Sub'd to remind me to quote you tonight. I imagine its about 8-10hr. Back when I wrenched full time, it was a 2hr disassemble and 4hr reinstall. Takes me a bit longer now, out of practice + bad back...

Also - You have a 98? That's an iron block, no need to repair threads... If your mechanic doesn't know that, run. And I'd add in 6-8hr for the repair of threads, based off my experiences last month. And a $650 tool to do it. (My car is a 99 w/ M52TU, alum)

Thanks for the reply. In my research I did discover the fact that the pre-9/98 builds have an iron block, but I didn't know that translates into no possible engine block thread damage with a blown cylinder? That would be good news indeed as I have come to understand, the possibility of stripped threads is a primary risk of going with the cylinder repair route )vs engine swap), next to the risk of a badly cracked head of course.

Would you, or others, verify if I got this right?

Thanks.

sorry i have question for you, did you overheat your vehicle?

yeah. Have had overheating problems every 6 months on this car for 5 years (1998 528I A with m52 engine)... did all the cooling system replacements, but kept coming back.

About 60 days ago, got a misfire code cylinder 3 (0303 i think). Was hoping it was a bad ignition coil, but the overheating started much more frequently.... Never got into red more than a minute or so. (The one time it happened while gf was driving she thinks it wasn't more than a couple minutes that time )and after bleeding it would be fine for a few drives than start overheating again; then the white smoke.... then wouldn't start (water in the cylinder(s)). Mechanic pulled the ignition coils and plugs and started car to shoot out the water. Then started fine.

Having the cylinder head pulled over the next few days, and sending off to machine shop. Hoping threads aren't stripped and head not cracked (too bad). If I'm lucky it will be fixed for $1,250, or, if a used or refurbed head is needed add on $450 to $700 more, assuming no thread stripping in block. The pre 9/98 block is iron so I have my fingers crossed.

Fortunately, the repair will cost alot less than I originally feared - my mechanic only charges $55 an hour and he has alot of experience with these m50/ m52 / m50tu engines.

Should know more by next Wednesday or Thursday.

Any observations / advice / comments are good.

You should be fine with that mechanic.
The M52 block is iron and should be fine.

- Make sure your mechanic uses only BMW dealer head gasket.

- Then review the entire cooling system records and refresh any questionable part(s).

ok thanks i was curious. Insane how you replaced the cooling components and yet the vehicle would still overheat every 6 months for such a long period of time, this baffles and saddens me . Hopefully it will be fully operational after the repairs are completed.

bkgreene - no problem, happy to share.

cn90. Thx for reply, yes mechanic plans on using BMW head gasket only. Also, thanks for your many posts re cooling system issues. Have visited them many times.

In this diagram

http://www.realoem.com/bmw/showparts.do?model=DD63&mospid=47585&btnr=11_1555&hg=11&fg=35

there are 7 hoses re cooling system. Many cooling threads don't mention hose # 12 and #14. I think we finally got around to those after third or fourth overheating episode. And actually, things were good for quite a while after those were replaced (maybe a year and 1/2?) until the most recent incident.

Hose #9 I don't think has ever been replaced. My mechanic said you have to remove the engine to get to it. Well, now he has his chance. Maybe that was a source of some of my problems as well. Guess we will see late next week.

Thanks again Sigma for the input.... glad to hear about the iron and less risk of thread threading! Made my day as well as potential cost of $1,2000 to $1750 vs. fears of $3,000+ !

I'll post up on developments.

David

PS A little more history: Of course the blown head incident happens after I replace damaged bumpers (replicas) , did other body fixes / painting, and had a $2k stereo system installed (bunch of sound deadening as well). Ready to enjoy the tunes, then the cooling monster does its scorched earth move. Oh, well, must be something in the moon and stars.

And I won't even bother you with what happened to e28 after exterior restoration and stereo system...... now anyway lol

Oh, I forgot to ask... Any recommendations for items to address while engine is apart?

Did Besian (sp) vanos fix, CCV, oil filter housing, and a bunch of the other standard required fixes over time.

How about sending valves (edit meant fuel injectors) for testing, cleaning to a shop? Or is that more for the racer set?

Hopefully, I won't have to get inside this puppy again in the next 10 years. Only 126k miles. I only drive about 4k a year in this car. Seems I spend about that too!

