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14.1 @ 100mph N/A
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Discussion Starter · #1 · (Edited)
These may already be available, but this is my real-life method for changing rod bearings. It's easy enough for anyone to do. The bearings cost $72 at a dealership ( partznet.com ) and are worth changing on any car with over 100k miles. I'd recommend changing the 120k tune-up to 100k and doing the rod bearings and oil pump at the same time.

SIMPLE INSTRUCTIONS FOR CHANGING ROD BEARINGS:

0) Purchase a bag of common sense... you'll need it if any problems arise and 3si is down.

1) Jack up the car... just jacking up the front will do. Get it up as high as you can(I use 22" jack stands).

2) Drain the oil.

3) (for N/A) Remove the 4 front pipe nuts from the manifolds. 19mm or 3/4" will work. I used a breaker bar and a can of WD-40 and they came right off.

(for TT) Dunno about a TT, but it'll be self-explanatory which bolts/nuts to remove to get the downpipe off.

both TT and N/A Remove frontpipe/downpipe from cat/test pipe(14mm), and shove the front pipe/down pipe out of your way with it still attached to the hanger.

4) (for TT)[/.b] drain and remove the transfer case

5) (for TT) remove the turbocharger oil return lines from the oil pan.

6) Remove the starter(14mm).

7) Remove the 2 gold-colored brackets that attach to the bottom of the tranny and the side of the engine. 17mm and 14mm. Remove the thin metal plate that covers the bottom of the tranny bellhousing while you're at it... 2 10mm bolts.

8) Remove the driver's side crossmember, leaving the frontmost bolt attached but loose. There are 5 14mm bolts that you will remove. Swing it out of the way of the oil pan.

9) Undo the 10mm oil pan bolts. DO NOT allow the bolts that are near the bellhousing to fall into it. It won't cause any damage, but lets try not to let them fall in anyways.

10) Use a flat pry bar to pry off the oil pan. Don't be afraid to get rough with it. You may need to use a putty knife to start a slot to insert the pry bar if your bar is too thick. You'll need to pry on the corner near where the starter goes. Once the pan pops off a bit, it'll come off easily. You WILL bend the pan, so straighten it with a hammer later.

11) Remove the oil pump pickup tube(12mm, I believe).

12) ***DO NOT let oil drip in your eyes!***Turn the crank with a 1/2" drive ratchet inserted into the crank pulley bolt(no socket). Turn it until the 2 rod caps furthest towards the tranny are both accessible. You'll see 4 nuts near each other.

13) Undo the 2 14mm nuts on the #6(closest to the tranny) rod cap. Wiggle the cap until it comes off... you can tap the studs with a small hammer if necessary.

14) Snip off a 1/2" long piece of green Plastigauge and stick it on the crank where the bearing used to sit. Reinstall the rod cap(WITH the old bearing still in it) and tighten it bit by bit, one side then the other, until you reach a final torque of 38 lb/ft. Now remove the cap and hold the Plastigauge package up to the squished plastic and see what your clearance is. It's most likely still in spec, but worn nonetheless.

15) Scrape the plastic off the crank with your fingernail and maybe some WD-40.

16) Pop the old bearing out of the lower rod cap and insert the new one. Make sure it seats in tightly and there's no grit or assembly lube/oil between the bearing and the cap. Lube up the side that will contact the crankshaft with oil or assembly lube(I use oil).

17) Push up the piston by pushing on the rod bolts until it slides up a tiny bit. Use a screwdriver to push the upper bearing out of its position(coat the tip with silicone and let it dry if you're clumsy and don't want to scratch the crank).

18) Lube up the crank side of the new bearing and slide it in to position by placing it on the oily crank and sliding it, then gently pulling down on the rod/piston assembly until the bearing is seated fully it its position... you'll get the hang of it quickly, so don't be intimidated by this step.

19) Install the rod cap(there is a little circle stamped into the rod cap telling you which way it faces, so make sure you install it correctly) and tighten it bit by bit, one side at a time, until 38 lb/ft. Remove it and Plastigauge to make sure you're in spec. Unless your crank is really worn to hell, you'll be back to the minimum spec(.0008 [or .001 on the Plastigauge package]).

20) Scrape off the Plastigauge and reinstall the rod cap... torque it slowly and PRECISELY to 38 lb/ft.

