Looks like I need timing chain work. URGENT ADVICE NEEDED
#121
03-31-2011, 12:09 PM
Veteran Member
You're right. If there was a cam timing issue the engine would not run right, but you might stumble onto something else while checking. Also, a head gasket leak or an exhaust manifold leak can sound like a knock or a heavy tick and a compression check could show a head gasket problem. I just hate to see you and your Jag go down the tubes. It looks like a nice car. Does your uncle have a stethescope ? or something like a big screwdriver or a piece of small hose put to your ear (be careful of course) to try and locate the noise ? Maybe you can at least tell whether it is top-end or bottom-end.
#122
03-31-2011, 03:56 PM
Veteran Member
@ Chinny, I honestly didn't get your message. keep on with the info. No CEL may means no electrical faults to report, i.e. a coilpack/spark issue, or knock sensor, or emissions etc. This is machanical.
No chain slack, mate these are not connected to the drive - they're the cam timing secondaries, so will have tension across the two sprockets either side unless snapped. The chain slap I suspect, is in the long chains driving the secondaries, i.e. the primaries.
To tension the primaries, there are chain guides, long blades the chains run on, if you have a guide fail, or the tensioner behind it, you have a loose primary chain with no tension, think about a push bike with it's chain too long, imagine it going over a bump and watch the chain dance and sway....this I think is what's occurring behind that timing cover I mentioned you should take off.
At this point I'd confirm the timing as this is the weak link. Having rebuilt my motor the bottom end is indeed bomb proof to a point. You have oil in it?
Don't drop the pan as yet, check the timing components and get back to us. You might just have to spring for tensioners and a gasket or two and some new oil and filter. I'm optimistic about this and you should be too. There are pictoral how to's on getting the cover off and swapping the bits. Gather the documents, tools and have a go. Next is to remove and fit. Fingers crossed.
No chain slack, mate these are not connected to the drive - they're the cam timing secondaries, so will have tension across the two sprockets either side unless snapped. The chain slap I suspect, is in the long chains driving the secondaries, i.e. the primaries.
To tension the primaries, there are chain guides, long blades the chains run on, if you have a guide fail, or the tensioner behind it, you have a loose primary chain with no tension, think about a push bike with it's chain too long, imagine it going over a bump and watch the chain dance and sway....this I think is what's occurring behind that timing cover I mentioned you should take off.
At this point I'd confirm the timing as this is the weak link. Having rebuilt my motor the bottom end is indeed bomb proof to a point. You have oil in it?
Don't drop the pan as yet, check the timing components and get back to us. You might just have to spring for tensioners and a gasket or two and some new oil and filter. I'm optimistic about this and you should be too. There are pictoral how to's on getting the cover off and swapping the bits. Gather the documents, tools and have a go. Next is to remove and fit. Fingers crossed.
#123
03-31-2011, 04:31 PM
@ Chinny, I honestly didn't get your message. keep on with the info. No CEL may means no electrical faults to report, i.e. a coilpack/spark issue, or knock sensor, or emissions etc. This is machanical.
No chain slack, mate these are not connected to the drive - they're the cam timing secondaries, so will have tension across the two sprockets either side unless snapped. The chain slap I suspect, is in the long chains driving the secondaries, i.e. the primaries.
To tension the primaries, there are chain guides, long blades the chains run on, if you have a guide fail, or the tensioner behind it, you have a loose primary chain with no tension, think about a push bike with it's chain too long, imagine it going over a bump and watch the chain dance and sway....this I think is what's occurring behind that timing cover I mentioned you should take off.
At this point I'd confirm the timing as this is the weak link. Having rebuilt my motor the bottom end is indeed bomb proof to a point. You have oil in it?
Don't drop the pan as yet, check the timing components and get back to us. You might just have to spring for tensioners and a gasket or two and some new oil and filter. I'm optimistic about this and you should be too. There are pictoral how to's on getting the cover off and swapping the bits. Gather the documents, tools and have a go. Next is to remove and fit. Fingers crossed.
No chain slack, mate these are not connected to the drive - they're the cam timing secondaries, so will have tension across the two sprockets either side unless snapped. The chain slap I suspect, is in the long chains driving the secondaries, i.e. the primaries.
To tension the primaries, there are chain guides, long blades the chains run on, if you have a guide fail, or the tensioner behind it, you have a loose primary chain with no tension, think about a push bike with it's chain too long, imagine it going over a bump and watch the chain dance and sway....this I think is what's occurring behind that timing cover I mentioned you should take off.
