Metal shavings (pictures) motor knocking
#1
Junior Member
Thread Starter
Join Date: Nov 2013
Location: North East Georgia
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Grand Cherokee
Engine: 4.0L STRAIGHT 6!!!
Metal shavings (pictures) motor knocking
97 grand cherokee 4.0 4x4
does anyone have any ideas what these metal shavings could be from?. They are in the oil pan. They kind of have a copper color to them.
I rotated the harmonic balancer and could not see anything that appears to have damage. The cylinder walls for the most part look ok. I feel like this metal is from the actual pistons or at least the arms under them that connect to the crank shaft and again, I cant see any damage any where.
A couple of weekends ago I pulled the cylinder head off replacing the lifters, head gasket, push rods and valve springs. I put it back together and it fired up on the first crank. I drove it for 2 days just to work and back. My commute is 1hr long. By the time I reached work my temp gauge had climbed to about 220. It started climbing around the last 15min of my drive. During my lunch break on the second day I noticed what sounded like a knocking. The morning of the second day we pulled the valve cover and I tightened down the rocker arm bolts. When I left for lunch is when I heard the knocking. After work on the second day we opened up the valve cover again and I started to adjust the rocker arm bolts. The knocking sound went away. I got onto the highway and the knocking was right there with me. I got home an hr later the motor was knocking while at idle. I let the jeep cool down and removed the valve cover agaaaaaaaaaiiiiinnnnnn. I started it and adjusted the bolts on the rocker arms again and the knocking went away. As soon as I tried to drive up the street you could hear the knocking again. So I parked it and today I finally was able to take off the oil pan and the metal shavings I found in it are pictured below.
Since I cant really see all the cylinders from under the jeep Im going to pull the cylinder head this weekend and will pull out all the pistons to give a visual inspection.
Im curious to your opinions. Im hoping my crank isn't damaged as I feel everything else is more easily replaceable.
Thoughts, opinions and roastings are welcome
Thanks
does anyone have any ideas what these metal shavings could be from?. They are in the oil pan. They kind of have a copper color to them.
I rotated the harmonic balancer and could not see anything that appears to have damage. The cylinder walls for the most part look ok. I feel like this metal is from the actual pistons or at least the arms under them that connect to the crank shaft and again, I cant see any damage any where.
A couple of weekends ago I pulled the cylinder head off replacing the lifters, head gasket, push rods and valve springs. I put it back together and it fired up on the first crank. I drove it for 2 days just to work and back. My commute is 1hr long. By the time I reached work my temp gauge had climbed to about 220. It started climbing around the last 15min of my drive. During my lunch break on the second day I noticed what sounded like a knocking. The morning of the second day we pulled the valve cover and I tightened down the rocker arm bolts. When I left for lunch is when I heard the knocking. After work on the second day we opened up the valve cover again and I started to adjust the rocker arm bolts. The knocking sound went away. I got onto the highway and the knocking was right there with me. I got home an hr later the motor was knocking while at idle. I let the jeep cool down and removed the valve cover agaaaaaaaaaiiiiinnnnnn. I started it and adjusted the bolts on the rocker arms again and the knocking went away. As soon as I tried to drive up the street you could hear the knocking again. So I parked it and today I finally was able to take off the oil pan and the metal shavings I found in it are pictured below.
Since I cant really see all the cylinders from under the jeep Im going to pull the cylinder head this weekend and will pull out all the pistons to give a visual inspection.
Im curious to your opinions. Im hoping my crank isn't damaged as I feel everything else is more easily replaceable.
Thoughts, opinions and roastings are welcome
Thanks
#3
CF Veteran
Good one. First off there is no 'adjustment' on the rocker arms, you torque them to spec and that's it. So why you keep doing that scares me. From what you describe Im thinking there is a problem with the head sealing. Since you pulled the head and replaces some stuff..the debris in the pan could be anything and not related to the knockinig at all. I think the knock is from you not replacing the head gasket, not replacing the head bolts, not cleaning the block and head mating surfaces, not checking the head for cracks or warpage (they are all warped a bit when they come off) or not following the proper torque sequence with the head bolts, including the special sealing and torque of the head bold in the right front, which could allow coolant into the cylinder.
I would lay my hands on a radiator pressure tester and use it to see if there is a leak in the cooling system, I think you're pulling the head again for a coolant leak that causes the knock
I would lay my hands on a radiator pressure tester and use it to see if there is a leak in the cooling system, I think you're pulling the head again for a coolant leak that causes the knock
#4
Old fart with a wrench
Dude! Before you put it back together, pull all the bearing caps off and inspect the bearings, mains as well as rods. I think you have a problem. Be sure to re-torque them properly before you do anything else.
#5
CF Veteran
Bye bye rod bearing. Nothing good from those pictures. If you look at the rod caps, I bet you can find one that is extra dark and has a blueish tint to it. That will be the bearing that spun.
#6
Junior Member
Thread Starter
Join Date: Nov 2013
Location: North East Georgia
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Grand Cherokee
Engine: 4.0L STRAIGHT 6!!!
