Valve Work?

[1990e30coupe]

I know a lot about my 1987 325e since I replaced every seal, gasket, belt, , and other parts concerning normal wear and tear. The only thing I haven't worked on much after owning four E30's is working on the head. I have found I am able to do valve seals while the head is on the block (after asking around), but I am curious to know if I can change out my rocker arm shafts without removing the head? I know this might come across as a clueless question, but I know what it takes to take the head off and having a horrible knock in the head I want to know how much I can replace without taking it off the block. I can do springs, valve guides, valve seals, new hardware, and rocker cages. Beyond these things I was suggested to replace my rocker arm shaft to help tighten things up.
Unless, without seeing and hearing it run someone can tell me what my knocking (that is beginning to get worse) might be coming from. Maybe there is a common issue that arises that I am out of the loop about.
Any Info will be helpful!
Also after searching around BAV AUTO and other sites it says my valve guides are 13mm, and I just want some clarification since some are different!
I am a "search before I post" person and something's I simply cannot find while others have different answers stating different things creating more confusion.

[jeffnhiscars]

A rocker shaft is not something that causes a loud knock when it's worn. Yes, it's possible to change without removing the head butninsuspect your problem is more substantial

[1990e30coupe]

A rocker shaft is not something that causes a loud knock when it's worn. Yes, it's possible to change without removing the head butninsuspect your problem is more substantial

A rocker shaft is not something that causes a loud knock when it's worn. Yes, it's possible to change without removing the head butninsuspect your problem is more substantial

Understand! If a rocker is loose then what is the cause? since I have cages with play but not sure how much play is allowed as there should be a little. My valves were adjusted wrong by previous owner and I adjusted them correctly so maybe something was ruined with tightly adjusted valves causing my knock . It seems when I adjusted correctly the knock got worse; therefore, maybe new outer springs will help.
Thanks for the info man appreciate it

[Som]

I think you'd have an extremely hard time doing the springs/valve seals with the head still on the block. Pretty sure valve guides are impossible to do unless you did something silly like letting the valve fall into the cylinder, then had a special tool to pull the guides out and press the new ones in (let alone the fact that it's recommended to heat the head evenly before trying to press the new guides in). And then had some way to fish the valves back through the valve guides (gonna place that in the near-impossible category -- I'm envisioning a strong and skinny magnet at the end of the valve stem and... yeah, more like impossible).

For the springs, you'd need a valve spring compressor that's not the C-clamp style. You also need a way to keep the valves from falling into the cylinders, too. Compressed air could be an option, I guess. That said, I'm not sure how easy it'll be to pull the seals while the valve is sitting in it. It's kind of this tapered rubber piece that sits mostly in the valve guide -- there's not much to grab onto without removing the valve.

As for removing the rocker shafts, while it's another one of those "can be done, but it's easier to remove the head" items, it's probably more doable than the seals/springs/guides, though. Here's the thing, though -- to get the shafts out while the head is in the car, from what I understand it's really only "easy" if the shafts were straight to begin with. If the shafts are worn/warped/damaged, I believe you'll need room to get a drift in there and I don't think that's really possible with the head in the car (without doing things like working through the firewall).

I'd also agree that a rocker shaft is unlikely a source of knocking problems.

Can you elaborate on the knocking issue? Is it something that just started randomly? Is it actually knocking or just valvetrain ticking?

Som

[TobyB]

I can do springs, valve guides, valve seals

You can get the rockers out without pulling the head.

But unless the above means "I HAVE DONE the valve guides and seals..."

Just pull the head.

It'll be a lot quicker.

Have you changed the eccentrics? If they get worn, they can be noisy when you
adjust the valves, as that worn spot now puts uneven pressure on the stems...

t

[1990e30coupe]

I think you'd have an extremely hard time doing the springs/valve seals with the head still on the block. Pretty sure valve guides are impossible to do unless you did something silly like letting the valve fall into the cylinder, then had a special tool to pull the guides out and press the new ones in (let alone the fact that it's recommended to head the block evenly before trying to press the new guides in). And then had some way to fish the valves back through the valve guides (gonna place that in the near-impossible category -- I'm envisioning a strong and skinny magnet at the end of the valve stem and... yeah, more like impossible).

For the springs, you'd need a valve spring compressor that's not the C-clamp style. You also need a way to keep the valves from falling into the cylinders, too. Compressed air could be an option, I guess. That said, I'm not sure how easy it'll be to pull the seals while the valve is sitting in it. It's kind of this tapered rubber piece that sits mostly in the valve guide -- there's not much to grab onto without removing the valve.

