Michel Higuet Posted September 24, 2023 Report Share Posted September 24, 2023 Everything was fine with this engine until yesterday, starting from the start of a little ride test, an intermittent noise while driving, nothing when stopped but today same thing and with car stopped I can play with the accelerator and the noise appears from times to times. the noise is loud and sounds like something is seized and running without oil, high-pitched and metallic. Like a water pump bearing. The noise "seemed" to come from under the valve cover but nothing abnormal at first glance. I removed the alternator belt but no play on the water pump or alternator. In the front housing with the timing chain? How to pinpoint the sound? Quote Link to post Share on other sites
trchris Posted September 24, 2023 Report Share Posted September 24, 2023 Hi Michel Did you run the engine with the alternator belt off ? The best way to pin point a noise is use a long screw driver place the blade on certain parts of the engine you wish to listen to and the handle to your ear you should be able to pin point the source of the noise this way Chris Quote Link to post Share on other sites
Michel Higuet Posted September 24, 2023 Author Report Share Posted September 24, 2023 16 minutes ago, trchris said: Hi Michel Did you run the engine with the alternator belt off ? The best way to pin point a noise is use a long screw driver place the blade on certain parts of the engine you wish to listen to and the handle to your ear you should be able to pin point the source of the noise this way Chris I try the long screw driver but didn't pinpoint anything, the sound is not constant, I came to the same idea this afternoon, to close the valve cover and to run quick round the corner. Thanks Quote Link to post Share on other sites
RogerH Posted September 24, 2023 Report Share Posted September 24, 2023 Hi Michel, could it be a dry rocker arm bush. Slacken each rocker arm and rotate it - any stiffness.!! Roger Quote Link to post Share on other sites
Z320 Posted September 24, 2023 Report Share Posted September 24, 2023 Hi Michel, did you do what Chris asked, to run the engine without belt? I see a standard washer under the nut of your water pump pulley? It could be punched and then your pulley will be slack. Ciao, Marco Quote Link to post Share on other sites
BlueTR3A-5EKT Posted September 24, 2023 Report Share Posted September 24, 2023 (edited) +1for loose water pump pulley check crank pulley and alternator pulley also check alternator is secure Beyond that it could be a broken timing chain tensioner. Edited September 24, 2023 by BlueTR3A-5EKT Quote Link to post Share on other sites
Z320 Posted September 24, 2023 Report Share Posted September 24, 2023 (edited) The construction need a SOLID washer under the nut, not a standard one. And even with that the construction is poor. I explained that in another post. BTW in IMPO most failed water pump bearings are only not tight nuts. Repaired with a new pump because it comes with a solid washer and the nut tighted by the swap. Edited September 24, 2023 by Z320 Quote Link to post Share on other sites
Deggers Posted September 24, 2023 Report Share Posted September 24, 2023 3 hours ago, Michel Higuet said: . . . the noise is loud and sounds like something is seized and running without oil, high-pitched and metallic. Similar to this, Michael? Quote Link to post Share on other sites
Michel Higuet Posted September 25, 2023 Author Report Share Posted September 25, 2023 (edited) Hi everybody, This morning I removed the rocker pedestals, check everything, adjust valves clearance ( by the way for Piper cams .014" = .30mm and 016" = .35mm a curious conversion no? ) Made a quick test run but at the start I could already ear the problem was still there ( without the fan belt of course ). Difficult to pinpoint the origin of the sound. The sound in the voice file is not very good but I the beginning the "metallic coughs" appears and later disappears. Next opening the front carter I suppose... Voice 003_sd.m4a Edited September 25, 2023 by Michel Higuet Quote Link to post Share on other sites
RobG Posted September 25, 2023 Report Share Posted September 25, 2023 Michel, My money on timing chain scraping timing cover. Good job spotted now and not later. RobG Quote Link to post Share on other sites
Andy Moltu Posted September 25, 2023 Report Share Posted September 25, 2023 Timing chain tensioner failed. Cam gear worked loose? If to the rear the bell housing cover plate catching on flywheel? Quote Link to post Share on other sites
gloide69 Posted September 25, 2023 Report Share Posted September 25, 2023 Could it be the distributer? Quote Link to post Share on other sites
Z320 Posted September 25, 2023 Report Share Posted September 25, 2023 (edited) Chain and chain tensior you can check from outside Edited September 28, 2023 by Z320 Quote Link to post Share on other sites
Michel Higuet Posted September 25, 2023 Author Report Share Posted September 25, 2023 I didn't believe in the tension chain but why not believe in a miracle, No miracle in fact... The sound seems coming from the block motor and maybe "maybe" ( just an impression, nothing sure ) more from inlet and exhaust side... The sound come and go, when going smooth revolutions, oil pressure always round the 70 l/s. A little play between woodruff key and hub pulley but nothing new here. A head gasket would give a constant sound, clacks and you need overhitting and bad cooling to ruin a head gasket, idem pierced piston, Nice colour on the 4 sparks. Removing housing cover plate finally not a terrible job... consolation, consolation... Nobody has a Bat man as friend with oversized ears? Quote Link to post Share on other sites