Good one. First off there is no 'adjustment' on the rocker arms, you torque them to spec and that's it. So why you keep doing that scares me. From what you describe Im thinking there is a problem with the head sealing. Since you pulled the head and replaces some stuff..the debris in the pan could be anything and not related to the knockinig at all. I think the knock is from you not replacing the head gasket, not replacing the head bolts, not cleaning the block and head mating surfaces, not checking the head for cracks or warpage (they are all warped a bit when they come off) or not following the proper torque sequence with the head bolts, including the special sealing and torque of the head bold in the right front, which could allow coolant into the cylinder.
I would lay my hands on a radiator pressure tester and use it to see if there is a leak in the cooling system, I think you're pulling the head again for a coolant leak that causes the knock
I would lay my hands on a radiator pressure tester and use it to see if there is a leak in the cooling system, I think you're pulling the head again for a coolant leak that causes the knock
Damn son! I didn't know you needed all the details!
I did sneeze a couple of times, stopped to change into shoes from sandles gave my wife a couple of odd looks and took a couple of tokes.
However I did change the head gasket as mentioned above and of course all surfaces were cleaned very well. My brother inlaw was surprised I caught the info on replacing the head bolts. My set was $20 and his for his dodge they are well over $1100. So there was a bunch of conversation about those. #11 per torq chart said 100flbs with thread sealer and of course following the special pattern on the chart. No visible cracks or warpage when the head was off.
Now with all the info I took in about this motor I had a hand full of people throwing their opinions and past experience at me so adjusting the rocker arms may sound bad to you and very well could be but when you have multiple people telling you that you have to do this and that (you seem firmilar with that) you tend to take suggestions to see if it fixes the problem.
Another suggestion I'm going to act on is the radiator thing you mentioned just to say it's been done despite my system not losing fluid and hasn't been in the past years.
The mechanic I took it to for a full diag report about a month ago specifically told me the coolant system was the only thing that wasn't wrong with the jeep.
But, my rad is pretty beat up. water pump and thermostat are about a year old.
All in all I wish I had some audio for but I don't. The timing chain and sprockets were changed when I changed everything else and when the hood is open you can almost hear the knocking coming from from around 2 or 3 as the motor gets gas.
I have never claimed to be smart but considering what I see via through the oil pan there isn't much that could produce the metal that's in my oil pan in the picture.
If I'm ever getting roasted on tv for being infamous and a dumb *** you will be the first guest!
I'll be checking on the rad soon just for further maintenance, thanks
#7
Junior Member
Thread Starter
Join Date: Nov 2013
Location: North East Georgia
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Grand Cherokee
Engine: 4.0L STRAIGHT 6!!!
I know I have a problem here, it looks like I've been using my oil pan to pan for gold. I was hoping everyone's opinions would be about bearings rather than hearing your cylinder walls are trashed or you gouged your crank.
These fixes don't scare me so I'm ready for anything except pulling the motor out of the jeep. I do not want to do that.
Will I be able to change all crank bearings and pull arm bearings with out removing the block from the mounts? I'm I missing any bearings? Will I be able to pull my crank out of the block through the bottom once I remove all the arms and bearing caps on the crank?
Trending Topics
#8
Junior Member
Thread Starter
Join Date: Nov 2013
Location: North East Georgia
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Grand Cherokee
Engine: 4.0L STRAIGHT 6!!!
Thanks for the input man. Aside for what's in the picture, I should be ok once certain parts are replaced right?
#10
CF Veteran
Yes and no. If it spun a bearing, the engine is coming all the way apart. It will need at a minimum the crank to be turned .010" and 1 rod. If the bearing hasnt spun yet, well you could get lucky but I still think it will need a new rod. Just depends on how hot that bearing got. If it got hot enough, it would have ovaled the big end of the rod a bit.
#11
Junior Member
Thread Starter
Join Date: Nov 2013
Location: North East Georgia
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Grand Cherokee
Engine: 4.0L STRAIGHT 6!!!
Yes and no. If it spun a bearing, the engine is coming all the way apart. It will need at a minimum the crank to be turned .010" and 1 rod. If the bearing hasnt spun yet, well you could get lucky but I still think it will need a new rod. Just depends on how hot that bearing got. If it got hot enough, it would have ovaled the big end of the rod a bit.
#12
CF Veteran
Technically yes. But I dont think it will drop out if the flexplate is still on there. So you would need to remove the trans... Its one or the other.
#13
Old fart with a wrench
You can remove the bellhousing bolts and slide the trans back a couple of inches, but on a 4wd it's difficult to do that.
#14
Junior Member
Thread Starter
Join Date: Nov 2013
Location: North East Georgia
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1997
Model: Grand Cherokee
Engine: 4.0L STRAIGHT 6!!!
If I were to maybe unbolt the transmission mount ( i have a new one to put on ) do you think I would get enough play to move the transmission back enough to get out the crank?
#15
Old fart with a wrench
Probably. You only need enough room for the flexplate to clear the converter hub. You can install a couple of long bolts in the bellhousing to support it. Use a jack under the trans to balance the engine as well.
Caution! That crank is heavy! Take the spark plugs out so you can push the pistons and rods up out of the way. Be careful not to nick the crank with the rod bolts when you put it back in.
Caution! That crank is heavy! Take the spark plugs out so you can push the pistons and rods up out of the way. Be careful not to nick the crank with the rod bolts when you put it back in.
Last edited by dave1123; 04-12-2019 at 02:20 PM.