21) Do the #5 bearing(don't worry about Plastigauging it, or any of the others, unless the crank looks damaged), then turn the crank until #3 and #4 are accessible and keep repeating the process until you have all 6 done.

22) Install the oil pump pickup tube... don't overtighten it.

23) REMOVE THE DIPSTICK. It will get bent if you snag it on the oil pan during installation.

24) Put a layer of Ultra Grey silicone on the oil pan flange(after you straighten the flange with a hammer and maybe a piece of 2 x 4 wood). The silicone should be about as deep as a dime is thick and cover the whole flange(screw the service manual recommendations... we don't want leaks).

25) Wipe off the oil pan mounting surface on the engine, and install the pan. Gently thread in all the 10mm bolts and then tighten them to 5 lb/ft(just barely tight). This takes about 10 minutes.

26) Install everything else, making sure not to overtighten anything (except the front pipe/downpipe... we don't want exhaust leaks).

27) Let the car sit for at least 30 minutes before you put oil in it(to let the silicone dry). While you wait, go over everything and make sure you did it all right.

28) Put your new oil in(don't forget to install the dipstick, dipstick).

29) Pull the "ECI" fuse under the hood in the fuse panel on the pass. side. Hold the key turned for about 10 seconds. This helps prime the oil pump. Now reinstall the fuse and start the car up. Drive it gently for the rest of the day to allow the bearings to smooth out and seat well.

30) Keep an eye out for oil drips under the car. If you have a leak, you'll have to pull the pan and redo the silicone. Listen for any strange noises and sniff for any strange smells.


If I forgot anything, let me know and I'll edit the instructions. Thgis job will probably take you about 5 hours, but it's easy. It's just time-consuming.

TOOLS:

1/2" drive breaker bar(at least 18" long)
1/2" drive torque wrench set to 38 lb/ft
1/2" drive long extension(12"+)
1/2" drive short extension(4-6")
1/2" drive sockets: 14mm, 17mm, 19mm

3/8" drive ratchet
3/8" drive long extension(12"+)
3/8" drive sockets: 10mm, 12mm, 14mm, (and 17mm is optional)

Hammer (to bang on the ratchet handles with, and to straighten the oil pan)

Flat pry bar... approx 1' long and 2" wide(you know the type)

Green Plastigauge

Assembly lube or motor oil for lubing the crank side (only) of the bearings.

Ultra Grey silicone sealant from a parts store.

WD-40 or another penetrating oil

Oil

(optional) a few colors of paint or nail polish to mark the crossmember bolts and other if you wish.

Here's a site everyone should read before you tackle this job. It gives a good overview of the benefits and how-to's on bearing replacement:

http://www.babcox.com/editorial/us/us90126.htm
 

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Senior **i.e. OLD** Member
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Drew....I have a stupid question....

You lubricated both sides of the bearing?
Wouldnt that cause the bearing to spin again?
I thought just one side of the bearing was supposed to be lubricated.

Again, Im a rookie, and this maybe a rookie question, but I think this very issue is what got Hans on his first TT.

Bob.
 

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14.1 @ 100mph N/A
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Discussion Starter · #3 ·
I'll re-word the instructions to clarify.

I didn't "lube" the back of the bearings, only the crankshaft sides. I cleaned the rod cap with an oily paper towel to get the grit off of it, so it did indeed have an oily film on it when I installed the bearing... this is safe. There's no need to clean off the rod cap or backs of the bearings with a solvent or anything... just don't gob it up with oil because it can alter your torque readings if a film of oil stays between the bearing and rod/rod cap. If you use assembly lube instead of motor oil, do NOT put any assembly lube on the backs of the bearings where they contact the rod/rod cap. Assembly lube takes too long to dissipate and may cause heat spots on the backs of the bearings. I've rebuilt engines before and I've always cleaned the caps with oil/rags. I've never had any problems with any of my rebuilds.
 

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Thank you.

That makes a TON of sense.
I appreciate you clarifying that.

Bob.
 

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Well done man, I'm impressed... Might have to do this when I pull my engine in a few weeks.
 

