M54 head gasket project

[ahlem]

I am tearing down my 2001 M54 170K miles motor to change the head gasket.
It's pretty much as advertised so far. There are Youtube videos by a couple people including "That 50's kid" that are very helpful.
As anticipated, the plastic parts are pretty brittle after all these years and 170K miles of heat cycles. I am changing the timing chain guide parts and had a couple questions...

Do you have to drop the oil pan enough to get the timing chain cover off and in the process need to replace the oil pan gasket or can this be done without as much involvement?
I'm replacing the crank bolt and washer and crank seal.

With the 170K miles, it would seem reasonable to change at least the primary timing chain while I'm in there. Is that advisable?

Anything else I should be doing at this time?

[oldskewel]

I did my 2001 M54B30 a couple of years ago. Sounds similar to yours, except I was also getting combustion leaking into the cooling system. 186k miles at the time, 194k now, running great.

No need to drop the oil pan just to change the chain guides, but you will need to drop it if you decide to replace the chain. I did not replace my chain, and don't see any reason to do so.

BTW, from what I've read, etc., the problems you're having in the middle cylinders there is fairly common and I would not expect there to be significant problems through the rest of the engine just because of that compression loss in 4+5. Could be a HG, but also maybe a warped or cracked head. So have the head inspected carefully. Easy to miss a problem there - even the 50sKid (you'll see - all covered in the videos) got his head all cleaned up, disassembled and off to machining, where they then found the crack.

I did a VANOS rebuild at the time. No problems before or since. I did not change the VANOS solenoids - not so hard to get to later if ever needed.

I replaced the crank seal but reused the bolt, washer, and pulley. I have a thread on here somewhere about the crank bolt removal.

Main advice is to not screw anything up. Really. You don't do a great job at this. You either do it without mistakes or you make a mistake and recover the best you can. Also planning to allow for patience will help you do it with less stress and more fun. That's what I did. So, a good work place, alternative transportation, etc.

Good luck.

[Effduration]

Done this a couple of times. I time-sert the block every time I take a
m54 head off as it is really easy for DiY’er with a torque wrench to strip
Threads when you put it all together.

Do the coolant pipes and oil filter housing, CCV and Intake gaskets While intake is off

On the x5 I install head with exhaust manifold bolted on, and I remove the washer tank for better access.. I use an engine hoist to lower it in..a 2nd set of hands helps..

Elring gasket

[andrewwynn]

That age the oil pan gasket is very close to end of life.

[Effduration]

Doing the Vanos seals makes sense....

Do you have the Vanos timing tools to re-time the vanos/camshafts?

[oldskewel]

Originally Posted by Effduration

Done this a couple of times. I time-sert the block every time I take a
m54 head off as it is really easy for DiY’er with a torque wrench to strip
Threads when you put it all together.

Do the coolant pipes and oil filter housing, CCV and Intake gaskets While intake is off

On the x5 I install head with exhaust manifold bolted on, and I remove the washer tank for better access.. I use an engine hoist to lower it in..a 2nd set of hands helps..

Elring gasket

I agree on all this except I put the head and exhaust manifolds in separately.

Good point on the TimeSerts. That's exactly what I did too. From what I read / heard, the same heat that causes the head failure (e.g., heat related warping or HG failure) will cause the block to weaken, making it likely to have threads pull out upon reinstallation of the head.

Coolant pipes too. Don't make the mistake I did by using non-OE o-rings. It's buried kind of deep, and not something you want to get to again.

Timing tools are pretty much essential. I bought them on eBay for about $100 and sold them for almost that on Craigslist after getting it all done.

In my case, the HG was fine and the problem was a warped head. Depending on how much machining the head needs (how much comes off to make it a flat surface again), you may need a regular (0.7 mm) or thick (1.0 mm) HG, so you might need to wait for the machine work before buying the HG. I bought a full HG set but without the HG, and then bought the 0.7 mm HG later, separately. I believe Elring, Reinz, and BMW are the good choices for the set and for the head bolts.

For me, CCV had been done by the dealer prior to purchase, and I had done the OFHG shortly after buying, so those did not need anything on my car. But yes, they are all right there with easy access and on most cars, it would be a good opportunity to do it.

Similarly, engine mounts are right there too. But I did not touch mine. No problems.

Much of the cooling system comes out and would be easy to replace with new.

When I did mine, I took everything slowly so I could choose to fix things opportunistically if it made sense. So for example, I "rebuilt" the starter too. Made everthing more of a fun project and less of a chore.

[ahlem]

Update..
The head gasket is split between 4 and 5 and 2 and 3. The 4-5 split is larger.
I haven't checked the head with a straight edge yet. I'm putting together an order for parts that need to be replaced due to inspection while taking things apart.
I have the cam timing tools and will figure out the Timeserts shortly. What is the advantage of Timeserts vs Helicoils? I've heard that Timeserts are preferable from some e30M3 racer types but would welcome additional opinion based on facts. Currently doing the cleaning up part before I take the valves out and any machine work gets done.

[Effduration]

I use made-in-Germany Beck/Arnley #016-1048 head bolts and am happy with them.

Time-serts are a better threaded insert than a heli-coil in this application.

