Help! Trying to remove timing chain guide rail on M30

[bmwpower]

Got everything off, but the headgasket is in the way. I can't remove the guide rail. Any help?!?

I can't imagine I need to cut the headgasket to get the guide rail out, right??

http://www.realoem.com/bmw/showparts.do?model=HD23&mospid=47408&btnr=11_1187&hg=11&fg=25

[bmwpower]

see attached. I thought about bending up the headgasket (like I did to get the tensioner rail off of the left side), but the guide rail is too tall... :(

WTF? help!

[atl530i]

That's weird. There are no visible bolts holding that in??

[bmwpower]

How about unscrewing this post (marked with red arrow)? Not sure how long the threads are or if I should even attempt.

[bmwpower]

That's weird. There are no visible bolts holding that in??

There are actually "posts" that it slides onto. Circlips on the end of the posts hold it secure (I already removed the circlips).

[atl530i]

Yeah, if I were in your shoes I'd have a 6 pack under my belt by now figuring that out. :)

[kalevera]

Been like....two years...since I've done one of these, but from what I remember it can be removed without destroying the head gasket. Extremely difficult, though, just to get the chain out of the way. Edit: the more I think about it, the more I remember it being necessary for the head to be off to replace that guide, but it shouldn't really be wearing, anyway, it's the tensioner/rubber padded that does that.


You're in far enough that you might as well change the head gasket, anyway, for good measure ;)

[bmwpower]

Been like....two years...since I've done one of these, but from what I remember it can be removed without destroying the head gasket. Extremely difficult, though, just to get the chain out of the way. Edit: the more I think about it, the more I remember it being necessary for the head to be off to replace that guide, but it shouldn't really be wearing, anyway, it's the tensioner/rubber padded that does that.


You're in far enough that you might as well change the head gasket, anyway, for good measure ;)

Nooo! I've already done to headgasket a little while ago. Bentley makes it sound like you just replace it.

[Elvis T]

Nooo! I've already done to headgasket a little while ago. Bentley makes it sound like you just replace it.

The chilton isn't much better with some of the things they describe. Like replacing the clutch master cylinder.....:mad

I had an 89 ford Ranger and the manual I had for that was amazing! It would even tell me that I needed to turn the bolt ccw to loosen it. :buttrock

[Mr Project]

I hate to admit this, but I spent hours trying to figure that out, and couldn't. I cut the headgasket. A very clean, angled cut, and then used some very nice permatex gasket maker on re-assembly. Not just the RTV stuff. At that point, the HG only had 15k on it, so I really didn't want to replace it again.

Remember, that portion of the HG doesn't hold combustion pressure or anything, it's just an oil seal.

[HE53]

I hate to admit this, but I spent hours trying to figure that out, and couldn't. I cut the headgasket. A very clean, angled cut, and then used some very nice permatex gasket maker on re-assembly. Not just the RTV stuff. At that point, the HG only had 15k on it, so I really didn't want to replace it again.

Remember, that portion of the HG doesn't hold combustion pressure or anything, it's just an oil seal.

I think he's right.. The guide has to come straight off. Why didn't you replace that when you had the head off?

[bmwpower]

I think he's right.. The guide has to come straight off. Why didn't you replace that when you had the head off?

I'm guessing you've never done the procedure :)... it's a PITA and requires getting that crank nut off/on. Plus...according to Bentley, I could just replace the guide without doing anything with the headgasket.



I hate to admit this, but I spent hours trying to figure that out, and couldn't. I cut the headgasket. A very clean, angled cut, and then used some very nice permatex gasket maker on re-assembly. Not just the RTV stuff. At that point, the HG only had 15k on it, so I really didn't want to replace it again.

Remember, that portion of the HG doesn't hold combustion pressure or anything, it's just an oil seal.

That's exactly what I did. I tried to unscrew the top post - didn't work. The threads are too long. I cut the gasket up on the "dry" side and sealed it with Permatex "The Right Stuff" - my sealant of choice for something like this. That friggin part of thehead gasket always leaked anyway, so I threw thin layer of sealant top/bottom for good measure.

[HE53]

I'm guessing you've never done the procedure :)... it's a PITA and requires getting that crank nut off/on. Plus...according to Bentley, I could just replace the guide without doing anything with the headgasket.



Actually I've done the same thing with a couple different M50's.. It is more of a PITA on an M50 style motor too. Its just easier to do it all at once. One an M50 you can't pull the upper timing cover off because its part of the head. To pull the lower off you have to drop the pan or pull the head and take that stupid crank bolt out.

Seems that Mr. Project has the only decent idea as to replacing it without pulling the head. I'd cut it once in the front and just pull it back enough to pull that guide off. :dunno def sucks..

[attack eagle]

I cut the gasket up on the "dry" side and sealed it with Permatex "The Right Stuff" - my sealant of choice for something like this.
Absolutely the best sealant/gasket maker ever. I will never use anything else again.

[black535]

I just angle cut mine also, then bend up gasket. reassemble with a gasket sealant of choice. it's worked fine for over 20,000 k.

[Racerhoze]

I don't understand why that guide rail is plastic in the first place. It gets brittle being in hot oil all the time. When I did my hg, I thought I would save myself time by keeping tension on the timing chain, but I ended up just breaking the guide rail. What a PITA.

[strayts]

any progress made?

[bmwpower]

any progress made?

Yea, I ended up just cutting the headgasket on the high side (driver's side of housing) with a pair of wire cutters (since it's metal core). Don't cut it on a corner. Don't cut it on the passenger side of the housing - that side is always oily, more chance of a leak. This allowed me to slip everything out and slip the new stuff in. Just be careful with bending the headgasket. It has a tendency to crack and fall apart. Then I just sealed the cut up with The Right Stuff. I also placed a light coat of The Right Stuff on both sides of the headgasket in that area. There's just not enough pressure to keep it from leaking normally, IMHO. No problems so far.

Man, a new timing chain sure does seem to make a difference in throttle response. Throttle is lighter and smoother. Hopefully, it should become even better once I adjust the valves (this weekend).

Thanks for the help guys!