Z320 Posted September 25, 2023 Report Share Posted September 25, 2023 Both valve springs broken on one valve (only one you will not hear)? Quote Link to post Share on other sites
RobG Posted September 25, 2023 Report Share Posted September 25, 2023 Could you drain off a little oil, say half pint to see if any swarf in it, what about camshaft bearings, they would sound from inside motor block. Know any friends (doctors) who have a stethoscope you could borrow. RobG Quote Link to post Share on other sites
rcreweread Posted September 25, 2023 Report Share Posted September 25, 2023 7 minutes ago, RobG said: Could you drain off a little oil, say half pint to see if any swarf in it, what about camshaft bearings, they would sound from inside motor block. Know any friends (doctors) who have a stethoscope you could borrow. RobG You don't need a doctor friend - get one of these: https://www.ebay.co.uk/itm/325824144735?hash=item4bdca1e55f:g:6kkAAOSw3ktlDt5M&amdata=enc%3AAQAIAAAAwG8XhydkCtsd0hoe3lZHq3VTzwcylA%2FxNCLTfZrcMH%2Bn Not expensive and always useful Cheers Rich Quote Link to post Share on other sites
Michel Higuet Posted September 25, 2023 Author Report Share Posted September 25, 2023 (edited) 1 hour ago, rcreweread said: You don't need a doctor friend - get one of these: https://www.ebay.co.uk/itm/325824144735?hash=item4bdca1e55f:g:6kkAAOSw3ktlDt5M&amdata=enc%3AAQAIAAAAwG8XhydkCtsd0hoe3lZHq3VTzwcylA%2FxNCLTfZrcMH%2Bn Not expensive and always useful Cheers Rich I didn't knew that, I just ordered it. I have read about broken crankshaft but don't know the symptoms. I will put the housing cover plate in place and the belt to make a test Friday when the stethoscope arrive. Edited September 25, 2023 by Michel Higuet Quote Link to post Share on other sites
Malbaby Posted September 25, 2023 Report Share Posted September 25, 2023 Was the oil slinger on the front crank OK?...ie. still enlocated? And the sound is not coming from the rear of the engine/clutch area?? Quote Link to post Share on other sites
Z320 Posted September 26, 2023 Report Share Posted September 26, 2023 On 9/24/2023 at 5:00 PM, Michel Higuet said: Everything was fine with this engine until yesterday, starting from the start of a little ride test, an intermittent noise while driving, nothing when stopped but today same thing and with car stopped I can play with the accelerator and the noise appears from times to times. the noise is loud and sounds like something is seized and running without oil, high-pitched and metallic. Like a water pump bearing. The noise "seemed" to come from under the valve cover but nothing abnormal at first glance. I removed the alternator belt but no play on the water pump or alternator. In the front housing with the timing chain? How to pinpoint the sound? Hi, you use solid spacers between the rockers instead springs. Do they spin free if you try to do this? Ciao, Marco Quote Link to post Share on other sites
Michel Higuet Posted September 26, 2023 Author Report Share Posted September 26, 2023 7 hours ago, Malbaby said: Was the oil slinger on the front crank OK?...ie. still enlocated? And the sound is not coming from the rear of the engine/clutch area?? The oil slinger is in the right position but not enlocated, no key there to located. The sound doesn't seems located to the front or rear. Caution with "it's seems ". Quote Link to post Share on other sites
Michel Higuet Posted September 26, 2023 Author Report Share Posted September 26, 2023 42 minutes ago, Z320 said: Hi, you use solid spacers between the rockers instead springs. Do they spin free if you try to do this? Ciao, Marco Yes I have removed all the train and check on the bench. By the way today I will rebuild the front cover, I have read 120 l/s to secure the front pulley how do you block the car? Quote Link to post Share on other sites
Z320 Posted September 26, 2023 Report Share Posted September 26, 2023 (edited) I make shure cylinders 1 is on the compression stroke, both valves closed. Take my multiple flexible nylon robe which I have for this job on all vehicles, spark plug out and guide some of it with a 15 mm tube in the cylinder. Keep in mind where you are and want to turn, before or after TDC. Or with the engine in the car: 1st gear in, wife on the brake if your handbrake works poor. Have much success Marco Edited September 26, 2023 by Z320 Quote Link to post Share on other sites
Michel Higuet Posted September 26, 2023 Author Report Share Posted September 26, 2023 (edited) I rebuild the front this morning, everything with the belt too. But because the stethoscope come only Friday and no cooling water inside I will check the heather motor fan who doesn't start anymore. The graphic of the sound capture: started with the noise and then the noise disappeared one moment... Edited September 26, 2023 by Michel Higuet Quote Link to post Share on other sites
keith1948 Posted September 26, 2023 Report Share Posted September 26, 2023 Hi Michel Try removing plugs and listen into each cylinder in turn as engine rotates. You might be able to narrow it down to one cylinder. Just wonder if a piston ring has broken up. If it is just one cylinder then put a bit of engine oil into plug hole and see what happens as engine rotating. If noise goes away then you have narrowed it down to that area. Fingers crossed for you Keith Quote Link to post Share on other sites
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