Newbie starts Valve Spring replacement
Posted by Earendil
They look like half of a gel capsule. It's just a little plastic sleeve that temporarily fits over the tip of the valve stem to give the valve seal a smooth surface to slide down over, rather than risk tearing the seal as it slides over the notches of the valve collet retaining grooves. If you're careful you can re-use the same sleeve for all 12 seals. But, on the assumption that you're going break it, they give you a couple of spares. They were one of the sources of big oil leaks on my old 325e cylinder head. That and a leaky head gasket. They were baked rock-hard on my engine and I was shocked to see how different the new rubber ones felt in comparison. Excellent. Just wanted to make sure you weren't tempted to save money by re-using the old bolts. You'll see when you torque the new head bolts. Those bolts get cranked down to some ridiculous tightness and get stretched to yielding. I can't remember the actual process, it's in the Bentley, but after you torque them down you're supposed to give them each a further 90-degree turn (or something like that). I remember thinking, ya gotta be kidding. I was using a long-handled wrench for leverage and thinking, if this bolt snaps off now I'm going to end up knocking all my teeth out when I punch myself in the face with the end of this wrench.
My gut instinct, because I'm cheap, would be to re-use it. But I'd hate to say go ahead and use it as-is, only to have it break on you later. You've now seen how much work is involved in taking out the rockers. After you've done it once, it's easier the second time. But it would still be a shame to have to do all this work again. If it's already cracked, then of course don't put it back in. If it has a notch cut out of it, or it is scratched, causing a point of stress concentration, then replace it. But if it is merely "polished" smooth, it might even be an improvement. The rockers could last another few hundred thousand miles with no problem at all, or they could break tomorrow. Some people would say now is an opportunity to replace all of them, just because you can. It's up to you. Here's what they look like when they get busted: [i70.photobucket.com] [www.m5board.com] [www.youtube.com] That buildup is just varnish, gummed up old burnt oil. If you can't convince the gunk to come off with solvent, I wouldn't be afraid to use some fine sandpaper to buff it off. You don't want to be scratching gouges into the shaft, just polishing it. Then it should be easy to slide the rockers on or off. It should be possible to replace the rockers individually. You're never going to notice any imbalance in the engine if one is slightly different from the others. |
That one damaged shaft end; It's a plug in there I think- check the parts books, if it's a plug trash that shaft, it's a goner. Any rocker with marks on them I'd toss too; like Ferdy sez, those scratches or marks set up weak spots that break later. Make sure the riding surfaces on the rockers are not flattened out, that goes for the adjusting wheels too. The surface on the rocker face, where it meets the cam should have no bad looking scores or flat spots; you should be able to check this with a visual (you can hold it up to a light, sunlight might be fine) and feeling it with your finger (the fleshy part this time). They sell (I use the Napa kind) a gasket removal spray, it takes a few times but it's a wonderful kind of stuff that works on alloy surfaces- be careful Tyler, use this stuff outside, it's evil shit for your well-being. Wow, I'm seeing the honing marks way up at the top of the cylinder; that's amazing. It just goes to show what Bmw's steel is all about. Small ridge is wonderful Tyler, yes. You are going to put the valves back in the holes they came out of, yes?, it's a good practice if you're using the old guides and valves. Also, feel the tops of the valve stem, sometimes they can be peened over and that makes it rough for the new seal install, even if you have the protectors. One caution on head bolt installation, I use the three stage tightening thing; 1) bring them all, in sequence, up to 30 lbs 2) 60 lbs 3) bring them home and then that "after they're hot thing", these bolts stretch like a mother... Don't forget the light coating of thin oil. Checking the guides; with the valves (hopefully in their same hole) up against their seat see how much wiggle they have*** illustration*, make a fist and slide a pencil in so a good part of it sticks out one side, take the end of the exposed pencil and wiggle it at its end. This is basically the type of test it is. Now, back to our regular scheduled broadcast. After you've tested for the slop with the valve in the closed position pull it out and test it where it would be when the valve is open, and then a touch further just for good measure. Some how we are going to agree on an allowable wear range on this but first give me what YOU think you have and then we'll get a little closer to what you actually have- this is going to be hard over the computer but lets give it a try... Rick |
Got it.