- It's a sturdier insert that can withstand several torques/removals
- Time-sert makes a specific tool kit/jig for M54 engines (Kit 1090)*
- far more BMW forum members (e46, e39, E53) have used time-serts than heli-coils in a block application.

* Full disclosure - I own kit 1090 and occasionally rent it out to forum members. However, for same or less money you can buy it new/used and sell it on ebay.

[ahlem]

Has anyone done the Timeserts using alternative drills and taps to those in their kit?
I'm thinking of buying the inserts first and then measure the OD and thread pitch and see if I have the right tooling. I can make pretty much anything in the kit and at their price I may be money ahead.

[oldskewel]

I did the TimeSerts using their $100 kit, but not the $400 BMW kit.

Some notes I took back when I did it:
Head bolts are M10-1.5

inserts cost about $2 each

kit costs about $100+, including: a tap for the insert's outer threads; drill bit; a counterboring tool to make a little groove for the "top ring" (below) to seat in; an insertion tool / forming (vs. cutting) tap to install the insert into the tapped hole; a few inserts and a plastic box. All of the above seem to be very high quality. Machine shop quality vs. hardware store.

Inserts are made of mild steel which appears to be black oxide coated. So they have a slightly rough surface finish.

- The kit contents might be completely standard parts, not requiring the special kit, so maybe you could skimp on cheaper taps and make do without the counterbore and special insertion tool. Details on this below.

- e.g., a M10-1.5 insert will have outer threads of M12-1.5. Same exact pitch (1.5 mm here), since that's what the "time" is in timesert - that the threads are synchronized. An M12-1.5 tap is a standard size that can easily be bought as a standalone piece. So for example if you just need to put one insert in an easy application, you could just buy the $2 insert, a <$10 tap at the hardware store (if you did not already have it), and would be good to go.

- There are two main features of the insert - top ring and bottom threads

- Top ring. purpose is to stop the insert from threading in any further. There is a wider ring around the outer edge at the top of the insert. The kit comes with a special counterboring tool to make it so the fully inserted insert will be flush with the surface of the material. A less precise substitute for the special tool would be a slightly bigger drill bit to countersink a little. That's what I ended up doing on the M54, since the threaded holes were countersunk already by about 6 mm - so the counterbore tool in the kit was no use, and I used an oversized drill bit to go in about 8 mm.

- Bottom threads. This is the more critical aspect.

- The bottom 2 or 3 threads are normal on the outside (e.g., M12-1.5), but on the inside (e.g., M10-1.5) surface of the insert, they are not triangular, but rather rounded. The concept is that when the insertion tool/forming tap bottoms out the insert (when the top ring bottoms out against the counterbored surface), the insertion tool will then drive and forge / form / tap (as if tapping threads, but by forming rather than cutting) through these bottom threads, except that rather than cutting away the extra material, they cold-form it into sharp triangular threads, and also deform the outer surface of the insert, pressing it into the block, making the insert permanently pressed into the block, so it will not unscrew.

- So the tap forming tool looks like an extremely sharp and perfect screw, with a roughly squared end to it. I think the squared aspect is to focus the pressure on the 4 corners rather than having to cold form and press the entire circumference at once.

- That's all the theory, and I think it's all good. But actual practice has some issues.

- First one, is that the instructions are not clear on how much to insert the insertion tool into the insert before inserting the insert into the block. Presented as if it does not matter. My findings are that it does matter, and best is to insert the insertion tool into the insert right up until the bottom threads are engaged, then insert the insert into the hole, then when it bottoms out at the top ring, the insertion tool will cold form the bottom threads, seating the insert. I put thread locker on the outside of the insert / inside of the hole as well to keep the insert locked in place. Main problem I found with that approach (and even worse when not pre-installing the insertion tool/tap into the insert) was that the insert would stop inserting before it bottomed out, and then the cold-forming would occur, locking it in place too early. And too late to fix.

- Solution, which worked great, was to:

- use an existing regular bolt as the first insertion tool. It should be smooth fitting within the insert since it will be removed, leaving the insert behind, before the insert is locked in place. Put some oil on it for easy removal, thread locker in the block hole and outside of the insert. insert bolt into insert, right up to the bottom threads.

- then insert the bolt+insert all the way until the top ring seats. Ideally, this will happen without the bolt starting to go past the bottom threads.

- remove the bolt. Hopefully the insert stays where it is, with more friction on the outside of the insert, vs. the oiled inner surface.

- then insert the oiled insertion tool/tap, all the way through past the bottom threads, cold forming them and embedding the outside of those threads into the block threads.

- unscrew the insertion tool/tap, and done.

- the youtube 50skid did not buy the kit. He thought the insertion tool / tap could be completely substituted for with a regular bolt. He got it done, but I think if he actually had an insertion tool/tap, he'd have understood the utility of it.

- I can guess that the kit wants to make itself look specialized and needed, so they don't mention using a bolt as stage 1. Also, like everything else in making things, people are obsessed with speed and efficiency, and timesert probably wanted to reduce the number of steps. But it's pretty clear to me that other than adding a step, there is no downside to using a smooth bolt first, and then the cutting insertion tool/tap to finish the insertion.