At this point I'd confirm the timing as this is the weak link. Having rebuilt my motor the bottom end is indeed bomb proof to a point. You have oil in it?
Don't drop the pan as yet, check the timing components and get back to us. You might just have to spring for tensioners and a gasket or two and some new oil and filter. I'm optimistic about this and you should be too. There are pictoral how to's on getting the cover off and swapping the bits. Gather the documents, tools and have a go. Next is to remove and fit. Fingers crossed.
#124
04-01-2011, 03:24 AM
Veteran Member
We're STILL speculating - info on the state of the timing system is required first before we can progress.
#125
04-01-2011, 03:44 AM
Chinny, to turn the engine (and check the cam flat alignement) turn the engine clockwise (viewed from the front of the car) using a 24mm socket wrench on the big belt drive pulley on the front of the engine.
It helps to remove the spark plugs.
If the cam flats align your engine timing is not the issue.
David
It helps to remove the spark plugs.
If the cam flats align your engine timing is not the issue.
David
Last edited by DavidN; 02-23-2012 at 11:58 AM.
#126
04-01-2011, 06:20 AM
Veteran Member
#127
04-01-2011, 08:17 AM
[quote=thinkpad_master;308175]
I was told by a Jag specialist that the design of these things has changed four times as well.
Something I am noticing with the tensioners, is they can cause problems even if they are the metal ones. As Chinny said, a piece of the tensioner fell into the oil system and clogged one of the bearing oil channels, which eventually ruined the engine. The new tensioners, although metal, do have a plastic piece on top of them that will be worn down by the timing chain. It will eventually fall off the tensioner and go down into the engine. Not only can the plastic cause trouble, but the chain will start wearing very quickly because it will now be ridding across the metal portion of the tensioner. This is what happened to mine, except without a fried engine. Granted it was one of the old tensioners, but the same thing could still happen with the new ones.
quote]
That's the thing. I wouldn't mind if Jaguar said at this many miles or years put new tensioners in. But nowhere do they mention this service. It's all up to the owners. And most people don't know about it.
quote]
That's the thing. I wouldn't mind if Jaguar said at this many miles or years put new tensioners in. But nowhere do they mention this service. It's all up to the owners. And most people don't know about it.
#128
04-01-2011, 10:41 AM
Ok...so apparently the increasing amount of spun rod bearings is true.
I consulted Jaguarforums.co.uk and informed them of my issue and asked if they've heard of it.
Jaguar Forum.co.uk • View topic - USA Jag Owner Needs Help! ConRod Spun!
They quoted a website from a very high end Jaguar parts/service/shop/specialist:
Occasionally the lubrication system fails, the bearings of No.1 big end suffering starvation due to low oil level. For
this reason alone it is sensible to check the engine oil level on a regular basis as even a slight lowering of the level
can cause loss of oil pressure on cornering. The 4.2 has a totally redesigned oil system utilising a central pickup and
incorporating piston and timing chain oil jets to further aid lubrication and cooling.
Racing Green Cars are now seeing Jaguar V8 engines having covered quite high mileages or having thrown a bearing.
On dismantling these engines it is often found that the crankshaft is too badly worn to re- use with the bearings
available from Jaguar. This is generally the case where the cars have been run with low oil levels at some stage
in their lives. Oversize engine bearings are not available from Jaguar for this engine for reasons that are not known.
Where a crankshaft is found to be excessively worn the only resolution up until now has been to purchase a new
crankshaft and bearing kit from Jaguar as and when these have been available.
So to see if this was true, I sent an email to:
I think at this point it's pretty conclusive. My mom is forcing me to sell a car and in return she's going to help me pay for a new leased car with a Warranty.
It's been short but I just want to thank everyone from the bottom of my heart for trying to figure things out. I'm so maddened that my time owning such an amazing car was so short lived and such crappy things had to happen.
Sean B, JimmyL, Burmaz, all of ya. Thank you very much for the help and support. I wish I could remain optimistic but it's gotten to the point of being out of my hands and will power.
I feel like people who own these cars need to be informed that rod bearings are becoming a known issue for these AJv8s and owners need to be sure to keep on top of the oil levels. I think my case is a massive warning to all of those out there.
I consulted Jaguarforums.co.uk and informed them of my issue and asked if they've heard of it.
