[pearlpower]

Took around 17 hours total. It was not exhibiting any strange issues, as others have posted around on the internet. Mine was more preventive as I intend to drive the car a few more months (daily beater), and I had some time off over the holidays to get it out of the way. Overall the car has been extremely reliably to me in the 100k miles I have had it. Only mod is JB4.2. As an FYI, Liqui Moly 5w-30 every 5-7k miles, average around 5500 miles. ASS coded off.

While in there I inspected the rod bearings and they were shot. The last motor I rebuilt was my E55 AMG and those rod bearings were in great shape, this tiny little motor takes a beating, and I do beat on it.

I used the cam kit, flywheel lock, oil pump/balance shaft bolt kit, and engine brace. Apart from that I have all of the tools required.

Over 350 miles and it runs great, a little quieter (resealed the cat, perhaps), no leaks, and pulls nice and smooth. The old guide did have two broken tabs, unsure how long it would have lasted. I broke off a a few pieces on the bottom during removal, plastic was a bit brittle in spots.

Piece of mind...............















While not necessary, I always remove the sub-frame when I can to give me plenty of room. When I'm playing gymnastics under a car, I tend to make more mistakes.




All done.

[Slick_FThirty]

Originally Posted by pearlpower

Took around 17 hours total. It was not exhibiting any strange issues, as others have posted around on the internet. Mine was more preventive as I intend to drive the car a few more months (daily beater), I had the some time off over the holidays to get it out of the way, and overall the car has been extremely reliably to me in the 100k miles I have had it. Only mod is JB4.2.

While in there I inspected the rod bearings and they were shot. The last motor I rebuilt was my E55 AMG and those rod bearings were in great shape, this tiny little motor takes a beating, and I do beat on it.

I used the cam kit, flywheel lock, oil pump/balance shaft bolt kit, and engine brace. Apart from that I have all of the tools required.

Over 350 miles and it rungs great, a little quieter (resealed the cat, perhaps), no leaks, and pulls nice and smooth. The old guide did have two broken tabs, unsure how long it would have lasted. I broke off a a few pieces on the bottom during removal, plastic was a bit brittle in spots.

Piece of mind...............















While not necessary, I always remove the sub-frame when I can to give me plenty of room. When I'm playing gymnastics under a car, I tend to make more mistakes.




All done.

Amazing work! Makes me wonder what I should be doing with my chain (original @ 72k km). Had it inspected at my dealer hoping for replacement under warranty, but they said it's fine.
Never really heard of rod bearing issues though on the N20.

[pearlpower]

Originally Posted by TechiGamer

Amazing work! Makes me wonder what I should be doing with my chain (original @ 72k km). Had it inspected at my dealer hoping for replacement under warranty, but they said it's fine.
Never really heard of rod bearing issues though on the N20.

Rod bearings are not as prevalent as the timing issues, but since I was in there, only made sense. Anytime I pull the pan one of my cars I will swap out the rod bearings.

https://bmwtechnician.com/2016/03/31/n20-rob-bearing/

[Slick_FThirty]

Originally Posted by pearlpower

Rod bearings are not as prevalent as the timing issues, but since I was in there, only made sense. Anytime I pull the pan one of my cars I will swap out the rod bearings.

https://bmwtechnician.com/2016/03/31/n20-rob-bearing/

Interesting, thanks for the info. Something else I should keep in mind. Good work.
How difficult did you find it to replace the TC? Obviously it varies by skill and knowledge, but is it possible for a technically inclined newbie?

[pierreye]

Great job which I couldn't have perform. Anyway, are the intake valves clean on N20? Been thinking if oil catch can is really necessary on N20.

[Naiters]

Originally Posted by pierreye

Great job which I couldn't have perform. Anyway, are the intake valves clean on N20? Been thinking if oil catch can is really necessary on N20.

Yeah, how about the intake valves condition after 100k miles?

[Billfitz]

Originally Posted by pierreye

Been thinking if oil catch can is really necessary on N20.

I haven't looked at my valves, but my catch can is picking up oil, so it's doing its job.

[pierreye]

Been reading that oil catch can doesn't pick up any oil residue in hot climate. I try to install one in my engine bay (didn't connect the pipe, just to check if it mount properly) and after 20 mins drive, the aluminium can is very hot to touch. I suspect could be due to hot climate here which is consistently around 32-34 degrees celcius, the oil vapour might not have time to condense in the can before going back into the air intake pipe.

[pearlpower]

Originally Posted by TechiGamer

Interesting, thanks for the info. Something else I should keep in mind. Good work.
How difficult did you find it to replace the TC? Obviously it varies by skill and knowledge, but is it possible for a technically inclined newbie?

