rozentas Posted July 13, 2019 Report Share Posted July 13, 2019 When I start my car I get the noise in the attached file. Would be grateful if anyone can advise what it might be. I have disconnected the alternator to make sure its not the water pump..........it is not. I took of each spark plug in turn......makes no difference to the noise. Regards, Steve Voice_002.m4a Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 Whats the history of this, did it suddenly start doing it while driving or just on start up and did it get louder and louder? Have you done any jobs in the engine area recently, how many miles do you think its done and I take it the oil pressure warning light works but stays off when running? Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 Johny, thanks for responding. Suddenly started yesterday while driving sounded like fan brushing the radiator at first then got louder so realised it was not that. Drove ten miles home slowly and the noise was constant. Coasted downhill when I could. Starting got harder each time until 200 yds from home would not start at all. Lifted hood when I got home, coolant was boiling over, oil was gone........no leaks it had just burned up. Filled coolant and oil this morning and the noise you hear is what I heard on first start up when cold. Engine starts fine each time but the noise is ever present I have replaced the fuse board last week as the old one was badly corroded and the gauges did not work. The oil pressure light does not come on at all, at ignition or while running. Steve . Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 uuufff the oil light should come on with the ignition is turned on to prove the bulb and circuit. The pressure switch could be stuck open or the wiring faulty but either way this needs fixing first and to be honest you shouldnt have driven it without it working correctly..... Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 Can you tell me where the pressure switch is and I will check the circuit. Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 well most likely its the bulb which is obviously in the back of the speedo so a bit of manual dexterity is needed to access it. Otherwise the switch is a cylindrical item mounted on the LH side of the engine block with a wire going to it which if disconnected and put to earth should light up the oil light when the ignition is on. I forgot to ask if you have an oil pressure gauge fitted? Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 13, 2019 Report Share Posted July 13, 2019 unless youre lucky that sounds a bit terminal but not big endish. i wonder if the oil pump drive has failed ???? Pete Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 Johny, I do not have an oil pressure gauge. Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 Pete, is there a way to check the oil pump drive without taking the sump off? Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 Johny, the brake light does not come on when the ignition is on and the handbrake off, so I guess my problem could be at the oil pressure switch where there is no ground. Does that make sense to you? Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 brake light? Turn the ignition on, disconnect the wire to the oil pressure switch and touch it down to a clean area of the engine block and check the oil pressure light comes on... Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 yes the oil pressure light comes on if i touch the engine block Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 I found the following on another site The oil light power is supplied via the brake warning light circuit. Because you have no brake light either, you circuit is open at the brake lamp. Check that bulb. If the bulb tests ok, check the wires. The circuit gets it's 12v from the ignition switch via a white wire at the ign switch side of the top fuse. There is a purple wire that continues from the brake bulb to the brake warning switch at the master cylinder and also to the oil light. How the circuit works is that with the ignition on and the engine off, the circuit finds ground at the closed oil pressure switch, which lights both the brake warning light, and the oil light. When the engine starts and oil pressure builds, the oil pressure switch opens, and the circuit loses ground and the lights go out (provided the handbrake is off. With the hand brake on the brake light still finds ground via the handbrake switch). In the event of a brake failure, the brake light will find ground through the brake warning switch and the brake light will light, but th oil light will not. In the event of loss of oil pressure, the oil light and the brake light will both come on (this is the same condition as ign on engine off) Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 13, 2019 Report Share Posted July 13, 2019 you can get some idea if the pump is operable remove the dizzy base pedestal and youwill see the drive gear meshed with the camshaft remove the gear the drive shaft is then exposed and can be drive by a elelctric drill with a means of adapting how it drives the shaft end you need a pressure gauge plumbed into the oil switch union to see any pressure build up if the pumps working and going the right way, its easy to test and find youre running backwards BUT i would get a gauge plumbed in asap and see if you are getting any pressure before you start stripping bits off the sump can be removed in car with a fiddle........... more on that if needed do the easy cheap first. you are correct the PDWA valve switch is linked to the oil pressure warning on a 1500 Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 Thanks, question re oil pressure sensor. Mine is screwed into the engine block only about 5 mm. The rest of the thread is outside the engine block so I guess I am not getting a good ground because there is no part of the sensor casing touching the engine block. Should the sensor screw all the way into the engine block so the outer casing of the sensor is touching the engine block? Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 13, 2019 Report Share Posted July 13, 2019 no its a taper thread you can plumb a gauge direct into where the switch is or most fit a tee peice and keep gauge and low pressure switch working the switches are not going to last a lifetime and can fail , none of this will sort your noise for you that rattle sounds like no oil and crank bearings are heading for trouble , its not a big end knock but its nasty !!! Pete Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 Hi Steve, it doesnt really matter how the oil pressure switch is wired up, if its light comes on when the wire is earthed there is a problem with the switch and it must be changed. Once you do this and the light comes on with the ignition you have two possible next steps: investigate whether the oil pump is being driven or just start the engine and see if the oil light goes out. As youve already driven the car like this I think the second option is probably ok for a short while and, as Pete says, if you can do it with a pressure gauge even better. From there we'll have a think about where to go next.... Link to comment Share on other sites More sharing options...
Nick Jones Posted July 13, 2019 Report Share Posted July 13, 2019 With that noise I reckon it's a bit late to be worrying about oil pressure......... Sounds big-endy to me, or maybe broken piston. Certainly wouldn't be driving the car, not sure I'd even be running it. Nick Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 If I took the spark plugs off in turn and it was a piston problem I guess the noise would stop when I removed the cylinder with the dodgy piston? Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 yes youre probably right but it could be a dropped valve or broken piston so it would be nice to know if theres oil pressure and then do a compression check to get a better idea. Also in the recording I heard one slight mis knock which could have been down to sound quality or something that doesnt fit in with big end failure.... Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 Can I run the engine without the rocker cover on to see if the source of the noise becomes clearer? Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 not necessarily Steve as the pistons are still going up and down Link to comment Share on other sites More sharing options...
rozentas Posted July 13, 2019 Author Report Share Posted July 13, 2019 How do I do a compression test? Link to comment Share on other sites More sharing options...
johny Posted July 13, 2019 Report Share Posted July 13, 2019 yes you can run a while without the cover although after a while oil might start collecting in the area. You need a compression tester, a pressure gauge that screws into the spark plug hole although with just a finger over the holes youll get an idea if theyre all the same.... Link to comment Share on other sites More sharing options...
Pete Lewis Posted July 14, 2019 Report Share Posted July 14, 2019 If the breather is left open by removing the rocker cover it probably wont run I fear you are trying to tickle a an elephant with a feather theres a serious problem with your engine , it wont be solved by dreaming up around simple hopes , rattles like you have will in the end need a strip down , if its had some oil supply problem then with a 1500 its a good chance the noise eminates from a terminal failure in the major mechanicals not any simple bolt on ancillaries Pete Link to comment Share on other sites More sharing options...
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