I'll pop into my small local Napa after work and see if they carry such a thing. I wouldn't have guessed that they made something specific to removing gasket!
Yes, I'm making sure all parts that aren't being replaced go back into their original location.
I guess I'd have to double check, but this procedure appears to be quite different from what is in the Bentley for the M20. If it is different, could you explain why you suggest your method?
Okay, I tested all valves in their original guides as I was removing them this morning. All valves have little to no play "side to side" (direction parallel to the camshaft), and they all have under 1.0 mm of play "up and down" (perpendicular to the camshaft), with the majority having closer to 0.5 mm of play. Note that these measurements are not on the stem side, but on the cylinder side. Is this within a limit that you feel good calling it one way or the other, or should I attempt to take a video of it? I'm taking Friday off work to start putting it all back together, hopefully increasing the chance that my baby will be back by Monday. ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles 
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Tyler sez
Okay, I tested all valves in their original guides as I was removing them this morning. All valves have little to no play "side to side" (direction parallel to the camshaft), and they all have under 1.0 mm of play "up and down" (perpendicular to the camshaft), with the majority having closer to 0.5 mm of play. Note that these measurements are not on the stem side, but on the cylinder side. Is this within a limit that you feel good calling it one way or the other, or should I attempt to take a video of it? I'm taking Friday off work to start putting it all back together, hopefully increasing the chance that my baby will be back by Monday. Yes, side to side is what we're testing (wiggling the valve stem in the guide back and forth). You need to check the play both when the valves are closed and the open position. 1mm sounds excessive, the play should be all most imperceptible for a seal to hold oil from getting in to the cylinder but, you might have to chance it- oil the stems up good when you're assembling. I usually put a little white grease on the protruding valve stem (once the valve is in place in the head) so the seal does not run dry on start up. Grease is a great way to hold things in place too, like valve keepers and such, watch your fingers 
If you didn't have a smoking condition (out the exhaust) from loose guides to start with (and you would know if you had) you'll probably be fine with those clearances. Rick |
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Awesome, I would take a day off work (tomorrow) and end up getting sick (yesterday) :?
I did however start on the reconstruction tonight. I put all the new valve seals in! yay! I also attempted to get the left over gasket off with gasket remover that I bought at Napa... no effect. Hours of soaking, multiple soaks, nothing. I guess I'll take the chisel to it one last time and see if I can't do more harm than good. There isn't a lot left, but there is more gasket material there, than there is head material I would accidentally remove with a chisel, so I suppose that makes it a good idea... That is one very poorly constructed sentence, but I'm tired and sick and can't think how to fix it. For tonight I just have one question really. After a delay in the shipping, I finally got the "head gasket kit". I knew what everything was just by looking at it (I was good at shape matching as a baby!), except for the following pictured items. Note that the quantity is also accurate, and I tossed in a match box for size comparison. Ideas? Note that the metal rings come in two different sizes. I haven't the foggiest where any of this goes. [w3.gorge.net] I'll have a good long update tomorrow night or saturday. ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles Edited 1 time(s). Last edit at 03/25/2010 08:24PM by Earendil. |
When the valves are in the closed position they are rock solid with no movement. The distance I quoted was the distance at full open, or a bit past, at the cylinder end. i.e. all movement would have been exaggerated. On the valve stem side the movement would have been closer to 0.1-0.2mm if any at all.
This is where an automotive background would keep me from asking stupid questions. What kind of grease would I use for this?
