Another thing to check / rule out, perhaps.....??? The metal / rubber bushings and joints in both ends of the reaction control rod ---- link that attaches between the rear cam cover and the luggage boot bulkhead.
In the video when you zoom in during the noise....was that stream of smoke from a cigarette or the engine? Sec. 18
Does your car have a air injection system to the exhaust manifold with the two valves like the later 308qvs have? Maybe if you do a valve is leaking. On my car they where located on the side you suspect. When all else fails read the damn manual. - wife
Many thanks for your replies here Gents. I will try to answer them all in order. Hi Rifledriver, yes I have been doing a lot to the engine etc and distubing things can be a recepie for issues. However I have done 200 miles since finishing all the work with no issues. AND THEN. as soon as I changed the OIL and FILTER it all started. Now the problem I have is that it only does it when hot cranking not warm or cold oil. The other worry is that if I keep trying to replicate the problem I may do some damage during the 15mins of engine idle it takes to even get warm. BUT you are right diagnosis is easier done by replicating the noise, it's a tough choice. The only mistake I made was not marking a cam pully and filming it during cranking however quick thinker here did a calcultion of the frequency, here's what he wrote: 'I counted 11 instances of the sound in about 7 seconds of playback. That's about 95 events per minute. If the starter is turning the crank at near 200 rpm, you're right on the money thinking it's a cam based event.' Smart observation I thought. He also wrote this: 'In order to test oil supply to the suspect bearing, perhaps you could remove the exhaust cam as well. Then you could spin the engine with the starter motor and compare the flow rates across several bearings.' This was a test that I was thinking of doing, his and others suggesting it has made me make this my next test I think, maybe, but options are still open. Mike996: 'Air pulses' Yes I'm trying to convince myself that it is just some noisy breather or something but it sounds too strong and metalic, however it's not discounted in my mind even now. Crowndog: 'Maybe a bad/noisy bypass valve in the filter?'Try the stethoscope on it. You know I did and it seemed to be no noisier there than anywhere else. However could it be anything to do with that filter? It is new. The noise however seemed to be conducting all around the engine even through the stethoscope. My car has no emissions stuff no pumps no aircon nothing. Just an alternator and water pump both disconnected for the video. Finnerty, yes I've had a good old wiggle and pull of stuff but can't even get a squeek, reaction control rod is good also. Andyww: ' Surely the first thing to do (before removing cams but too late now) would be to establish whether the sound repetition is engine speed, half engine speed, or one revolution of the cam belt.' Hi Andy, many folks here seem to feel it's half engine rotation speed. Is 200RPM cranking speed? I didn't varify it for myself, maybe someone can. Steve, the hamster is in my Smart Car at the moment ;-) The 'smoke' is my long hair in the lens. ha ha. Both distributor caps are perfect. Andyww: ' What about the roll pins which secure the rotor arm extensions onto the ends of the camshafts? If one had slipped halfway out it would grind into the recess in the head' Andy, that is a bloody good point! BUT no they are fine. also cambelts are perfect, no rubbing and pulley bearings are super smooth. Many thanks again guys, to be sure I'm going out to the car and double checking (aircraft dual check style) stuff raised here just to be certain. Keep those questions coming, it may unearth something new, or something I missed. Sorry for the long post, lots of stuff here, all the best, Bell Bloke
I think my next step is to at least pull the sump plate, it won't disturb anything but I suspect it will be quite revealing.
If you havn't had it off before, its not as simple as just unbolting the thing - ISTR you need to remove the oil temperature sender from the front of the sump and the dipstick tube - that one can be fun. Also you will find you need to fully remove one of the studs to get it out. ISTR its the middle on but can't recall if its at the back or front of the plate! Suggest you have a read before launching into this - look for threads about replacing the shift shaft seals (which requires removal of same). ETA: here you go - http://www.ferrarichat.com/forum/139559427-post8.html
I think Brian is right when he says oil starvation to a cam bearing would immediately manifest itself in a very obvious way! I would think its more likely to be a well-oiled bearing which is tight. This is what I would do if it were me: Assuming we have concluded its definitely something to do with the rear cams: Replace camshafts, ensure the caps are torqued up to exactly the right value (seem to recall a discussion about low-range torque wrenches!). Check all clearance of distributor, pulleys etc as going. Turn engine away from TDC. Turn cams by hand and feel if either feels "sticky" when turning. If not, replace cam cover with a few nuts and run engine till noise starts. Remove oil filler cap, is noise louder? If so, loosen each cam cap in turn very slightly (dont want to open up the oilway!) and crank engine. See if any cause noise to stop.
Have you got a spare oil filter? Change it. (What brand/type) How's oil filler cap? Rubber ont it's place? No metal clip bend (and touches camlobe)? But only when hot.... Hmmm difficult. You also had it with spark plugs out, waterpump not moving ... - > not compression or waterflow related The lubrication diagram isn't crystalclear in my wsm (copy), but it seems the cams in the rear bank are the last in line in oil delivery. Is it possible the filtertype isn't correct for your car (i double checked my spare filter: Ufi 2316202) but I assume yours came also from SF? (Mine is batch 2673) I reviewed the vid several times but sound is notvmetallic for me, but I use the speaker on the ipad, don't know it's a good reference... Keep us posted
Last suggestion promise. Does your engine have the blow-by system with the oil/vapor separator? If so those are notorious for clogging up with "stuff". Might want to check that out by opening a hose connection to allow free air flow past it.