If you've already done Vanos rebuilding, the only thing to do is S52 cams and tuning I'd suggest surfacing the head and pressing in new valve guides and cutting valve seats. That is not required, its based on miles really. My 171k M52tu had very tight guides and the seats lapped very nicely, so I called it good. Same with my 156k M50TU, it felt great. I did put new guide in when I fully rebuild the head for my built motor, but that was a little more all-out (expense++). Tilt spec is 0.2-0.5mm IIRC.

11 12 1 735 180 - REPLACE THIS! Its the oil non return valve. #2 in this diagram. I also always do #7, 8, 9, because it would be seriously annoying if they snapped on retorque. I have never had an issue reusing them on customers cars, but one of my e-friends had issues. I think he didn't use a torque wrench, but I'm down to spend $8 or so on new bolts.

How much coolant does it consume? I ask because if there is water/coolant w the bearings, they won't be happy. Do you drain coolant out when you do an oil change? If no, you're fine.

Thx Sigma. Pardon my ignorance, but which bearings were you referring to? I know not wheel bearings

Also, In above post, I meant to ask if I should send fuel injectors out for testing / treatment...

Napa Pro Link labor guide says 11.9hr. I'm having trouble accessing my server w/ alldata on it ATM, I'll clear that up tonight... That does sound about right, shop times are like that. About 1.5x what it really takes.

Main and rod bearings. If there is much/any coolant down there, they won't live long. This is not normally a problem, unless you're pushing lots of coolant into the oil and then continue to drive it. Have your mechanic drain the oil before starting the job, and inspect for coolant. This is usually NOT an issue - But can be. My e39 was driven for far too long with a couple quarts of water/coolant in the oil, and needs main/rod bearings. Lucky me! Thankfully this means about $400 and a fair bit of work. But I needed to do a steering rack, control arms, and oil pan gasket anyway, so this works out...

I'd skip fuel injector cleaning honestly, our fuel filters do a great job and your car doesn't have that many miles.

Hoses #13 (not #12, which is a clamp) and #14 are easy to replace.

Hose #9 is also easy, it is in the rear of the engine near the firewall. No need to remove engine to do that. Get a mirror and place it back there and you will see it.

Solo1 said:

...http://www.realoem.com/bmw/showparts.do?model=DD63&mospid=47585&btnr=11_1555&hg=11&fg=35

Many cooling threads don't mention hoses #12 and #14. I think we finally got around to those after third or fourth overheating episode. And actually, things were good for quite a while after those were replaced (maybe a year and 1/2?) until the most recent incident.

Hose #9 I don't think has ever been replaced. My mechanic said you have to remove the engine to get to it....

Click to expand...

Thanks much for the education. I guess the main and rod bearings are another level I haven't worked my way down to yet in the engine. This is my first trip to the cylinder head I think the water / coolant in the cylinder is just based on the last few weeks, with maybe 50 miles max driven, most of which weren't when overheated.


Yes, I thought the guides were about 50% high.

Thanks. Yes I meant 13 I'll pass that on to my mechanic about hose #9. He hates it when I quote the forum pros

cn90 said:

Hoses #13 (not #12, which is a clamp) and #14 are easy to replace.

Hose #9 is also easy, it is in the rear of the engine near the firewall. No need to remove engine to do that. Get a mirror and place it back there and you will see it.

Click to expand...

But he will be glad that he learns something new.
Tell him: "Life is a learning process, and don't stop learning until one dies".....LOL.

Solo1 said:

Thanks. Yes I meant 13 I'll pass that on to my mechanic about hose #9. He hates it when I quote the forum pros

Click to expand...

I myself remember being thoroughly confused when I 'overhauled' my cooling system because I bought only the parts most people replace.

I didn't have, when I needed it, the complete list of hoses ... and to this day, I regret not having found and replaced them all.

Anyway, I 'think' we did try to ascertain ALL the cooling system hoses. It 'should' be in one of these threads:
- What parts to replace in an E39 cooling system overhaul (1) (2)

And, maybe here:
- Cooling system heater pipe heater core inlet return pipe leak (1) (2) (3)

Solo1 said:

Thanks. Yes I meant 13 I'll pass that on to my mechanic about hose #9. He hates it when I quote the forum pros

Click to expand...

I "think " I looked, it was a wild constraint, I still didn't find of which you would speak. It "should" be there, but it's not, and equally naked I am with a blown cylinder head! And anyway that was 2010!

It's 2014 almost 2015 and that needle has been straight up ever since that small crack was fixed. Thanks to all of you who advise us so well.