Nope, no smoking condition, and I'm relatively sure that all my oil loss was out the sides of the engine and not the tail pipe. Any problem I may have had should be further mitigated by new valve stem seals. The old ones were hardly made out of anything that could be considered rubber any more! ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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Well, from what you say the guides should hold up fairly okay, just hope for the best and being all the valves went back in their respective guides is a plus. The grease you usually use for a front end is fine for valve keepers or small light stuff, I have fiber grease if I need to hold bearings in a race that has to get turned every which way on install though. Thrust washers in transmissions have to be gasket shellacked in place, grease is not enough to hold them in place when you're installing a lay shaft/cluster gear assemblies. Rick |
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Okay, my update is lacking fun pictures and a conclusion, so I'll keep it brief for now.
I was sick all weekend, but that didn't keep me from trying to complete. Put most everything back together on saturday, everything that didn't require a torque wrench. Sunday morning I finally got the torque wrench, and it finally started raining. So with a giant trash bag over the hood, I started on the head bolts. In the Bentley specified order: 22 ft-lbs done. 90 degree turn done. second 90 almost done. My E14 torx socket broke in half on the #10 bolt. @#$% :X Fortunetally there is ONE place in the gorge that sells an E14 torx socket, though it's Napa, 45 minutes away, and it was 4pm on a sunday. So today I'll go pick that up. The bigger problem I have is that once I get it, I'm not sure exactly how far I was on the #10 bolt before the socket snapped. I guess I'll just undershoot. Undershooting is far better than over torquing, right? Once I get those down, I'll put the coolant in, reattach the exhaust pipes to the manifold, new spark plugs put in, and she should be set. I'll be recording the start up, so that if she bursts into flames I at least have a good video to show for it. The only other issue I'm aware of is that I might have swapped the fuel in and return hoses. But the only problem with this is that the engine won't get fuel, right? The regulator won't flow in reverse, so the worst that I think could happen is that I burn out my fuel pump if I leave it going for too long. I'm hoping that it's obvious in one of the pictures I took that I have at home which is which. It just occurred to me that I could hotwire the pump and make it pump fuel, that should tell me pretty quick which one is which 
On second thought, maybe it wouldn't be a bad idea to remove the fuel lines when I first start her up. The starter will crank the engine without firing, potentially revealing problem before high explosives are involved, and this should also tell me which fuel line is which. Yes, I'll be safe with the fuel lines if I do this ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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Yeah, I thought so
I have the new style, it was raining, the car is parked on gravel, and the passenger side is jacked up so I can get to the exhaust manifold easily. That's why I didn't trace it back... but maybe I will.
I have a couple gallon jugs left over from mixing new coolant. I can stick the hoses in there and be pretty safe...unless I take up smoking between now and then. ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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We're going to do this in the good news/bad news style of story telling.
The good news. Despite mother nature deciding to SNOW on me while I wrapped up my car last night, I managed to do it. After charging a dead battery, my car fired up after 3 or 4 cranks. For some reason I was expecting either a ball of flame, or the sound of a Ferrari engine. I got nothing so exciting. The engine ran rough and sounded different, which I was expecting, but it continued to sound different after a minute, which I was not. However the idle was spot on 700 rpm without a noticeable change in the needle. I gave her a little gas but met major hesitation up to 1800 rpm or so. After a while I got up the guts to go higher because I wasn't hearing metal sounds yet. After 2000 rpm the engine smoothed right out. However it hesitated below 1800 again when dropping down. I tinkered some more, checked for leaks, and finally decided to start her back up and go for a drive. One should never get emotionally attached to a car, because as I slowly pulled her out onto the road, I couldn't help but think this could be the last time I drive her. Between being nervous that I'd hurt her, the initial gravel road (can't hear the engine) and the fog, I went really easy on her. However I wasn't having driveability problems around 1000rpm. When I hit the paved road the engine sounded fine, again with no problems. No warning lights, engine temp is up, so I decide to push her a little bit. She climbs up to 3000rpm without a problem. I couldn't