FDR
Dedicated LVC Member
I showed the video to a tech and he was confident it's the bottom end letting go. He said if it was outside/behind the engine, it would happen at all RPM. Thoughts?
Timing chain caught up to me
- Thread starter FDR
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joegr
Dedicated LVC Member
It's possible, but it seems to be very rare on these engines. I think that the flex plate or Torque converter guess was a good one. Also, make sure the fan isn't hitting anything (should hear it all the time if it were, though). You could take the lower oil pan off and see if you can see anything.
Telco
Dedicated LVC Member
I've had a bottom end let go, and there's usually a nice, deep, sickening knock at the bottom even at idle. My flexplate didn't knock at idle until it was almost completely split. When the shop replaced it (I was 16 at the time and knew nothing about cars at all), there was 1/4 inch of steel holding the flexplate together, broken along the torque converter bolts.
FDR
Dedicated LVC Member
So the car needs to go to a shop and most likely have the transmission pulled? I most likely don't have the excuse of "while I'm here..." to build up the engine a little bit? The pre-03 (for firing order) Jag 4.2L cranks seem like they should work haha
FDR
Dedicated LVC Member
Well that's disturbing.
FDR
Dedicated LVC Member
Went to the original photo. Looks to just a combination of oil residue and a crappy camera
FDR
Dedicated LVC Member
Well, after finding a video of a Jag 4.0 making the same sound, I finally decided to take a look at this Schrodinger's cat of a problem and find out if I have rod knock/spun bearing. I did the test with the straw in the spark plug hole while cranking by hand, followed by a push of a screwdriver after TDC to confirm.
Piston 7 has at least 1/8" of play.
I guess if you treat it like a race car, expect race car repairs. Maybe it had something to do with low oil, a hard turn, and hard acceleration. Maybe it was my fault for misreading the dipstick. Maybe the shop underfilled it. Maybe the oil level is/was fine. Maybe it was something set in to play thousands of miles before I noticed it. Whatever it was, the engine now has to come out.
Piston 7 has at least 1/8" of play.
I guess if you treat it like a race car, expect race car repairs. Maybe it had something to do with low oil, a hard turn, and hard acceleration. Maybe it was my fault for misreading the dipstick. Maybe the shop underfilled it. Maybe the oil level is/was fine. Maybe it was something set in to play thousands of miles before I noticed it. Whatever it was, the engine now has to come out.
RigsLS
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Ironic, I came across that same video a couple weeks back but couldn't find my way back to it when I thought of posting it for ya.
Was it the one, where a foreign guy, a mechanic at a shop, had gotten his hands on it after others had replaced the entire timing on it and it still made the noise, he went into detail on everything he had checked, (even provided a couple of drawings) had the entire top end off and showed how, when he turned it to just past top dead center, he pushed down on the piston in the front right bank, and it dropped down along with a slight knock?
If so, same vid I saw and was thinking of your problem.
Why do they call that a spun bearing, when the piston is able to drop a bit like that?
Do you still have that link to that youTube vid?
Was it the one, where a foreign guy, a mechanic at a shop, had gotten his hands on it after others had replaced the entire timing on it and it still made the noise, he went into detail on everything he had checked, (even provided a couple of drawings) had the entire top end off and showed how, when he turned it to just past top dead center, he pushed down on the piston in the front right bank, and it dropped down along with a slight knock?
If so, same vid I saw and was thinking of your problem.
Why do they call that a spun bearing, when the piston is able to drop a bit like that?
Do you still have that link to that youTube vid?
FDR
Dedicated LVC Member
They're not normal bearings with balls or needles and two moving sides. They're just cylinders (split into two halves) with oil channels. That oil prevents contact between the bearing and whatever's inside it. Whether the bearing shifts or continues to spin, a split second after the oil inlet is blocked, the shaft makes contact with the bearin and starts grinding it down very quickly. When the knock is noticeable, there's little to no bearing left, so the piston has a few extra millimeters of freedom. Leave it unfixed and continue to run it and the parts will grind each other down until something snaps. Or the knocking iitself (combustion pushing the piston and rod into the crank journal) can snap the crank or rod. Regardless, you dont want any internals breaking free at speed.