As for removing the rocker shafts, while it's another one of those "can be done, but it's easier to remove the head" items, it's probably more doable than the seals/springs/guides, though. Here's the thing, though -- to get the shafts out while the head is in the car, from what I understand it's really only "easy" if the shafts were straight to begin with. If the shafts are worn/warped/damaged, I believe you'll need room to get a drift in there and I don't think that's really possible with the head in the car (without doing things like working through the firewall).

I'd also agree that a rocker shaft is unlikely a source of knocking problems.

Can you elaborate on the knocking issue? Is it something that just started randomly? Is it actually knocking or just valvetrain ticking?

Som

Fully understand valve guides not sure why I included them since I am not going to do them, and yes it would be impossible in my book (my mistake in which I feel stupid about).
As for valve seals it is possible, but a time taker and tedious! It will take a little time but still less by keeping the head on if one is determined. If I am working on a set of valves with that chambers piston all the way up it is possible. This of course comes with having the right tools in which you have mentioned. Any idea where I could get a valve spring compressor online that will do the job?
As for the Seals I have seen a slide hammer used and was wondering where I could get one that would grab them?
I am considering pulling the head, but the whole picture is I have redone every seal and gasket (including the head gasket, new timing belt/tensioner). This is minus any head work due to running out of funds after buying the car and doing everything I did to the motor. This is my daily driver so the less time down the better without sacrificing fixing the issue while time is not a huge concern in reality money is at this point, but I try to take care of my car. I'm poor but do the best with the money I have (which when I do have money it goes to my ride). So all in all I have some time, but little money to fix this issue and taking the head off will coast me more; therefore, if it is possible to do the valve seals without getting a new belt, tensioner, gasket, and head bolts I am determined to do it.
As for the knocking, when I got the car there was a tick in which I assumed was the valve train running. Then I pulled the motor and did all the seals and gaskets including lots of other new things, and didn't do nothing to the head as it was in good condition. After driving the car after the motor was back in I got concerned about the tick as I felt it was a little more defined. I then adjusted the valves where I found that the previous owner tightened them to tight (Am sure they didn't gage it). I adjusted them dead on and the tick is now a defined knocking. Worse when it is cold and barely better when warm. I am assuming that them being adjusted wrong wore something and when I opened that gap it caused slack somewhere causing the knock.
All I need to know is that it is possible just need the right tools and time.
I appreciate your info as some don't provide this much detail and it really puts me into a "pulling the head" mood, but if it is possible which it sounds like your saying it is, then I can do the valve seals with the head on which allows me to do the eccentrics and springs (which is all I am going to do at this point).
I may ask a question like I don't know anything but I do as I have owned four e30's (which are my children, some of which I have adopted out) so far. There is always something new to learn no matter what the topic is and head work is where I lack along with electrical. I am an e30 enthusiast all the way and am determined to learn anything and everything about them.
If you have any suggestions on what could be worn from wrongly adjusted valves causing my tick that is driving me insane it would be greatly appreciated, Thank You!

[1990e30coupe]

You can get the rockers out without pulling the head.

But unless the above means "I HAVE DONE the valve guides and seals..."

Just pull the head.

It'll be a lot quicker.

Have you changed the eccentrics? If they get worn, they can be noisy when you
adjust the valves, as that worn spot now puts uneven pressure on the stems...

t

I was already planning on changing the eccentrics since the way they were adjusted (Wrong) before I got my hands on it. This sounds like it is my issue since the valves were adjusted so tightly.
This is a spot on definition to my knocking issue as I think this is where I will stop and just replace my seals, springs, eccentrics, and hardware.
I know pulling the head will be quicker and I do like saving time, but after collecting a new M20 with 59k and a whole turbo kit pieced over years with legitimate parts, 3 past e30s, two five series, and soon to find a project e30 for my new motor since I don't want to make my daily a project, MONEY is where I am trying to save concerning this child of mine as my next child is what will rob me like all kids do. My E30 is my child and I treat my child very well, but money at this point is tight and if I don't have to buy a new belt, tensioner, head bolts, and spend more time taking more apart and putting together something I have already done I am content with spending more time to do things to the cylinder head that I haven't. You do only what you can do when your financial situation sucks with big dreams, and with my BMW addiction my signature should be IM POOR BUT HAVE TIME for My E30.
I appreciate the input as I think you solved my problem from what I know, hear, and your information. I most likely have bad off kilter eccentrics.
Thanks!