say if all her power was there. my loaner car has been an 84 chevy S-10 (with all of 94hp), and I never hit WOT. However, nothing sounded out of place. After that 8 minute drive I brought her home, let her idle, notice no hesitation problems at low RPMs, and checked her over again. This is when I noticed... The Bad News. There is way too much white "smoke" coming out the tail pipe. It was probably there the entire time, but it was cold and I was working by flashlight, so I didn't take note. I went ahead and drove it 15 minutes home trying to convince myself that I can't possibly be blowing coolant past my brand new seal. I started it this morning, and there was hardly any white exhaust out the tail pipe...than she warmed up, and it started. @#$%. The only problem on installation that I had was with that one head bolt, which on its second set of 90 was probably only turned 75-80 because I wasn't sure where it was at when my socket broke. I'm going to try and bleed the air out of the system one last time after work, and make sure the coolant is at the proper level. At this point I should be able to tell for sure how much coolant I'm eating. My understanding of vaporizing coolant is that it HAS to be the head gasket, right? The car runs as well now as it did before removing everything, but I haven't tried pushing her too hard. Being sick and spending half of last night awake and coughing hasn't improved my mood much either... I don't want to take her apart again 
The only thing that makes me feel the least bit happy is that the engine is really pretty right now. It's a stupid thing to feel good about, considering, but it's about all I have. *sigh* So right now I think the plan is to take it all back apart. Double check the timing belt to see if that could have caused the rough lower idling, and put another head gasket on. Unless someone can suggest other things to try or do before that... ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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Been doing some reading and thinking... I suppose I could have cracked my head somehow, aye? Maybe I'll do a compression test and see what that reveals. I can also check spark plug colors when I'm doing this. After about 20 minutes of total driving, I didn't see coolant in the oil, or oil in the coolant last night. I'll double check that again too.
----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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Now I'm more scared, and a little confused. The biggest headache and pain for me, is not knowing how this is all going to turn out.
So I took it for a 2.5 mile drive up and around a hill during lunch. Before starting the car, I checked the dip stick and oil cap for signs of coolant, none found. Checked my coolant level, and made sure it was spot on. Bled the system of air one more time, and took off. Car appeared to drive fine, but again I didn't push her. Temperature rose and stayed spot on the entire time. While driving I couldn't see white smoke behind the car, but it's sunny and 55 degrees, and I was going 25-30mph. When I got back, I parked but left the car running so I could check the tail pipe. Nothing visible coming out. I revved the engine to 2000rpm and still nothing out the tail pipe, but I did notice it's now running pretty rough! So I turn the car off, and check all the same spots again. Coolant level, good. Dip Stick, clean. Oil cap, @#$%. Nothing visible inside, but on the bottom of the cap there it was, a little white residue. So now I'm confused. I can't imagine why the coolant/oil mix didn't show up until now on the cap, but why the sudden lack of coolant out the tail pipe? I don't think I'll be running the car any more, not with the possibility that the oil is compromised. I guess I'll also pop the valve cover off and make sure all the head bolts are still there ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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That residue doesn't mean anything by itself. It's time to take a couple of deep breaths, or do whatever it is you do to calm down. It's NOT time to go taking the car back apart. There's probably no reason for that. I wouldn't change the oil either. I would just use the car for short trips and see how it all goes. If you do have a problem, you'll know soon enough to avoid any major damage. Keep an eye on the oil and coolant. If they stay clean and unmixed and the car runs fine, then go for longer trips. Everything is probably OK. |