It's practically gaurunteed that the crank and rod are scored and gouged beyond repair, which aren't exactly available any more.
It's practically gaurunteed that the crank and rod are scored and gouged beyond repair, which aren't exactly available any more.
FDR
Dedicated LVC Member
Jaguar XK 4.0
https://www.youtube.com/watch?v=4XYoF6G44mw
Runs engine at 1:47, goes into the hand cranking/pushing/explanation around 3:00.
And then there's this video of another 4.0 that was posted to a thread that was inconclusively (but likely) spun bearing, with an identical sound to mine. Can't find the thread, but nothing really of value
https://www.youtube.com/watch?v=wwaK3PqdpCE
FDR
Dedicated LVC Member
Chevy LS? No, too many wires.
But a Jag 4.2 S/C's crank, rods, pistons, intake, and supercharger................ I'm reviewing my options. All options involve keeping the LS.
But a Jag 4.2 S/C's crank, rods, pistons, intake, and supercharger................ I'm reviewing my options. All options involve keeping the LS.
Deaconblue
Well-Known LVC Member
So you have 71K miles on your Gen I V8 engine and spun a rod bearing - sorry to hear about the problem.
What engine oil do you use - brand, type and weight? How often do you change it?
What engine oil do you use - brand, type and weight? How often do you change it?
FDR
Dedicated LVC Member
I've had the car since 64k, so my actions aren't the most indicative of "what not to do". I aimed for 4-5k oil changes. I don't currently have a record of when I got them and I don't remember if I even got 2 yet because I just tag my oil changes on to other repairs. Regardless, it would be whatever brand the dealer uses (Motorcraft? Should be 5w20 though). I can check on brand and oil change dates and get back to you.
There is a chance it was underfilled or it has lost oil. When I pull the dipstick, the oil goes fully across the dipstick to a little bit under the Min dot, but has a stripe run up the side into the safe area. I'll take a picture later. If it's low, shop error? User error? Even if it was a little low, I have a habit of making hard turns in the LS (because fun) so the oil could have moved away from the pump or foamed up and sent an air bubble.
There is a chance it was underfilled or it has lost oil. When I pull the dipstick, the oil goes fully across the dipstick to a little bit under the Min dot, but has a stripe run up the side into the safe area. I'll take a picture later. If it's low, shop error? User error? Even if it was a little low, I have a habit of making hard turns in the LS (because fun) so the oil could have moved away from the pump or foamed up and sent an air bubble.
Deaconblue
Well-Known LVC Member
Okay, without knowing the complete service history on the engine, its really hard to say when the rod bearing(s) could have been damaged. It could have been short filled by unknowing techs at a quick oil change place a few times or a PO could have changed the oil at 10K mile intervals - you just never know without the records.
I haven't looked at the inside of the V8 oil pan to know if it is properly baffled for sustained high-G loads. My initial guesstimate would be that it is not. It does have an odd side to side shape, sort of like the C5 Corvette "bat wing" oil pan. IIRC, the Gen I V8 calls for 5W-30, while the Gen II call out was switched to 5W-20, most likely for CAFE rating reasons. Since critical data such as rod and main bearing clearances are hard to come by for the Gen II V8 , no one knows for sure if any internal changes were made to the design specifications for this switch in oil weight or not.
In general, I am not a fan of the 5W-20 oil - variable valve timing or not. I don't use it in the Gen II V8 unless I mix it with 5W-30 at least half by volume. I also use Mobil 1 High Mileage oil which is still rated SL and has higher levels of zinc and phosphorus additives - especially since the V8 engine has direct action buckets on the cam lobes.
