes ago, Red90 said: The oil light circuit is very simple. Switched power to the light. Other side of light ot the oil pressure switch. The switch grounds on low oil pressure. Disconnect the wire from the switch and the light should turn off. If not, there is a wiring issue. If it does turn off, either the switch is bad or the oil pressure is low. It certainly turns off when the wire is pulled off the sensor so as you say. Either the sensor is faulty or oil pressure is low. Since the light does not flicker in the slightest which would suggest low pressure it seems unlikely that there is no pressure at all. Car has not been started in two weeks so I would assume that the sensor has seized if there are moving parts? Other then that, two weeks ago it was working fine. I've never seen the oil light come on when running unless idle was extremely low which it would then start to flicker Quote Link to comment Share on other sites More sharing options...
western Posted November 22, 2019 Share Posted November 22, 2019 Oil pressure will only go out if the engine is running, Engine off but ignition on you should have glowplug light [amber] for around 6 to 8 secs, oil light [red] charge light [red] these 2 red lights only go out when engine is started & running. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted November 22, 2019 Share Posted November 22, 2019 Sounds like two unrelated faults then. Just a coincidence. 1 Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 23, 2019 Author Share Posted November 23, 2019 Ok so just an update. I took the car out today for a spin and noticed the alternator light turned off, looked at the voltmeter and I was on 14.2V. all good it thought. I stopped and restarted the engine and the light was back on again.. I revved the engine up to around 3k and it went off once more and volt back upto 14. Looks like the alternator needs on hell of a rev to get it going. Hmm. Not really very reassuring. On the oil light problem. I removed the sensor from the filter housing and cranked the engine. A fountain of high pressure oil came rushing out so looks like there's plenty of pressure. 1 Quote Link to comment Share on other sites More sharing options...
Ex Member Posted November 23, 2019 Share Posted November 23, 2019 Return the alternator. Quote Link to comment Share on other sites More sharing options...
western Posted November 23, 2019 Share Posted November 23, 2019 I would be sending that alt back. 1 Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted November 23, 2019 Share Posted November 23, 2019 Mine needs 1000 rpm to get the alternator going. The Mrs. on the other hand is impossible to get going these days 😉 Mo Quote Link to comment Share on other sites More sharing options...
western Posted November 23, 2019 Share Posted November 23, 2019 3 hours ago, youngengineer said: Ok so just an update. I took the car out today for a spin and noticed the alternator light turned off, looked at the voltmeter and I was on 14.2V. all good it thought. I stopped and restarted the engine and the light was back on again.. I revved the engine up to around 3k and it went off once more and volt back upto 14. Looks like the alternator needs on hell of a rev to get it going. Hmm. Not really very reassuring. On the oil light problem. I removed the sensor from the filter housing and cranked the engine. A fountain of high pressure oil came rushing out so looks like there's plenty of pressure. What size pulley have you got on this alternator, is it the pulley from the original unit ? Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 24, 2019 Author Share Posted November 24, 2019 (edited) 15 hours ago, western said: What size pulley have you got on this alternator, is it the pulley from the original unit ? Its the pulley it came with. I've had a look today and I would say it needs 2000K to get it going. Once its going its going strong. I can turn everything on and at idle it will maintain 14V. Maybe I need a larger load on the exciter circuit? I believe the bulb is 1.4 to 2W Edited November 24, 2019 by youngengineer Quote Link to comment Share on other sites More sharing options...
western Posted November 24, 2019 Share Posted November 24, 2019 Is the pulley on this new alternator the same diameter as the removed alternator? Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 24, 2019 Author Share Posted November 24, 2019 (edited) 2 hours ago, western said: Is the pulley on this new alternator the same diameter as the removed alternator? Looks about the same. I have another theory though. What if the ground to the oil pressure light and alternator light has high resistance? The bonnet has been off for two weeks so all the connectors would have been rained on almost daily. Edited November 24, 2019 by youngengineer Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 24, 2019 Author Share Posted November 24, 2019 (edited) Hmmm, I've just tested the volt to the alternator light and it's only 10.4 with the bulb on when battery is showing 12.6.. since I would assume that the live feed for alternator light and oil light is the same could this problem be connected? Edited November 24, 2019 by youngengineer Quote Link to comment Share on other sites More sharing options...
western Posted November 24, 2019 Share Posted November 24, 2019 Oil press switch earths via the engine block, so having bonet off won't make any difference, Still reckon that new alternator s duff. Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 24, 2019 Author Share Posted November 24, 2019 (edited) Ok thanks. On a sidenote I've remove my oil pressure sender and put a multimeter to it. I'm seeing almost no resistance when at atmospheric pressure and with an air supply at 80psi I'm seeing 14K ohm.. Hmm, do I really then have low oil pressure then? This is concerning. Edited November 24, 2019 by youngengineer 1 Quote Link to comment Share on other sites More sharing options...
western Posted November 24, 2019 Share Posted November 24, 2019 only way to find out what the oil pressure is by fitting a gauge, either a mechanical one or a electric one. Quote Link to comment Share on other sites More sharing options...
youngengineer Posted November 24, 2019 Author Share Posted November 24, 2019 Well I made a little test jig to see if the light would go out when 120psi was applied to the sender it it did not! Even poking the internals which a spring could be felt actuating and bottoming out it did not extinguish the light.. good news. Looks like the sender is dead. 1 Quote Link to comment Share on other sites More sharing options...
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