Jaguar Forum.co.uk • View topic - USA Jag Owner Needs Help! ConRod Spun!
They quoted a website from a very high end Jaguar parts/service/shop/specialist:
Occasionally the lubrication system fails, the bearings of No.1 big end suffering starvation due to low oil level. For
this reason alone it is sensible to check the engine oil level on a regular basis as even a slight lowering of the level
can cause loss of oil pressure on cornering. The 4.2 has a totally redesigned oil system utilising a central pickup and
incorporating piston and timing chain oil jets to further aid lubrication and cooling.
Racing Green Cars are now seeing Jaguar V8 engines having covered quite high mileages or having thrown a bearing.
On dismantling these engines it is often found that the crankshaft is too badly worn to re- use with the bearings
available from Jaguar. This is generally the case where the cars have been run with low oil levels at some stage
in their lives. Oversize engine bearings are not available from Jaguar for this engine for reasons that are not known.
Where a crankshaft is found to be excessively worn the only resolution up until now has been to purchase a new
crankshaft and bearing kit from Jaguar as and when these have been available.
So to see if this was true, I sent an email to:
Originally Posted by Chinny4290
Hi there. I am emailing you guys from the US because you were mentioned in my thread at JaguarForums UK and I need some advice.
I bought an X308 XJ Sport in November of 2010 with the 4.0L AJ27. It had 98k miles on it and not too long ago at 102k miles I developed what seems to be a rod knock. I was given a description from your website that someone else quoted:
Occasionally the lubrication system fails, the bearings of No.1 big end suffering starvation due to low oil level. For
this reason alone it is sensible to check the engine oil level on a regular basis as even a slight lowering of the level
can cause loss of oil pressure on cornering. The 4.2 has a totally redesigned oil system utilising a central pickup and
incorporating piston and timing chain oil jets to further aid lubrication and cooling.
Racing Green Cars are now seeing Jaguar V8 engines having covered quite high mileages or having thrown a bearing.
On dismantling these engines it is often found that the crankshaft is too badly worn to re- use with the bearings
available from Jaguar. This is generally the case where the cars have been run with low oil levels at some stage
in their lives. Oversize engine bearings are not available from Jaguar for this engine for reasons that are not known.
Where a crankshaft is found to be excessively worn the only resolution up until now has been to purchase a new
crankshaft and bearing kit from Jaguar as and when these have been available.
I removed the valve covers hope to see a loose timing chain and worn secondary tensioners but they seemed to be in good condition. The tensioners didn't seem worn and there were no cracks and the chain had no slack in it when I pulled on it. However, after describing this, two large online Jaguar communities have either never heard of a bottom end failure on these engines or think it's something else. Before I take more time to figure out what went wrong, I'd like to hear what you guys have to say.
I recorded two videos, the first with a cold startup sound to record the knock and the valve cover assessment. Would you guys be able to tell me from my videos and information if I have a rod knock? I have had two mechanics told me it was a rod knock but their assessment was "starting the engine and listening" and dropping the oil to find "metal shavings." I have yet to do this myself but I got as far as removing the valve covers. On the other hand, several members in both communities tell me that it doesn't sound like a rod knock off the bat and to check compression.
If there's any advice you guys can give, I would greatly appreciate it. Has this happened before? Are there strong chances for my engine to have spun a rod bearing? Simply put, even though I'm an avid DIYer, I don't have the money to buy a complete new engine since I replaced the transmission 3 weeks after I bought it. If it is a spun rod bearing I'm selling the car for restoration. If there's an off chance that it could be something else, I will continue to work on the car.
Here are the videos.
~~~~~
Thanks for any help.
Chris
I bought an X308 XJ Sport in November of 2010 with the 4.0L AJ27. It had 98k miles on it and not too long ago at 102k miles I developed what seems to be a rod knock. I was given a description from your website that someone else quoted:
Occasionally the lubrication system fails, the bearings of No.1 big end suffering starvation due to low oil level. For
this reason alone it is sensible to check the engine oil level on a regular basis as even a slight lowering of the level
can cause loss of oil pressure on cornering. The 4.2 has a totally redesigned oil system utilising a central pickup and
incorporating piston and timing chain oil jets to further aid lubrication and cooling.
Racing Green Cars are now seeing Jaguar V8 engines having covered quite high mileages or having thrown a bearing.
On dismantling these engines it is often found that the crankshaft is too badly worn to re- use with the bearings
available from Jaguar. This is generally the case where the cars have been run with low oil levels at some stage
in their lives. Oversize engine bearings are not available from Jaguar for this engine for reasons that are not known.