I have owned other Ford "orphan" engines/cars such as the original Taurus SHO with the Yamaha V6. The rod bearings in that engine were notorious for giving up the ghost - so badly so that we would joking recommended that the rod bearing be swapped at the same 60K interval as the timing belt. Instead of the recommend 5W-30 weight, I ran 10W-40 oil for street use and switched to 20W-50 oil for track days in that engine for added protection.
I haven't looked at the inside of the V8 oil pan to know if it is properly baffled for sustained high-G loads. My initial guesstimate would be that it is not. It does have an odd side to side shape, sort of like the C5 Corvette "bat wing" oil pan. IIRC, the Gen I V8 calls for 5W-30, while the Gen II call out was switched to 5W-20, most likely for CAFE rating reasons. Since critical data such as rod and main bearing clearances are hard to come by for the Gen II V8 , no one knows for sure if any internal changes were made to the design specifications for this switch in oil weight or not.
In general, I am not a fan of the 5W-20 oil - variable valve timing or not. I don't use it in the Gen II V8 unless I mix it with 5W-30 at least half by volume. I also use Mobil 1 High Mileage oil which is still rated SL and has higher levels of zinc and phosphorus additives - especially since the V8 engine has direct action buckets on the cam lobes.
I have owned other Ford "orphan" engines/cars such as the original Taurus SHO with the Yamaha V6. The rod bearings in that engine were notorious for giving up the ghost - so badly so that we would joking recommended that the rod bearing be swapped at the same 60K interval as the timing belt. Instead of the recommend 5W-30 weight, I ran 10W-40 oil for street use and switched to 20W-50 oil for track days in that engine for added protection.
FDR
Dedicated LVC Member
My oil cap says 5w20, as does the 01 and 02 owners manuals.
I last got the oil changed at ~66k and was due at 71,850. I'm currently at 71,245, so I was 600 miles away from a 5k interval. If the oil wasn't low after changing it, it's certainly low now. It doesn't even fully pass the twist at the bottom of the dipstick. The "side stripe" of oil running up the side of the dipstick was most likely just some drippings from pulling the dipstick out of the tube. It's not present now. But today the dipstick had some metal shavings, which hasn't happened before, but I've already confirmed piston play.
I think I'll go back to the "excessive" 3-4k intervals.
Now the question (which probably won't be answered) is "where did it all go?" The VCGs seem to leak a little bit, but it's nothing like when I got the car. It smoked as soon as it warmed up and you could smell it burning. Nothing like that in the last 6,000 miles.
I guess I'll take the blame for not checking the oil enough in a car I like beating on, instead of trying to pass it off to previous events out of my control. I'm paying for it either way. Not the end of the world considering the car was free.
I last got the oil changed at ~66k and was due at 71,850. I'm currently at 71,245, so I was 600 miles away from a 5k interval. If the oil wasn't low after changing it, it's certainly low now. It doesn't even fully pass the twist at the bottom of the dipstick. The "side stripe" of oil running up the side of the dipstick was most likely just some drippings from pulling the dipstick out of the tube. It's not present now. But today the dipstick had some metal shavings, which hasn't happened before, but I've already confirmed piston play.
I think I'll go back to the "excessive" 3-4k intervals.
Now the question (which probably won't be answered) is "where did it all go?" The VCGs seem to leak a little bit, but it's nothing like when I got the car. It smoked as soon as it warmed up and you could smell it burning. Nothing like that in the last 6,000 miles.
I guess I'll take the blame for not checking the oil enough in a car I like beating on, instead of trying to pass it off to previous events out of my control. I'm paying for it either way. Not the end of the world considering the car was free.
