Turns out my 1994 4Runner has a bad rod bearing, among other things

Making good progress. That impact wrench sure makes things easier!

I'm having some trouble loosening the propeller shaft, can't use my 2' torque wrench because of lack of space. I soaked it thoroughly with PB Blaster and will try later.

As you can see in the photo, I'm removing the bracket that holds the brake line, as the brake line is in my way for getting a socket around the castle nut. Once that's done I ought to have the castle nut off pretty quickly. Am I going to need a way of pushing the arm down or something to get clear of that bolt?
 

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The top arm is tied to the torsion bar, so before you pull anything off, jack the control arms as high as you can, then stick something thick between the top control arm and the bumpstop to shim it. Then when you unbolt the ball joints, the lower arm will just fall away.
 
Wow, 10 days since my last post. I was traveling all last week and the 4runner just sat waiting. Today I finally got the driver-side steering knuckle off and got the bad CV axle out! Finishing the other side should be pretty easy now and then it's time to drop the diff and oil pan. Hopefully I can swing it by this weekend.

 
Success! Diff dropped (literally), despite using the jack. Next time I'll take it off with the support bar. Luckily it didn't fall very far and looks OK. Oil draining now.
 

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Success!

Success! Got the rod bearings out. A few of them look a bit rough around the edges, but none of them wore down to the copper. I just need to measure the crankshaft journals with some calipers to double-check and then time to order some new bearings. Makes me worry maybe the main bearing is going or something though. Need to figure out how to check that.

EDIT: OK, I need to get some plastigauge and check my rod bearing clearance.

QUESTION: Can I take off the main bearing cap while the engine is in the car? Will the crankshaft stay in place? I guess if it will then I can't check the upper bearings anyway. Hm.
 

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Success! Got the rod bearings out. A few of them look a bit rough around the edges, but none of them wore down to the copper. I just need to measure the crankshaft journals with some calipers to double-check and then time to order some new bearings. Makes me worry maybe the main bearing is going or something though. Need to figure out how to check that.

EDIT: OK, I need to get some plastigauge and check my rod bearing clearance.

QUESTION: Can I take off the main bearing cap while the engine is in the car? Will the crankshaft stay in place? I guess if it will then I can't check the upper bearings anyway. Hm.

yes, you can pull the mains. just do one at a time.

also, you CAN get the upper bearing out. loosen ALL the caps, but only remove ONE. then use something like a thin plastic ruler, or even a wood shim(anything but metal) to push against the bearing. it will spin around toward the bottom and fall out. installation of the new bearings is just as easy.

oil it up, stick it in place, and spin it around until its on top.
 
yes, you can pull the mains. just do one at a time.

also, you CAN get the upper bearing out. loosen ALL the caps, but only remove ONE. then use something like a thin plastic ruler, or even a wood shim(anything but metal) to push against the bearing. it will spin around toward the bottom and fall out. installation of the new bearings is just as easy.

oil it up, stick it in place, and spin it around until its on top.

Awesome, thanks!
 
yes, you can pull the mains. just do one at a time.

Hm, I can't get the main cap off. Seems to be stuck on a flange at the back of the engine. And now I'm quite worried it is in fact the main bearings. A couple of the main cap bolts came out with some nasty burnt-smelling very black oil on them. I don't know if that's just sludge or indicates a spun bearing, I'm new at this.

EDIT: Seems I'm boned. :( Yotatech 3vz-e main bearing cap stuck I am NOT grinding it off like that guy proposed to do.

QUESTION: Any other suggestions? Is there any way to tell whether it's a main bearing? The crankshaft doesn't seem to have any play, not that I expect it would with the wimpy forces I can exert on it.
 
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Hm, I can't get the main cap off. Seems to be stuck on a flange at the back of the engine. And now I'm quite worried it is in fact the main bearings. A couple of the main cap bolts came out with some nasty burnt-smelling very black oil on them. I don't know if that's just sludge or indicates a spun bearing, I'm new at this.

EDIT: Seems I'm boned. :( Yotatech 3vz-e main bearing cap stuck I am NOT grinding it off like that guy proposed to do.

QUESTION: Any other suggestions? Is there any way to tell whether it's a main bearing? The crankshaft doesn't seem to have any play, not that I expect it would with the wimpy forces I can exert on it.
can you spin the engine so the journal is out of the way, and tip the cap in towards the center of the motor?



mind you, im going off the pics in that thread you just posted. if you can take better pics of your exact situation, that might help.


also, the burnt oil on the bolts is normal. that oil sits in there and NEVER moves, its bound to get burnt.
 
can you spin the engine so the journal is out of the way, and tip the cap in towards the center of the motor?

Hm... I don't think so? I could try and get some pictures but I don't think I can show anything more than that thread does. Basically the thing can't tilt enough to come out because in back it's blocked by the rear main oil seal flange, and in front it's too tall to rotate out with the back held up.

It's looking like I'm going to have to convince myself it's the rod bearings that were making noise, or drop the transmission and/or pull out the engine. And here I thought I was about done. :(

the burnt oil on the bolts is normal. that oil sits in there and NEVER moves, its bound to get burnt.

Makes sense, thanks. God they stink.
 
Hm... I don't think so? I could try and get some pictures but I don't think I can show anything more than that thread does. Basically the thing can't tilt enough to come out because in back it's blocked by the rear main oil seal flange, and in front it's too tall to rotate out with the back held up.

It's looking like I'm going to have to convince myself it's the rod bearings that were making noise, or drop the transmission and/or pull out the engine. And here I thought I was about done. :(



Makes sense, thanks. God they stink.

well, if you absolutely cant get the rear cap off, just leave it, and change the rest.

altho, and I say this without seeing it in person...I bet that cap can be worked out of there.

it wont want to move at all, since its suctioned in place with oil. once you get it moving, or rather IF you get it moving, you may be able to rock it out of position.
 
well, if you absolutely cant get the rear cap off, just leave it, and change the rest.

altho, and I say this without seeing it in person...I bet that cap can be worked out of there.

it wont want to move at all, since its suctioned in place with oil. once you get it moving, or rather IF you get it moving, you may be able to rock it out of position.

Wait, I just read your post about this from the other thread on the 8th. You mean take out the bearings with the cap still in there?
 
Wait, I just read your post about this from the other thread on the 8th. You mean take out the bearings with the cap still in there?

I doubt you would be able to do that. it would have to drop down significantly.
if you could get them out without doing any damage...
 
I doubt you would be able to do that. it would have to drop down significantly.
if you could get them out without doing any damage...

Yeah ok, it sounded kind of crazy to me. :) At this point it's easy enough to replace the rod bearings, close it back up, and see if the knock is gone. I should be able to do that on jack stands with the front end disassembled, right? Just make sure the parking brake stays on and the transmission is in neutral? Once I got the front end disassembled it was actually a pretty quick job to get to the rod bearings.
 
Yeah ok, it sounded kind of crazy to me. :) At this point it's easy enough to replace the rod bearings, close it back up, and see if the knock is gone. I should be able to do that on jack stands with the front end disassembled, right? Just make sure the parking brake stays on and the transmission is in neutral? Once I got the front end disassembled it was actually a pretty quick job to get to the rod bearings.

neutral is fine, park is even better.

also, as I said above, go ahead and change the other 4 mains, no reason not to, since you're in there already.

make sure and oil all the bearings good when you put them in, and TORQUE all the caps to spec.
 

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