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drew...

first off, thanks for the instructions...i'll be doing this when i get back home before i do my 60K and drive my car back to NY

second,
-what is the mitsu part number (to order from partznet)?
-i'm comfortable with my mechanical abilities...if struts and brakes aren't a simple job, you think this is about the same difficulty level (just more time consuming), or a little (lot?) more difficult??

~matt
 

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If you can do a set of struts you should be able to do this... Assuming you can work a torque wrench.... I've seen a lot more people almost kill themselves working with struts/springs, than I have with a rod bearing. :)
 

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14.1 @ 100mph N/A
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Discussion Starter · #8 ·
Here's the search string for the bearings:

Mechanical(enter your year car)
Engine
Pistons, Rings & Bearings
Bearing Set
3000 Gt
$57.54

They list for $73, but apparently Conicelli Mitsu has a good deal on them.

Struts are as hard or harder than this, so have no fear.

Do you only have 60k-ish miles? If so, I'd recommend waiting until 100k to do the bearings unless you're just bored to death and want to get your hands dirty. Like I said before, I'd recommend switching the 60k/120k tune-ups to 50k/100k, and doing the rod bearings and oil pump at 100k.
 

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You break em, we fix em
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I can't believe I am going to be the buzzkill on this one, but...

I REALLY wouldn't recommend this to anyone, and I would wait to see what Drew's (my guess is BAD) long term results are.

You really should NOT do this, I along with many others since the dawn of time have learned the hard way - you typically CANNOT just replace bearings on a whim like this. A lot of times the new ones won't last even as long as the old ones would have since you disturbed things in the bottom end.

First off - there are NUMEROUS technical things to consider if you want a bottom end to last, other than plastigauging one crank pin (can't believe you recommend not plastigauging the rest either...). There are things like surface finish of the rod bore and crank pin, roundness/ovality of the rod bore, straigness of the rod, etc. none of which can be measured with plastigauge. Hell, even the rod bolts really shouldn't be reused in a lot of engines - they only get 1 or 2 torques before they are stretched and useless. You really can't see any of this stuff by eye either. The only real fix to a bottom end problem is to PROPERLY rebuild it - have the crank checked, measured, refinished and have the rods checked, measured, resized, etc. Search the board its got more than a few posts of people that have tried to fix a spun rod bearing by just replacing that one or other budget fixes that have later blown up.

A lot of times I have seen where the original bearings were "worn in" so to speak, and were happy with the crank/rod arrangement. Then during a quickee rebuild new ones were put in and they make the situation worse and do not tolerate the crank surface finish or ovality of the rod or something and fail after barely any miles. Personally wrecked a perfectly good 440 that way...

I hope it works out for you Drew, but I fear that you may find out the hard way like I did that there is no shortcut to rebuilding a bottom end. I certainly would not even consider attempting it unless your car had a problem and you were desperate to get it on the road again for low bucks.
 

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Good overview. Need to emphasize the importantance of not mixing rod end caps. Each rod and associated end cap are a machined matched set. In addition, I recommend carefully cleaning the oil from the rod bolt and nuts, reassemble and torque with "blue locktite". The torque on rod bolts is maintained by a predetermined amount of stretch. Over 100K miles, rod bolts can loose this capability on a retorque and the locktite provides the insurance they will maintain proper torque for another 100K miles.
 

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You break em, we fix em
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I almost forgot - don't forget the possibility of f-up and damage doing the job. We assemble engines here at te plant wearing lint-free gloves for Christ's sake. Now we are advocating that people of possibly dubious mechanical skill pull their oil pan off in their driveway and rebuild the bottom end? One piece of dirt, crud, lint, whatever will wipe a bearing out IMMEDIATELY. One mistake torquing a rod bolt improperly will do the same. By opening the oil pan you are opening yourself up to all kinds of boobery that will ruin your engine. Again - if you have to you may have to, but I certainly wouldn't recommend people do it as "maintenance".
 

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14.1 @ 100mph N/A
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Discussion Starter · #12 ·
moparjim said:
(can't believe you recommend not plastigauging the rest either...)

There's no real need to check all of them unless one journal shows abnormal wear. I recommended checking the #6, which will be the most worn. I checked all of mine and they were all within a few thousandths.