FDR
Dedicated LVC Member
I guess it's about time I posted those tips for reaching all the bolts I was going to past "next week" ... 3 months ago. I may be too late to help anyone being 15 years since the car came out, but whatever. There are still first time LS owners. This is on my Gen 1 V8. There are other writeups and a tech article, but this is meant as a tips, tricks and hints type writeup
If this is your first time, I recommend doing the passenger side first to build confidence, then the driver side because it's a bit harder. If this is not your first time, do the driver side first to get the BS out of the way. One thing to note is most of the bolts are retained in sleeves that are in turn retained by the gaskets. I believe only the two lower firewall-side bolts are not retained. Or uppers. Mine might be mixed up. Reach in and pull; it'll be obvious. Note "remove" usually just means "unscrew until no longer threaded"
Step one: take things off. Wiper arms, cowls, engine cover, headlight cover, shock tower covers, and the canister bolted to the driver shock tower, intake tube from filter to throttle body. The uncovered shock tower brace also provides a nice grab/lean point. Depressurize the fuel line and use the quick disconnect tool to disconnect the fuel line. Remove the shock tower bolt of the fan fluid reservoir.
You'll want the extra access to those back bolts in particular. Yes, you can get away with fewer items removed, but this relieves a bit of stress and complication of 2 u-joints, several extensions, and seeing with your hands
Step 2: disassemble the engine
Step 3. Reassemble.
Here's all I used once that stuff was removed.
8mm normal socket,
8mm deep socket (both 1/4" drive),
1/4" u joint, and extensions.
3/8-1/4 adapter depending on wrench.
I don't remember what the factory coil cover and COP bolts were.
This picture has everything I used for the actual VC bolts, but not pictured:
normal non-torquing ratchet,
fuel line quick disconnect tool,
screwdrivers,
socket for windshield wipers,
beer,
more extensions
1/4" drive screwdriver handle (just for some speed)
Step 2: remove COP covers and COPs
step 3: remove the obvious bolts
step 4: remove the complicated bolts
PASSENGER SIDE
The lower bolt between the forward spark plug and timing chain is a bit tricky. Just rotate the fan fluid reservoir around it;s other bolt and you can get straight extensions through like this
For the lower firewall-end screw, use (in order) shallow 8mm socket, u-joint, ~2ft of extensions, wrench. Stick it between that massive wiring harness and the insulation jacket around your cabin air intake
The upper-rear bolt may be a little tricky due to the plastic harness shield, but the same socket-ujoint-fewer extensions combo should work.
To remove the valve covers once all bolts are removed, just lift up in line with the spark plugs and slide forward towards the radiator. It may stick a bit and take some light prying with a flathead screwdriver. Move it slowly because the screws will catch on the camshaft braces.
Reassembly is reverse, nothing particularly special
DRIVER SIDE
Did you take this thing off?
Do like Ke$ha and take it off.
Remove obvious bolts
The dipstick has a flange that is attached to one of the VC bolts via stud/nut. Remove the dipstick, remove the nut, then pull the entire dipstick tube up. Or, recall how difficult it was to reinstall, and just cut the flange in a way that it hooks the stud, but can still be slid around it and off
Wide shot, but you can see the flange is now a J-shape
Another
Remove stud with deep socket
Next, between cylinders6 and 7 (so the middle of the bank) on the lower side, shove the straight extensions between these two brake lines, between the shock tower and brake reservoir
Get the lower rear firewall bolt the same way you got the corresponding bolt on the passenger side: socket, joint, exteeeeeeeensions. Stick it all between the two solid brake lines coming off the brake booster
To get the upper, just socket and exteeeensions through where the cowl was. My finger points to where the socket/bolt actually are (that little blue)
This VC is harder to remove due to there being more things in the way. Twist the oil fill spout and remove it. It may help to unclip the throttle cable from it's locating bracket in the middle of the car. Move the VC slowly up, then forward. When it gets stuck, try rotating it end to end to see where it's caught. Most of the time, it's a bolt caught on a camshaft part. Just reach under and lift the bolt.
Assembly is mostly the same, in reverse. For the last bolt I showed, you can stuff some paper or paper towel in the socket, followed by the bolt, and it will stay in the socket pretty well.
This is also a good time to replace your cabin filter.
Hope I helped someone. Please consider the environment before quoting this entire post.
