New engine knocking... so blown.

torque converter goes on the trans output shaft, flexplate gets bolted to the crank. they don't get bolted together until the trans is in the vehicle or it could be misaligned. this is what i've always heard but when it comes to transmissions i'm more familiar with chevys than xjs. I've always done it that way and haven't had a problem, but i know people who have ha problems bolting the converter to the flexplate then putting the trans in the vehicle. not sure how you went about it just my personal experience.

did you try the pipe method to pinpoint the location of the noise?
 
Oh I see what you mean. No the torque converter stayed on the trans during the whole swap. I've done it the other way, remove the trans with the converter still on the engine, and it was WAY more work. Removing the 4 flexplate bolts is much easier.

I got a few more opinions today. 2 engine guys say it's probably a bearing, but to run it (they figure it's a Jeep, F-it). I don't really like that mentality but they do know there stuff. Another engine guy thinks it's valve-train related. Cam, lifter, or pushrod. I took off the valve cover and made sure all the cap bolts are tight, they are. I don't really know what to look for up there, but damn it sure was clean and everything looked fine.

I'm in the process of taking the oil pan back off right now. I'm gonna loosen up the caps and inspect each bearing. To me the oil looks totally normal. Decently dark in a pan, but see-through when draining. No noticable chunks or particles. If you have a SUPER bright led flashlight and hold it RIGHT up to the oil, you can see a little bit of pearl/metallic sheen to it. But I'm talking like microns. Not visible at a glance whatsoever. Looks like more downtime is on the horizon :(
 
Wouldn't oil be squriting everywhere? If not then hell yea I'll do it that sounds cool lol. Tayln I tried to the best of my abilities the narrow down the sound to a specific area, but I'm just too inexperienced to differentiate between what's normal and what's problematic. Everything sounds the same to me. The noise gets a little louder or quieter, but not to the point where I could say oh it's coming from around this area. As of now, all I know is it's from the back potion of the block. Whether that's cylinder 3, 4, 5, 6, I can't tell.

Glad I pulled the pan again, it must have been late and I must been delirious not to notice the metal in it. Nothing excessive (I don't think), but definitely some gold dust collecting around the drain area, and two silver 'fingernail' looking slivers of metal. This got me a little worried. I pulled connecting rod caps number 1 and 6 (they were BDC) and the bearings still look brand new.

The cam also looks hardly broken in. only worn in the middle 1/3 portion I'd say, and all of the lobes look exactly the same. I'll get some pics tomorrow when it's light out.
 
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Here's what's in the bottom of the pan. Not a ton of metal, but it's there.
DSCN1981.jpg


The oil. Looks like oil... But you can see some of the dust around the edge of the puddle.
DSCN1983.jpg


On of the ORIGINAL bearings. Obviously worn through to the copper and loaded unevenly.
DSCN1984.jpg


Compared to my new bearings that look, well, new.
Rod cap #1
DSCN1985.jpg

Rod cap #6
DSCN1996.jpg


The three metal slivers that I found.
DSCN2000.jpg
 
those slivers are almost definately cam bearing slivers, unless they are hard and brittle, then they could be pieces of a piston coming apart.
 
Nope they're soft and can be crushed in your fingers. Man this is just what I wanna hear lol. The thing that I find weird is that it is 100% non-existent on a cold start. Takes about 5 minutes until the temp is right around 210 for it to be at it's loudest. But there's a good 90 seconds where the engine sounds completely healthy. Is there any way I could switch to a thicker oil? I've already got 10w30 in there....
 
is 10w30 what you broke the engine in with? and I hate to say it but once the cam bearings start to come apart you're starting to risk tearing up the journals on the cam itself. I'm sure its going to be a pain in the ass but if it were me I'd yank the front header panel and radiator out of the jeep and pull the cam, then you should be able to see the bearing surfaces enough by looking up from underneath with a flash light and a mirror.

I'd rather go through the hassle and not find anything than just dump thicker oil in there to cover up a noise. I'd like to see what some more people think of those slivers though, so don't go pulling it apart yet. Have you asked your hot rod buddies to take a look at them?
 
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GrimmJeeper said:
is 10w30 what you broke the engine in with? and I hate to say it but once the cam bearings start to come apart you're starting to risk tearing up the journals on the cam itself. I'm sure its going to be a pain in the ass but if it were me I'd yank the front header panel and radiator out of the jeep and pull the cam, then you should be able to see the bearing surfaces enough by looking up from underneath with a flash light and a mirror.

I'd rather go through the hassle and not find anything than just dump thicker oil in there to cover up a noise. I'd like to see what some more people think of those slivers though, so don't go pulling it apart yet. Have you asked your hot rod buddies to take a look at them?
Click to expand...

just quoting this so its on the next page, i was editing the post while you were relpying.
 
actually now that I think about it I don't know if there is room to get the cam out with the front cross brace there. I've never actually done it that way so I can't say for sure.
 
I think if I dropped the trans ALL the way down and totally stressed the motor mounts, the front cover and cam MIGHT be able to come out. I'm gonna button it back up for now so it's not disabled in the driveway. Then I can plan the surgery all over again :( It's not my only source of transportation but I'd love to have it back on the road after being down for 2+ weeks. I'm gonna try to get ahold of one of my old teachers, he knew more about engines than anyone I've ever come across. I'll report back if I find anything new.

On a side note: Didn't this happen to Talyn? I remember when he got his stroker running his cam got wiped or his bearings came apart, I don't quite recall the details.
 
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Man just when I was ready to put it all back together. I'm taking apart the last two rod bearings thinking this is such a waste of time, they're all gonna look the same. Wrong. Number 5 is severely scored up. Not only can you catch your fingernail on it, but you can feel it with the skin on your fingertip. Easily a few hundredth's deep. I'm praying you guys will say this could be a source of noise. The pictures might be kinda blurry and don't really show the depth, but you should get the idea.

IMG_9367.jpg

IMG_9373.jpg

IMG_9374.jpg
 
I don't think those scratches would be the source of the knocking noise. however they do appear to be a bit deep and I would replace that bearing. What does the crank journal look like? What about your cam bearings? Can you see any material sticking out? The harmonic balancer, cover and cam can be removed with out messing with the engine mounts or transmission mounts. Remove the rad and support the ac condenser on a block or something. You can replace the bearings that way as well except the rear one.
 
I know you did your build in a storage unit, did you have to rent/buy the tool to install the bearings or make something up? I used a really nice one from school before but don't think I'll have access to it this time around.
 
Alright got it all back together for the time being. Knock is still there, still very loud. I'm gonna get a video of it pretty soon.

Strange thing though, you guys were saying disable the cylinders one at a time. I finally got some quiet without rain etc. I took the belt off so I could hear the motor without the fans, water pump, steering etc. I pulled the injector connectors one at a time. You could distinctly hear each miss, but the knock didn't change AT ALL. Not one bit.
 
What did the thrust bearing look like on the crank?
 
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