Where a crankshaft is found to be excessively worn the only resolution up until now has been to purchase a new
crankshaft and bearing kit from Jaguar as and when these have been available.
I removed the valve covers hope to see a loose timing chain and worn secondary tensioners but they seemed to be in good condition. The tensioners didn't seem worn and there were no cracks and the chain had no slack in it when I pulled on it. However, after describing this, two large online Jaguar communities have either never heard of a bottom end failure on these engines or think it's something else. Before I take more time to figure out what went wrong, I'd like to hear what you guys have to say.
I recorded two videos, the first with a cold startup sound to record the knock and the valve cover assessment. Would you guys be able to tell me from my videos and information if I have a rod knock? I have had two mechanics told me it was a rod knock but their assessment was "starting the engine and listening" and dropping the oil to find "metal shavings." I have yet to do this myself but I got as far as removing the valve covers. On the other hand, several members in both communities tell me that it doesn't sound like a rod knock off the bat and to check compression.
If there's any advice you guys can give, I would greatly appreciate it. Has this happened before? Are there strong chances for my engine to have spun a rod bearing? Simply put, even though I'm an avid DIYer, I don't have the money to buy a complete new engine since I replaced the transmission 3 weeks after I bought it. If it is a spun rod bearing I'm selling the car for restoration. If there's an off chance that it could be something else, I will continue to work on the car.
Here are the videos.
~~~~~
Thanks for any help.
Chris
Originally Posted by Reply from Racing Green Cars
Hi Chris
I will cut to the chase; that is definitely big end knock and almost certainly No1 cylinder. Sorry
Regards
Martin
Racing Green Cars
I will cut to the chase; that is definitely big end knock and almost certainly No1 cylinder. Sorry
Regards
Martin
Racing Green Cars
It's been short but I just want to thank everyone from the bottom of my heart for trying to figure things out. I'm so maddened that my time owning such an amazing car was so short lived and such crappy things had to happen.
Sean B, JimmyL, Burmaz, all of ya. Thank you very much for the help and support. I wish I could remain optimistic but it's gotten to the point of being out of my hands and will power.
I feel like people who own these cars need to be informed that rod bearings are becoming a known issue for these AJv8s and owners need to be sure to keep on top of the oil levels. I think my case is a massive warning to all of those out there.
Last edited by chinny4290; 04-01-2011 at 10:44 AM.
The following users liked this post:
JimmyL (04-01-2011)
#129
04-06-2011, 09:50 PM
Ok, sorry to revive this thread but I sitll have the car in my possession while it sits on eBay.
Someone shot me a message and suggested for me to look at the transmission torque converter/flex plate. Since I JUST had my transmission replaced in December, what are the chances of it being the flex plate? From poor workmanship maybe? 0.o
Someone shot me a message and suggested for me to look at the transmission torque converter/flex plate. Since I JUST had my transmission replaced in December, what are the chances of it being the flex plate? From poor workmanship maybe? 0.o
#130
04-06-2011, 09:59 PM
It could have loosened up where it bolts to the torque converter or cracked at the crank bolts area.
You still have to have a trained ear to determine if it is a flex plate issue, rod bearing or other noise maker.
Tests can be made while its running that can eliminate some possibilities.
Explaining tests without having the vehicle involved in the testing is useless.
#131
04-07-2011, 09:39 AM
Veteran Member
First off I definitely would not try and start the engine!!!!!!! Have the new shop you are going to pull the cam covers off and look at the timing chains and tensioners. I definitely think you have jumped at least one tooth on one side. I just replaced the upper tensioners on my XK8 4.0 engine and posted a thread with twelve pictures showing what it looks like in there. Go to XK8-XKR 98-2003 and find my thread with the pictures and see what it looks like in there. I didn't have a failure it was preventative. But don't start the engine until you know for sure it is not the timeing chains.