There are things like surface finish of the rod bore and crank pin

...not an issue if the stock bearings were still within spec.

roundness/ovality of the rod bore

again, not an issue if the stock bearings are still in spec, and if there was an ovaled rod/cap you'd be able to tell by the wear pattern on the bearing.

straigness of the rod

Ditto above.

even rod bolts shouldn't be reused on a lot of engines

Our rod bolts are not "elastic" and don't stretch with normal torqueing. The factory-recommended method for checking the rod bolts is to hand thread the nut, and if it snags, you need to remove the bolt and check its length... no too high tech, huh?

The only real fix to a bottom end problem is to PROPERLY rebuild it

Not true. Check AllData for the rod bearing replacement instructons and you'll see that it's just as straightforward as I said it is. It's only a 5 hour dealer-rated job, so it's not brain surgery.

- have the crank checked, measured, refinished and have the rods checked, measured, resized, etc.

We're talking about replacing worn-but-still-in-spec bearings on a relatively good condition engine... not rebuilding a damaged engine. It's perfectly acceptable to replace bearings in an otherwise healthy engine. As a matter of fact, it's common practice.

Search the board its got more than a few posts of people that have tried to fix a spun rod bearing by just replacing that one or other budget fixes that have later blown up.

Once more, if a bearing is spun, the crank will have to be resurfaced, re-treated, and an oversized bearing will have to be installed. If everyting's in spec on your engine, new bearings can ve installed with no other modifications.

A lot of times I have seen where the original bearings were "worn in" so to speak, and were happy with the crank/rod arrangement. Then during a quickee rebuild new ones were put in and they make the situation worse and do not tolerate the crank surface finish or ovality of the rod or something and fail after barely any miles.

I'm not buying the "old bearings are better than new bearings" claim. As long as you do the gentle break in- the new bearings will quickly wear into any pattern of grooves on the crank journal. Go to any engine shop and see if they refinish a crank every time they install new bearings. Any time the old bearings were still in spec and the crank shows no damage, they just throw in new bearings. Hell, the engine doesn't even know the difference as long as the old and new bearings are all in spec.

I hope it works out for you Drew, but I fear that you may find out the hard way like I did that there is no shortcut to rebuilding a bottom end. I certainly would not even consider attempting it unless your car had a problem and you were desperate to get it on the road again for low bucks.

This isn't the fist engine that I've installed new bearings in, and I've never, EVER had any problems even after tens of thousands of miles on the replaced bearings. The key is making sure everything is in spec and there is no abnormal wear on the crank that could damage a bearing. My bearings and crank showed wear, but nothing out of the ordinary for a 135k mile engine, and nothing that would all for machining. What I did is endorsed by Mitsubishi Service as a standard service for worn bearings. Why would Mitsu claim 5 hours labor if the engine had to be pulled and the crank had to be machined? Why would they say "if the nut threads onto the rod bolt easily, the rod bolts are fine" if you need to replace the rod bolts every time you remove them? Why would they say "check the bearings for signs of uneven wear" if you needed to take the rods out and have them checked for ovality at a machine shop? This is the standard process for rod bearing replacement, and it's what any dealership or engine shop would do if you took your engine in and said "I want new rod bearings"

BTW, after 100 miles, I removed the oil pan(because I had an oil leak) and checked the #6 bearing out, and it looked perfect. It had worn in nicely and looked like any fresh bearing on a low mile engine. I now have 1500 miles since the new bearings, and no problems yet. I'll be sure to give updates if anything goes wrong. Hell, I'll pull the pan and check the bearings every week if you want me to. :lol2:
 

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You break em, we fix em
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Very good responses to all my concerns Drew, but remember you are talking about dealers, shops, yourself, or other SKILLED mechanics having possible sucessful results. In this thread you have recommended that people that may have replaced struts and have never built or even seen the inside of an engine perform the work and inspection of the parts. You yourself fell prey to the possible boobery I mentioned by managing to create an oil pan leak in the process...

Anyway, results will definitely vary widely, it may be fine for you but I am just trying to make the point that is risky business in my opinion.

1500 miles is not a lot of miles - I drive 1500 miles every 2 weeks. Let me know how it is after 10K, 20k, 50k miles.

As far as dealers replacing rod bearings, every dealer I have ever been to or heard of doesn't touch the bottom end = they are more than happy to sell you a new short block.
 

