So my 85 jag with 212k miles on it was working fine having driven over 200 miles in that past few days that it was working. I had driven it 30 miles or so in the morning and came home just fine. When I went to start it up later this is what I heard. Any ideas?
Could be a split in one of the fan belt pully or a slipping pully loose key way or bolt come loose on pully.
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Jabraan,
Can you identify exactly where in the engine bay this noise is coming from? I have an inexpensive “mechanics stethoscope” that I purchased at a local auto parts store for less than $10 US that I use for pinpointing noises.
As Gary poined out it is possible that the noise is coming from a accessory pulley like from a power steering pump, air pump, or air conditiong compressor. These components are located towards the front of the engine. It is also possible that the noise is coming from inside the engine itself like a loose tappet guide. Identifying the source of specific location of the noise would help diagnosis.
I recommend that you don’t drive the car until we sort this out the source of the noise.
Paul
Take all the belts off and see if the noise is still there that should determine if its internal or external.
Dosen’t sound like buckets or internal to me.
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Hi and welcome. I would try to isolate where the noise is coming from. Perhaps it might be a cam bucket guide. The guide is a fixed cylinder that each can follower operates (up and down) within. The guides are known to come loose and move up and down striking the cam itself as it rotates. Usually the exhaust side. I would use a mechanic’s stethoscope or a long screwdriver to the ear to isolate the source. Start with the exhaust cam cover. Get back to us with your findings - there are cures for this issue - if it is the cam bucket guide problem. Paul
So I have concluded the the noise is coming from the front of the engine. I’m not sure if if it’s the accessories I haven’t gotten there yet I started the car to drive it on my ramps to do an oil change and the noise was different imo I’ll get a video up for you guys. I did take off the exhaust side cam cover and everything looked ok to me
. https://youtu.be/GoMLiVecUaA Here is the video I just made. When I revved it I seemed to have brought up another noise. Still hoping the oil filter is clogged and has something to do with it I’m gonna replace it later…
I have to concur: hard to say, definitively, but it seems external to the engine.
Disconnecting all external accessories will show that up.
I have also heard broken flex plates sound like that.
Also I noted while making that video is the sound didn’t seem as much revved based as i thought it was
I would say it’s not a broken flex plate as it’s definitely coming from the front …
Poke around with a mechanics stethoscope to see if you can identify the source of the noise but be careful for moving parts. There are a number of components that could make that noise. Does you car have an air pump?
Paul
Yeah it does still have the air pump. Tho since it’s right there I don’t think that’s the cause of the noise or it would’ve been more easily detectable
Take the belts off, see if its still there.
Yes that’s the plan if after the oil change tomorrow if the sound stays the same I’d say it means the noise from the outside if it changes then I’d say it coming from the engine
I couldn’t detect any change in the sound when the engine was revd up. The frequency seemed to stay at the same resonance?
Yeah it seemed to stay the same since I was revving the engine quick and the sound didnt change What would that be?
I suppose it could be the auxiliary cooling fan. It is located beneath and behind the front bumper and is an electric motor, so it does not operate at engine speed and reving the engine would have no affect on its speed. The auxiliary cooling fan only comes on with coolant temperatures around 105C unless the wiring has been modified. Still I suppose that it could be the auxiliary cooling fan hitting against something. It is certainly worth a look to see if that is it. With the engine OFF and the key out of the ignition, look at the auxiliary cooling fan and spin the fan blade to see if it moves freely and there is no obvious damage to it or it’s shroud. Then disconnect the connector that is nearby the fan to cut off power to the auxiliary cooling fan. Then start up the engine. If the noise is gone then you found the problem. It is a long shot, but worth a try.
Paul
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Sounds like the rattle of a loose shield, Jabraan - or some similar metal to metal contact external to the engine…
Frank
xj6 85 Sov Europe (UK/NZ)
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I will check again and make a video of the engine running after I do the oil change. Tho looking at the aux fan* infront of the radiator I can see leaves and stuff sitting. Seems like it hasn’t turned on in a while. Which is weird because I’ve driven the car about 1500 miles in the past couple months
Jabraan,
I have no idea where in the world you live and what your climate is like, but here in Southern California the auxiliary cooling fans in my 1984 XJ6 Vanden Plas doesn’t come on very often. It will primarily come on during the hottest of days when driving up a long hill with the air conditioning running. The coolant temperature needs to reach about 105C or so before it will normally come on.
I suppose that an electrical problem with wiring or a relay could result with the auxiliary cooling fan coming on when it normally shouldn’t, and if you have leaves and other debris around it that could result in a noise like you are experiencing.
A thorough inspection of that area and cleaning out of the leaves is certainly a good thing to do regardless.
Paul
Although I don’t personally think that’s where the noise is coming from I will recheck. Also I live in Dallas Texas so it is pretty hot here but my ac doesn’t work… right now my next step is to do an oil change and look inside the filter and also see if it makes any difference to the noise