EZDriver
EZDriver
#132
04-07-2011, 02:17 PM
Veteran Member
#133
04-07-2011, 03:24 PM
I've done a once-over on this thread and find several points somewhat confusing. A bad rod-bearing doesn't, in my experience, whine. It rattles, or perhaps, thumps is a better word. My first thought is a chain guide has shucked the plastic wear surface and the chain is rubbing on the metal backing. JMO
KS
KS
#134
04-07-2011, 05:51 PM
First off I definitely would not try and start the engine!!!!!!! Have the new shop you are going to pull the cam covers off and look at the timing chains and tensioners. I definitely think you have jumped at least one tooth on one side. I just replaced the upper tensioners on my XK8 4.0 engine and posted a thread with twelve pictures showing what it looks like in there. Go to XK8-XKR 98-2003 and find my thread with the pictures and see what it looks like in there. I didn't have a failure it was preventative. But don't start the engine until you know for sure it is not the timeing chains.
EZDriver
EZDriver
#135
04-08-2011, 01:53 AM
Veteran Member
#136
04-08-2011, 01:54 AM
Veteran Member
I've done a once-over on this thread and find several points somewhat confusing. A bad rod-bearing doesn't, in my experience, whine. It rattles, or perhaps, thumps is a better word. My first thought is a chain guide has shucked the plastic wear surface and the chain is rubbing on the metal backing. JMO
KS
KS
#137
04-09-2011, 06:13 PM
GUYS MAJOR BREAK THROUGH
Ok. So I took the advice of considering the transmission flex plate since I just had it replaced, so I'm guessing that it could be from poor workmanship.
Here's what I did:
I reconnected everything and removed the ignition wires to the coils one by one with the engine running (WHY DIDNT I DO THIS BEFORE)
NONE OF THEM MADE ANY SIGNIFICANT DIFFERENCE TO THE KNOCK.
I closely followed the knock and it really sounds like its coming from where the transmission and the engine meet (I didn't realize how short these engines are front to back!)
That said, if this is the case then it should be FULLY covered under my transmission warranty.
My final question before I call a tow and send it to my transmission shop, can a malfunctioning flex plate cause an intermittent rough idle? Because the idle was slightly rough and surged a little but only intermittently. And is there still a slim chance there's a main bearing failure? Because in my mind, if removing the ignition wires one by one yielded no change to the knock, would this process still leave the possibility of a big end failure?
Also, I had to disconnect the oil dipstick pipe so I could remove the valve cover on the driver side, since the pipe was supported by a valve cover bolt. How do I reconnect it? Some oil escaped because I forgot to disconnect it.
What do you guys think?
Ok. So I took the advice of considering the transmission flex plate since I just had it replaced, so I'm guessing that it could be from poor workmanship.
Here's what I did:
I reconnected everything and removed the ignition wires to the coils one by one with the engine running (WHY DIDNT I DO THIS BEFORE)
NONE OF THEM MADE ANY SIGNIFICANT DIFFERENCE TO THE KNOCK.
I closely followed the knock and it really sounds like its coming from where the transmission and the engine meet (I didn't realize how short these engines are front to back!)
That said, if this is the case then it should be FULLY covered under my transmission warranty.
My final question before I call a tow and send it to my transmission shop, can a malfunctioning flex plate cause an intermittent rough idle? Because the idle was slightly rough and surged a little but only intermittently. And is there still a slim chance there's a main bearing failure? Because in my mind, if removing the ignition wires one by one yielded no change to the knock, would this process still leave the possibility of a big end failure?
Also, I had to disconnect the oil dipstick pipe so I could remove the valve cover on the driver side, since the pipe was supported by a valve cover bolt. How do I reconnect it? Some oil escaped because I forgot to disconnect it.
What do you guys think?
Last edited by chinny4290; 04-09-2011 at 06:20 PM.
#139
04-09-2011, 07:29 PM
I closely followed the knock and it really sounds like its coming from where the transmission and the engine meet (I didn't realize how short these engines are front to back!)
My final question before I call a tow and send it to my transmission shop, can a malfunctioning flex plate cause an intermittent rough idle? Because the idle was slightly rough and surged a little but only intermittently. And is there still a slim chance there's a main bearing failure? Because in my mind, if removing the ignition wires one by one yielded no change to the knock, would this process still leave the possibility of a big end failure?
What do you guys think?
My final question before I call a tow and send it to my transmission shop, can a malfunctioning flex plate cause an intermittent rough idle? Because the idle was slightly rough and surged a little but only intermittently. And is there still a slim chance there's a main bearing failure? Because in my mind, if removing the ignition wires one by one yielded no change to the knock, would this process still leave the possibility of a big end failure?
What do you guys think?
Very slight chance its a rod bearing
Good chance its the flex plate. Maybe the bolts to the torque converter came loose.
Last edited by Frank M; 04-09-2011 at 07:31 PM.