If this is your first time, I recommend doing the passenger side first to build confidence, then the driver side because it's a bit harder. If this is not your first time, do the driver side first to get the BS out of the way. One thing to note is most of the bolts are retained in sleeves that are in turn retained by the gaskets. I believe only the two lower firewall-side bolts are not retained. Or uppers. Mine might be mixed up. Reach in and pull; it'll be obvious. Note "remove" usually just means "unscrew until no longer threaded"
Step one: take things off. Wiper arms, cowls, engine cover, headlight cover, shock tower covers, and the canister bolted to the driver shock tower, intake tube from filter to throttle body. The uncovered shock tower brace also provides a nice grab/lean point. Depressurize the fuel line and use the quick disconnect tool to disconnect the fuel line. Remove the shock tower bolt of the fan fluid reservoir.
You'll want the extra access to those back bolts in particular. Yes, you can get away with fewer items removed, but this relieves a bit of stress and complication of 2 u-joints, several extensions, and seeing with your hands
Step 2: disassemble the engine
Step 3. Reassemble.
Here's all I used once that stuff was removed.
8mm normal socket,
8mm deep socket (both 1/4" drive),
1/4" u joint, and extensions.
3/8-1/4 adapter depending on wrench.
I don't remember what the factory coil cover and COP bolts were.
This picture has everything I used for the actual VC bolts, but not pictured:
normal non-torquing ratchet,
fuel line quick disconnect tool,
screwdrivers,
socket for windshield wipers,
beer,
more extensions
1/4" drive screwdriver handle (just for some speed)
Step 2: remove COP covers and COPs
step 3: remove the obvious bolts
step 4: remove the complicated bolts
PASSENGER SIDE
The lower bolt between the forward spark plug and timing chain is a bit tricky. Just rotate the fan fluid reservoir around it;s other bolt and you can get straight extensions through like this
For the lower firewall-end screw, use (in order) shallow 8mm socket, u-joint, ~2ft of extensions, wrench. Stick it between that massive wiring harness and the insulation jacket around your cabin air intake
The upper-rear bolt may be a little tricky due to the plastic harness shield, but the same socket-ujoint-fewer extensions combo should work.
To remove the valve covers once all bolts are removed, just lift up in line with the spark plugs and slide forward towards the radiator. It may stick a bit and take some light prying with a flathead screwdriver. Move it slowly because the screws will catch on the camshaft braces.
Reassembly is reverse, nothing particularly special
DRIVER SIDE
Did you take this thing off?
Do like Ke$ha and take it off.
Remove obvious bolts
The dipstick has a flange that is attached to one of the VC bolts via stud/nut. Remove the dipstick, remove the nut, then pull the entire dipstick tube up. Or, recall how difficult it was to reinstall, and just cut the flange in a way that it hooks the stud, but can still be slid around it and off
Wide shot, but you can see the flange is now a J-shape
Another
Remove stud with deep socket
Next, between cylinders6 and 7 (so the middle of the bank) on the lower side, shove the straight extensions between these two brake lines, between the shock tower and brake reservoir
Get the lower rear firewall bolt the same way you got the corresponding bolt on the passenger side: socket, joint, exteeeeeeeensions. Stick it all between the two solid brake lines coming off the brake booster
To get the upper, just socket and exteeeensions through where the cowl was. My finger points to where the socket/bolt actually are (that little blue)
This VC is harder to remove due to there being more things in the way. Twist the oil fill spout and remove it. It may help to unclip the throttle cable from it's locating bracket in the middle of the car. Move the VC slowly up, then forward. When it gets stuck, try rotating it end to end to see where it's caught. Most of the time, it's a bolt caught on a camshaft part. Just reach under and lift the bolt.
Assembly is mostly the same, in reverse. For the last bolt I showed, you can stuff some paper or paper towel in the socket, followed by the bolt, and it will stay in the socket pretty well.
This is also a good time to replace your cabin filter.
Hope I helped someone. Please consider the environment before quoting this entire post.