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14.1 @ 100mph N/A
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Discussion Starter · #14 ·
moparjim said:
I almost forgot - don't forget the possibility of f-up and damage doing the job. We assemble engines here at te plant wearing lint-free gloves for Christ's sake. Now we are advocating that people of possibly dubious mechanical skill pull their oil pan off in their driveway and rebuild the bottom end? One piece of dirt, crud, lint, whatever will wipe a bearing out IMMEDIATELY. One mistake torquing a rod bolt improperly will do the same. By opening the oil pan you are opening yourself up to all kinds of boobery that will ruin your engine. Again - if you have to you may have to, but I certainly wouldn't recommend people do it as "maintenance".
Lint-free gloves?!?! :lol:

What all do you think gets in the crankcase via the intake, oil cap, oil funnel, etc?

You are REALLY exaggerating about one piece of lint/dirt wiping out a bearing.

You wouldn't believe some of the debris I've found in oil pans with the factory seal on them... silicone chunks, paint chips, metal flakes, threads from stripped drain holes, even "flash" metal flakes from the main caps that broke loose and went for a swim. If the clearances are in spec, no sizeable debris can get between the bearing and crank journal.

The filtration system is there for a reason.

Lets not act like this is a lobotomy... it's little slivers of soft metal(bearings) that go between two chunks of hard metal(the rod and rod cap)... nothing more.

Like I said, I've done and witness MANY "backyard rebuilds" and never seen or experienced any problems. I'm not just an unknowledgeable punk... I know what I'm doing and wouldn't recommend that anyone else do it if it wasn't "doable".
 

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14.1 @ 100mph N/A
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Discussion Starter · #15 ·
moparjim said:
You yourself fell prey to the possible boobery I mentioned by managing to create an oil pan leak in the process...
No "boobery" here. My girlfriend put on the sealant and didn't put it on thick enough... nothing catastrophic. I planned on pulling the pan after a few miles anyways, so I left it alone... we ended up with a small drip for the first day, and I fixed it the second day when I pulled the pan again.

I'll pull the pan often to check everything out and give you/everyone updates. I'm glad to be the guinea pig... someone has to do it.
 

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You break em, we fix em
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Not exagerating - LINT FREE GLOVES. I too have rebuilt many engines, and have spent the last 6 years as a DCX engineer at an engine plant producing 3,000 engines per day. I see our warranty returns - 1 speck of dirt, lint or anything ON THE BEARING OR ROD SURFACE will indeed ruin the bearing and either score it or cause it to spin. 1 speck or anything will even lock up the engine so that the torque to turn testers here can't even turn it. Of course I have seen interesting things in the oil pan - I am talking about damage or contamination of the rods or bearings while handling - its past the filtration system already.

I hope I have not in anyway insinuated that you are an "inexperienced punk", infact I believe I praised your mechanical ability. It is the others that read your thread title "SIMPLE rod bearing replacement" that concern me!

And if your girlfriend put on the sealant, that DEFINITELY sounds like "boobery" to me ;)
 

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WICKEDDREW said:
Do you only have 60k-ish miles? If so, I'd recommend waiting until 100k to do the bearings unless you're just bored to death and want to get your hands dirty. Like I said before, I'd recommend switching the 60k/120k tune-ups to 50k/100k, and doing the rod bearings and oil pump at 100k.
i've got 175K...i'm doing the third 60K :)

~matt
 

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14.1 @ 100mph N/A
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Discussion Starter · #18 ·
I added a good link to the first post of this thread, and everyone should read it.

Here's a quote:

"if you suspect bad bearings, the only way to know for sure is to pull the oil pan, remove some main and rod bearing caps and inspect the bearings. If the bearings are worn, they need to be replaced. But if they show evidence of damage or unusual wear, it’s pointless to replace them until you’ve diagnosed the underlying problem.

At this point in the process, you have to make the call as to whether replacing the bearings is worth it or not. If the bearings are only worn and everything else appears to be okay, a new set makes sense. On the other hand, if the bearings are damaged or smeared, the crankshaft may need to be reground or replaced, and one or more connecting rods may have to be reconditioned, straightened or replaced. It all depends on the damage and what further inspection reveals."
 

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haha, you blamed your gf for the oil pan.... :rolleyes: that's pretty low man. if my gf messes up working our cars, you know whose fault it is for not double checking??? exactly. :)
Matt
 
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