Thanks guys, you're always the slow to judge, quick to wisdom. You all may very well be correct. I pulled the valve cover and inspected everything under it to the best of my abilities. Nothing out of place, and no sign of coolant. I pulled all the plugs and checked their gap again, and their condition. Most of them were brownish, and at least one of them had buildup across the gap. Note that these plugs had about 12 miles on them. It is, as I think about it, highly likely that the tail pipe collected all kinds of sh*t while I was cleaning the engine. In fact if I think about it, when I went to clean the bolt holes with a compressor and hose, I found out that I had failed to drain the coolant from the block, and only drained it as far down as the pump. This resulted in the engine and myself getting a nice coolant shower as the air forced into one side of the block, moved the coolant out the other. It's quite likely that the tail pipe which is right there, and angled up, captured a bunch of this. I also did a compression test, which though I wouldn't bet my life on the accuracy of my cheap gauge, it is surely accurate when measured against it's self. In PSI, I got 145-140-145-140-145-145 So with that done, and nothing coming out the pipe, I drove 8 freeway miles to a friends house and back. No sign of coolant on the return. I now only have two problems, which I could attribute to any number of things, and perhaps should start a new thread. But I'll mention them here. First, I kept getting the 1221 oxygen sensor fault. I think I read someplace that excessive rich conditions can flat out kill the O2 sensor. What about excessive everything-I-dumped-in-the-engine? A good sniff at the tail pipe says that I am NOT running rich, so unless I'm running lean, perhaps the O2 sensor is toast? Second, if the car is at idle around 600-700 RPM it's fine. If I turn the lights on, a squeaking/swooshing sound develops in the engine bay. It sounds *almost* like a belt, but not as high pitched. I know enough about electricity to know that the only thing mechanical that happens when I turn the lights on, is that the Alternator has increased resistance, but would that cause the belt to squeak? Or perhaps my alternator is going out? Of note, as soon as the RPMs climb to the point where the alternator should up the voltage, the squeak/swooshing goes away. I'll dig out the multi-meter tomorrow and make sure the voltage in the car is correct. I *think* at this point I can say that my engine is okay. I was kind of surprised when my car started right up without any problems the very first time. I was sure with all the digging and touching of ancient parts that I would break a wire, or bump a sensor the wrong way. Perhaps it's time to do a full sweep of the sensors and wiring again! Pictures soon... ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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Thank you everyone who had advice or kind words for me during this very trying experience. Seriously, from the bottom of my heart.
A fellow software engineer who has a car mechanic as a brother told me today that he can't stand working on cars. I told him that I didn't much like it either, but I *loved* learning, and would do anything at least once if it meant better understanding the complicated devices in my life. So while I fully enjoyed this, I think I'd like to graduate to an advisory position, and not tear down my engine again for some time
Thank you all once again. Long live BENN  ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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Black + Clear coat Spray Paint: $10
Time spent painting while waiting for other things: 15 minutes Looking at a shiny engine, that can be cleaned with a wet rag: Priceless. [w3.gorge.net] [w3.gorge.net] And the manifolds are now reattached to the head. [w3.gorge.net] [w3.gorge.net] [w3.gorge.net] Tuesday night. I really wanted to get done with this!! [w3.gorge.net] [w3.gorge.net] Sorry, there is no video. By the time I started her up it was near dark, and nothing I had would take a video in that light. More pictures to come. ----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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Hey Tyler, That picture of you in your rain gear strikes me (been there) and is especially cool (it's all about dedication) 
Like the guys are saying about the 02 sensor is true. The belts (even if they were new before the valve job) maybe be dirty after all your cleaning so they might have to be dealt with at some time soon. Taking charging readings is a great idea. All that black looks good, you used a satin finish, yes? I know what you mean about taking your car apart; when mine is I'm a bit cranky... Well done
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That's awesome!
Sure there was some money involved in the bits and pieces and tools required. And sure, an experienced mechanic could have done this with his eyes closed in half the time it took you to do it. Okay so that work would have come with a guarantee and warranty so you wouldn't have to worry. But for sure it would also have come with a shocking bill of at least $1,500 or more. Nothing replaces the satisfaction of knowing you did it yourself, and you took the time to give it some love by cleaning and painting stuff. Now you have truly bonded with this car. Hats off to you dude! We're all proud of you and cheering! |
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The Saga Continues...
----------------------------------------------------------------------------------- 1989 - E30 - M20 - Manual. Approximately 270,000 miles 2000 - E46 - M52TUB28 - Manual. Approximately 110,000 miles
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