Hi Bart, the oil filter I ordered was Oil Filter Ferrari number191993 UFI Supersedes: 100325, 111782, 240778, 4170601, 41706011 (Mondial: 8, QV, 3.2) It's from Superformance, BUT on checking it I found it to be numbered UFI 2316202 However they told me it is the right filter when I rechecked. Hey Crowndog don't make it your last suggestion, I haven't actaully blown through the oil vapour seperator yet at all. Will do and will report. Iain cheers for the diagram, thats saved me quite a bit of time. Andyww, that all sounds very sound to me, But I've got to look in that pan first I think because it's fairly non intrusive mechanically and may reveal some nasties. Then after that I will put everything back and proceed with further diagnosis, as suggested. In the meantime a 'wildcard' like engine breather or oil filter might just make a total idiot out of me, by actually being the problem....... Right now I could do with looking like an idiot, if only.. Cheers Gents, Bell Bloke.
Before you do take the pan off you are going to have to drain the oil anyway so I'd do that & have a good look at what's floating around in there first. When you remove the pan itself you may not be able to see much anyway - the crank is hidden behind some kind of splash guard on my 328.
Bell --- Don't loose track of some key clues that have already been proven..... 1) The noise is not occurring at crank rotation rate ---- it is occurring at close to half that. 2) It is not continuous ---- it is periodic These strongly suggest it is NOT coming from the crankcase (crankshaft, journal bearings, or pistons). Also, I would lean away from bearings in general..... Think about this --- if there is drag or interference --- a round thing in a round hole will make a continuous noise during rotation so will an out of round thing in a round hole and so will a round thing in an out of round hole Something is either moving cyclically, or rotating, at approximately 1/2 engine RPM and making contact with something else. Or, it is some strange air / fluid pressure build-up / release phenomenon.
Yes, same on the 308, other than the oil pick up tube assembly (and the windage baffles, which are attached to the bottom pan), you cannot see anything ---- the crankshaft, journals, rods, pistons, etc.......everything is hidden behind the splash guard. Which, IIRC cannot be removed without separating the sump casting from the block. I would not waste your time looking in there, but if you really need to, for your own piece of mind (or raw curiosity ), go ahead. If you find anything in there that is causing the problem, then I owe you a pint
The thing that concerns me guys is those bits of black rubbery stuff that came out when I drained the oil. I'm thinking is the strainer pick-up blocked in anyway...
If the bits make it down to the bottom of the pan, you are pretty safe. From there, there is a screen at the pick up tube to the oil pump, then it goes straight to the oil filter. The filter should screen that out. But, I would cut open your oil filter to see what is in it.
Where did the 200 rpm number come from? I don't know the starter speed at all, but if the starter cranks at 95-100 rpm then you get a completely different diagnosis.
Ok, Bell. I let my old man listen to the noise without any further background info. Only that it happens during hot starting and asked him what came first to his mind. He said, "Cam belt tensioner or any other bearing." Told him about the discussion here and the findings. He doesn't really think it is oil starvation as he mentioned a cam that does not get enough oil makes a different sound and not only with starting. Anyway an option to blow stuff out of the oil way could be done with an aircompressor holding the pistol head with a small o-ring on the oil way hole. (depending where it is blocked (if blocked) it gets out or goes further in)
Hi Brian, You are dead right! I've been trying to find out all day what the cranking RPM is, but so far no luck. I did read the 200rpm figure here somewhere but that can't be relied on. Since now this is a point of diagnosis then I must now get an accurate figure. This I will do when I put the cam back in for and oil flow test. Hi Finnerty, yes I don't want it to seem like I'm randomly tearing my engine down but here's my plan: I don't want to run the engine until I've at least tried to find a cause and remedy it. I would absolutely kick myself if having had a good audible warning I were to persist in running it only to have a catastophic failure that punched a hole in the block or caused bearings to spin on the crank, well you get the picture. At the same time I want to keep some kind of perspective and not tear the engine to pieces just to find out that it was all a bad case of 'Crowndogs Wind' ;-) What Next: Since oil might be the issue I thought just have a look at the oil strainer check it is clear and get any left over debris out of the sump. Next I'd like to see big ends and mains but if that is too bigger task I will check for binding using engine rotation method. Next I will put back all the cams and varify oil flow under cranking only. If good, then run engine, If bad.......well we open a door into another room and off we go again ha ha. And I do need to varify starter speed, a lot rests on that. Tomorrow I'm checking crank breather and other stuff suggested. Cheers Guys, thankyou so much for your ideas, Bell ;-)
Hi Mvt, tensioners are the first thing I checked they are smooth as silk. How about main bearings or rod bearings, cos I'm starting to get a bad feeling about this. Ask him what he thinks, Dads know everything. I know my dad would have known damn it, Cheers, Bell.
FYI most starters will turn an engine over from between 200 to 500 rpm depending on a variety of factors. load, tooth ratio, voltage etc.. For a quick check any decent spectrum analyser app will be able to give you a fq count. have you tried turning the engine over by hand? is there any crankcase pressure being built up? there is no real way to inspect the crank or rods with the engine mounted to the transmission case, they need to be separated for that. Dave, aka Finnerty is right, any bearing or round contact surface is going to make a constant noise, albiet at horrible sounding frequencies but a cyclic sound will only come from cyclic movement. those are easy to locate in an engine.. pistons and rings valves and guides oil pressure relief valve
Hi Guys, no last time I cranked it by hand I was going way to slow, I need to remove all the plugs tomorrow and see if there is any binding. Retrospective thinking is making me think rod No 4. since the noise seemed to be around that cylinder, that's why I pulled those cams that side because the sound was from around there. What I don't get is why it would fail suddenly and why is the oil pressure still normal.
