m30 Head Disassembling ?

[tsweers89]

So my 535 blew a head gasket. Got the head off last weekend and am in the process of taking it to the machine shop to get it tested for cracks, straightness,etc. Well the place im bringing it to syays i have to disasemble the head first before i take it there. I have been looking through all the cabinets and such for a repair manual on how to do this but cant find one, and no one here at the dealer remebers how to. hah Have to take out the cam, valve spring, valves, etc. So any help? i need directions for this.

Thanks

[Binjammin]

If you don't know how, you may be better off paying the machine shop to do it. You'll need a valve spring compressor tool, spend the money on a c-clamp type. The overhead screw-type compressor won't work on one valve as there's interference from the head and a coolant passage.

Seriously, a machine shop can break down a head, they just hate to because they always lose small parts. ALWAYS. If you bring them a complete head they have fewer excuses.

[tsweers89]

If you don't know how, you may be better off paying the machine shop to do it. You'll need a valve spring compressor tool, spend the money on a c-clamp type. The overhead screw-type compressor won't work on one valve as there's interference from the head and a coolant passage.

Seriously, a machine shop can break down a head, they just hate to because they always lose small parts. ALWAYS. If you bring them a complete head they have fewer excuses.

i have all the bmw special tools to do it, just dont know what is what as we usually just go by the part # on the tool. But all the old repair instructions on bmwcenternet are not working properly and we dont have the books anymore. Also no one in the shop has done one except for an old guy and he doesnt remember how. I need to know how to get the rocker shafts out and then ill be good from there.

[Binjammin]

I don't understand how you can be a tech with all the tools and not understand how to do the job, but basically remove all the circular wire clips from the rocker shaft. They're covered by round washer-things (idk wtf to call them) next to each washer. Slide those things off and you'll see the clips. Each rocker shaft is actually split in two, remove the head, install the valve compressor tool, thread a bolt into each rocker, and pull the rocker shaft halves out.

For the front one, you'll need to either remove the timing gear flange first, or align the gaps in it for the rocker shaft to come out.

If you have any idea what you're doing disassembly should be pretty easy.

[tsweers89]

I don't understand how you can be a tech with all the tools and not understand how to do the job, but basically remove all the circular wire clips from the rocker shaft. They're covered by round washer-things (idk wtf to call them) next to each washer. Slide those things off and you'll see the clips. Each rocker shaft is actually split in two, remove the head, install the valve compressor tool, thread a bolt into each rocker, and pull the rocker shaft halves out.

For the front one, you'll need to either remove the timing gear flange first, or align the gaps in it for the rocker shaft to come out.

If you have any idea what you're doing disassembly should be pretty easy.

we dont deal with these motors on an everday basis and the spcial tools for the old engine are just in a box everywere. Also the repair instructions are no were to be found. give me a m54 or n54 and i can have it apart in 15min. You act like techs are suppose to know everything for everything off the top of their head, a lot of stuff we use directions for. As would be the case with this old m30

[JesterMX6]

all heads have the same basic design. work on one head you've worked on them all.

[tsweers89]

thanks for the help though. i just found all the special tools i need.(were in a drawer behind a bunch of engine wiring harnesses. The box has about a 1" of dust buid up on it so i assumne these havent been used in many many years.


all heads have the same basic design. work on one head you've worked on them all.

True to some extent but as stated i couldnt find the special tools so i was woundering what other people have used as i was planning on buying them up till now when i found everyhting i needed.

[JesterMX6]

well as bin stated, the only "special" tool needed is usually the valve spring compressor because some of them don't work with the head and angle of the valves. other than that, i have no special tools as i've never been in a position where i've needed one and because they're a huge rip off unless buying used and a very unnecessary shop expense.

once you start digging into it you'll see how basic it is. its a 1980's design. not much there.

[tsweers89]

i just got it all apart. bmw has the head holder, this girdle thing that goes over the head and slides into the rockers and the valve spring compressor. very simple once i found the right tools.

[Isaacus]

Kinda nice just randomly having access to thousands of dollars worth of tools that only were designed for the specific job you're doing.

[ILoveMPower]

M30 has got to be one of the most basic cylinder heads out there... just look where stuff goes and take it off

[motohunter4]

I thought the M30 was a 60's design?

[bam2002]

Try a different machine shop. I have taken the one here, M20, M50 and even a head from a Citroen, They pulled them apart with no problems. And re assembled. Even matched up valve parts from a Porsche for the Citroen.

[Binjammin]

we dont deal with these motors on an everday basis and the spcial tools for the old engine are just in a box everywere. Also the repair instructions are no were to be found. give me a m54 or n54 and i can have it apart in 15min. You act like techs are suppose to know everything for everything off the top of their head, a lot of stuff we use directions for. As would be the case with this old m30


Sorry man, I don't know what to tell you. I've been an indy tech for a LONG time now, and it's a job that typically doesn't come with manuals and instructions. Most jobs require just knowing how stuff works. I never had a manual to learn how to break down an m20 or m30 head, I just did it. Same thing with an m52,54 etc. They're even easier :p

It's like saying "I can't work on a ford engine, I'm a chevy guy." Well, yeah, maybe that's true, but unless you've got a turbine or a rotary they're all pretty much the same, and even turbines and rotaries are pretty simple. You know how valves work, you know how cams are driven, you know how an ignition event happens, diagnosing these things comes from knowing what happens when one of them goes wrong. Of course I'm generalizing a bit, but generalizing is how it all happens. You've seen one engine, you've seen 'em all really is the truth for a guy like me.

[tsweers89]

Sorry man, I don't know what to tell you. I've been an indy tech for a LONG time now, and it's a job that typically doesn't come with manuals and instructions. Most jobs require just knowing how stuff works. I never had a manual to learn how to break down an m20 or m30 head, I just did it. Same thing with an m52,54 etc. They're even easier :p

It's like saying "I can't work on a ford engine, I'm a chevy guy." Well, yeah, maybe that's true, but unless you've got a turbine or a rotary they're all pretty much the same, and even turbines and rotaries are pretty simple. You know how valves work, you know how cams are driven, you know how an ignition event happens, diagnosing these things comes from knowing what happens when one of them goes wrong. Of course I'm generalizing a bit, but generalizing is how it all happens. You've seen one engine, you've seen 'em all really is the truth for a guy like me.

only question i really had was how to get the rocker shafts out as we usually used a slide hammer but i could find it, just seeing what everone else did. throught maybe the rocker shaft threads were special threads, but i guess not. Also im pretty new to the buisness. Only 3 yrs in it so give me a break. hah. Thanks for the help, off to the machine shop it goes to get checked.