Should not be an issue provided your not rushed. You would need the specialty tools, available on Amazon:

https://amzn.to/2QOt2o2
https://amzn.to/36SrZJl
https://amzn.to/2FOh6MI

Would need a small bit kit for the vacuum pump as space is limited behind the valve cover.

https://amzn.to/3a3epVz

A torx set, similar to this, with internal and external.

https://amzn.to/30idSuc

Torque wrench, torque angle tool, variety of extensions & sockets in 1/4, 3/8, 1/2. A breaker bar and long pipe (crankshaft bolt).

Engine brace to suspend the motor (Harbor Freight w/ 20% coupon), jacks, stands, etc....

Keep in mind TIS is very limited in scope, missing many steps.

[Dylantm]

Thanks for sharing all of the information, I was following your thread on the FB group as well.

One thing I'd like to say though...coming from someone who has worked in the automotive industry for 14 years and turning my own wrenches since I was 16...

I feel that it is irresponsible to tell people who are self proclaimed "newbies" it's not that bad of a job, or that is is a 6 of 10 difficulty (as you did on FB). You obviously have alot of skill, patience, and this isn't your first time doing a rebuild.

Your 6 out of 10 is someone else's halfway torn apart engine getting towed to the shop because they cant complete the job.

[pearlpower]

Originally Posted by Dylantm

Thanks for sharing all of the information, I was following your thread on the FB group as well.

One thing I'd like to say though...coming from someone who has worked in the automotive industry for 14 years and turning my own wrenches since I was 16...

I feel that it is irresponsible to tell people who are self proclaimed "newbies" it's not that bad of a job, or that is is a 6 of 10 difficulty (as you did on FB). You obviously have alot of skill, patience, and this isn't your first time doing a rebuild.

Your 6 out of 10 is someone else's halfway torn apart engine getting towed to the shop because they cant complete the job.

You should reread it. What I stated was:

It would take a bit of experience. From a 1 to 10, around a 6. Just need tools, and time, plenty of time. Also the specialty tools such as flywheel lock, oil pump lock, balance shaft lock, camshaft lock, etc.

I also posted:
TIS is good for a general guide, and torque values. It is limited to very limited in detail. Some instructions are only 20% of what is really needed to perform the particular job. This is where experience comes into play.

Also:
If someone does not have the correct tools that will add to the time as folks tend to get creative when they do not have the right tool, and that invariable adds time and frustration.

What would I consider a 10 out of 10? A Porsche 928 S4 engine rebuild, transmission rebuild, etc. Everyone has different skill sets and experience. Just the same as someone putting on brakes can cause an accident if not properly done. It is up to every person to ascertain their own skillset and make a decision. All of us have been in a position where we tackled a project we were not familiar with. A technically inclined “newbie” description tells me little about their skills, tools, ability to follow instructions, watch YouTube videos, post help needed threads, etc.

I get the point your trying to make, just disagree with your assertion. We can agree to disagree, as they say.

[User3Hundred]

Which rod bearings did you buy? On fcp euro there’s 4 options for oem rod bearings. Red, yellow, violet, and blue. Not sure which ones and how many of each to get.

[nodemgr]

Originally Posted by Naiters

Yeah, how about the intake valves condition after 100k miles?

Here's one of mine at 115k, they all looked about the same...wasn't worth my time to clean them.

[Taylorsi]

Hi All - First post, I dont mean to hijack this thread but I havent found others discussing rod bearing replacement so figured I might have luck here.

I am getting ready to replace the timing chain on my 145K mile 2012 328i with original guides, tensioner, etc and seems logical to replace the rod bearings while I am in there. Car is 100% stock and runs/drives very well (no codes in ISTA etc) and it was dealer maintained for its entire life until I purchased it at 139K (2nd owner). All of this is preventative maintenance as I intend to keep the car for a long time. Looking for guidance since ISTA isnt much help as the rod bearing replacement process seems to assume the head is off.

Questions:
- Once the everything is set to TDC (via crank pin and oil pump/balance shaft key), can I remove the oil pump/balance shaft unit (and crank pin) to safely turn the engine to replace the bearings, or will the oil pump chain drive bind up? (Sounds like this is the case on the N55, but the N55 oil pump drive also appears less robust)
- Are the rod bearings replaced before or after the rest of the timing components? (IE on disassembly or assembly)

It seems I can set the engine and oil pump/balance shaft unit to TDC, remove the oil pump/balance shaft unit, remove the crank key to turn the engine and replace bearings, set engine back to TDC, then install oil pump/balance shaft unit and continue with assembly (or disassembly if performing rod bearings first is optimal). The main concern is really around how to safely turn the engine given the oil pump drive will be attached to the crank still.

I have many tools (including all of the specialty N20 tools) and reasonable mechanical experience so I feel comfortable with the timing chain replacement using the FCPeuro kit, their video guide, and ISTA, mainly just unsure of the best order of operations for the rod bearing replacement at the same time.

Hopefully pearlpower can advise... but advice from anyone else with experience will also be greatly appreciated!