[TobyB]

It's easy, doesn't cost much, and can't hurt...

hope I was right!

t

[master quon]

Understand! If a rocker is loose then what is the cause?

For the M20 head, the rocker arms are held in place by clips that sit in slits on the rocker poles. If the clips are not in the slits, they will move and possibly damage them.

You said the knocking got worse after you adjusted the valves? I'm thinking that could possibly be the issue. My timing belt broke, took off the head to replace the valves and various parts. I adjusted the valves myself (it seems simple enough, right?) When i was done the engine made a lot of ticking/knocking, whatever noise you wanna call it. Took it to the shop and they said the valves needed to be adjusted correctly. I told them i did that already, and this old man whos owned this European shop for like 30 years said he's seen plenty of DIY guys and even some mechanics that dont adjust the valves correctly. At the very least you could do is take it to a shop to see what they think!

[1990e30coupe]

For the M20 head, the rocker arms are held in place by clips that sit in slits on the rocker poles. If the clips are not in the slits, they will move and possibly damage them.

You said the knocking got worse after you adjusted the valves? I'm thinking that could possibly be the issue. My timing belt broke, took off the head to replace the valves and various parts. I adjusted the valves myself (it seems simple enough, right?) When i was done the engine made a lot of ticking/knocking, whatever noise you wanna call it. Took it to the shop and they said the valves needed to be adjusted correctly. I told them i did that already, and this old man whos owned this European shop for like 30 years said he's seen plenty of DIY guys and even some mechanics that dont adjust the valves correctly. At the very least you could do is take it to a shop to see what they think!

Had a master mechanic adjust them with me! I feel doing it in my driveway with him rather than doing it in the service department at the auto dealer he works for (while he would be the same one doing them) didn't make a difference on whether it was done correctly. This is how I found they were adjusted incorrectly from the PO doing it themselves or at a shop they took it to. Couldn't even get a gage in; therefore, I know they were already done incorrectly before allowing them to be adjusted correctly with professional help by my side.
Your at a shops mercy and if anyone is going to screw things up on my ride I would rather be the one to do it. Like you said cant trust all mechanics; therefore, what do you do? How do I know if I take it to a shop that they are telling me the right things? It comes down to trust and these days the only one I trust to touch my ride is myself. I have had horrible mechanic shop experience! Knowing a decent mechanic that I can pick on for info is all I need (which I have) as they are out there far and few between in my book. Other than this because they were adjusted so horribly I feel the eccentrics are worn so I am doing all new springs (outer), valve seals, eccentrics, hardware, and cages. Beyond this if I still have a tick that's beyond the valve train running I will live with it until I have a whole head that is completely done to replace this one
I appreciate the advice, but I disagree with shops as I see better things to do than waste my funds on something I know I can fix. I also don't get a huge bill in the process for parts being replaced that don't need it.
Thanks for the info but adjusting valves is not rocket science that only a mechanic can do. I am sure I am not the only one on here that believes this.
No rudeness just stating my view and fact but thanks!

[1990e30coupe]

It's easy, doesn't cost much, and can't hurt...

hope I was right!

t

I don't see replacing something I just replaced! This is a motto for someone who don't have money and wants to take care of their ride at the same time. Time is also an issue as you may think it takes no time, but removing the head and doing timing belt components will take more time than doing valve seals with the head on (possibly as I have never done it and don't know). You obviously know its possible otherwise you would have stated it is impossible; therefore, I know I can do it! I know it is possible to do valve seals with heads on just not valve guides.
If you read what I posted I am not looking to do something easy as much as I am a time/money saver. I know it wont coast that much more as you are right there, but it is all brand new so if I don't have to replace it by doing a little extra work, which it sounds like your afraid of in order to hope your right, I will do the extra work that may be more difficult or not, have you done valve seals with the head on?
You may be right that it will be the easier route to remove it I will give you that, but it is possible with it on. If I was looking for something easy I would have bought a Honda.
So all I want to know for this post at this point is if doing valve seals with the head on is possible and I have gathered it is, and have also been backed by shop mechanics and others I have asked as it will be tedious and most likely on the difficult side.
Thanks for showing me an easier way as I know it would be but that's not what I am asking!

[1990e30coupe]

Thanks for all the info everyone as I have decided to do the valve seals, outer springs, eccentrics, and cages with the head on. More work and very tedious I would imagine, but in the long run I feel it will be less to tear into/take apart. I will post how it went for overall info for anyone that might ever consider it.
Thanks again!