Loose head nut?

[e34.535i.sport]

Hi there, long story short i popped the bonnet just now to find one of the head nuts had a small pool of oil around it, and its not the first time this has happened... checked around the head and everything else is fine (gasket looks sound - no choco milkshake or oil loss etc), so i tightened the nut up about half a turn (maybe less).

With hind-sight i'm hoping it was ok to do this due to the torque of the but and whatever - if i'm honest i know very little about the engine and its workings, so did i do the right thing? If not any advice on what i should do next?

Thanks guys.

[DaveVoorhis]

Sounds like you tightened a valve cover bolt. The head bolts are under the valve cover. It should be fine, but if it continues to leak it's probably time for a new valve cover gasket.

[whiskychaser]

Hi there, long story short i popped the bonnet just now to find one of the head nuts had a small pool of oil around it, and its not the first time this has happened... checked around the head and everything else is fine (gasket looks sound - no choco milkshake or oil loss etc), so i tightened the nut up about half a turn (maybe less).

With hind-sight i'm hoping it was ok to do this due to the torque of the but and whatever - if i'm honest i know very little about the engine and its workings, so did i do the right thing? If not any advice on what i should do next?

Thanks guys.
Think what you mean is the cylinder head cover cap nuts. Stand to be corrected but you normally start tightening in the middle and work your way out. Sure someone can put you right on the torque but meanwhile I dont think you have anything to worry about

[e34.535i.sport]

The cylinder head nuts sound like what they'd be... They're on the top of the head about 6 or 8 of them?

I just tightened the one, as the others seem fine... The one i tightened wasn't very tight, i could do it with a stubby 3/8" ratchet so i'll have to check out the torque spec's on these ones. Anyone happen to know them?

Thanks peeps...

[DaveVoorhis]

Yup, you've definitely tightened a valve cover nut. You can't see head bolts without removing the valve cover.

[e34.535i.sport]

Hey haven't been able to check on this for a while as i've been off the road for a while with coolant hose issues! Thats sorted now so i took her out for a spin today and it felt amazing. However, got another tiny pool of oil so i let her run and wiped the pool away. The oil was seeping very very slowly through the bolt above the washer which i though was unusual? Is this a headgasket problem as i don't have any choco milkshake stuff in the oil and the coolant seems ok (only changed it recetly though)...

Please help i'm worried.

I want to tighten the valve cover nut more as it seemed loose but i don't want to make things worse...

[e34.535i.sport]

Its one of the number 6 nuts that goes through closest to where number 1 and 5 are...http://www.realoem.com/bmw/diagrams/a/k/10.png

[DaveVoorhis]

That's a valve cover nut. Your valve cover gasket (#5 in the diagram) is starting to leak. It's easy to replace, and it'll be a good opportunity to adjust the valves and inspect the valve train for sludge and wear.

[whiskychaser]

Hey haven't been able to check on this for a while as i've been off the road for a while with coolant hose issues! Thats sorted now so i took her out for a spin today and it felt amazing. However, got another tiny pool of oil so i let her run and wiped the pool away. The oil was seeping very very slowly through the bolt above the washer which i though was unusual? Is this a headgasket problem as i don't have any choco milkshake stuff in the oil and the coolant seems ok (only changed it recetly though)...

Please help i'm worried.

I want to tighten the valve cover nut more as it seemed loose but i don't want to make things worse...
As you can see the link cant work like that but I'm certain its not a head bolt. What you are looking at is just a cover over the camshafts. If there is room, try putting a fibre washer under the steel one. That should stop the oil seeping. If the nut keeps working loose, clean it and the bolt threads, put on a drop of locktite and tighten again

[e34.535i.sport]

As you can see the link cant work like that but I'm certain its not a head bolt. What you are looking at is just a cover over the camshafts. If there is room, try putting a fibre washer under the steel one. That should stop the oil seeping. If the nut keeps working loose, clean it and the bolt threads, put on a drop of locktite and tighten again

Hey does this link work:

http://www.realoem.com/bmw/partgrp.do?model=HD12&mospid=47382&hg=11&fg=15

Its the top diagram one of the nuts on there... Is that what you imagined?

[whiskychaser]

Hey does this link work:

http://www.realoem.com/bmw/partgrp.do?model=HD12&mospid=47382&hg=11&fg=15

Its the top diagram one of the nuts on there... Is that what you imagined?
Yep that link works fine. Its just what I thought. It occurs to me that if its a domed nut, you could be tightening it as far as it will go but it still wont be tightening down to the cover. Thats how the oil could be getting out. If thats the case a fibre washer should definitely sort it. Hope that helps

[leicesterboy15]

Cylinder head cover and valve cover are the same thing, definately sounds like a valve cover bolt. Defo won't be a head gasket issue. The torques should be in the bentley manual. The valve cover gasket is a perishable item so its nothing to worry about, I've had mine replaced recently.

[e34.535i.sport]

Whisky - Just to make sure can i take the bolt completely out, put a fibre washer on under the metal one and then torque it bcak up without messing anything up?

Dave - I'd love to get in there but it looks a little out of my league, i've never dealt with engines before. I have suspicions of sludge as when i do an oil change it only takes 5 Litres, when it should take 5.7 Litres. What would you do? Is it something an amateur (I'm new to this but committed) can do? If so how long would it take and at what cost? Sorry for all the Q's. Oh one more, is this what everyone calls the headgasket or is that somewhere else?

[whiskychaser]

Whisky - Just to make sure can i take the bolt completely out, put a fibre washer on under the metal one and then torque it bcak up without messing anything up?

Dave - I'd love to get in there but it looks a little out of my league, i've never dealt with engines before. I have suspicions of sludge as when i do an oil change it only takes 5 Litres, when it should take 5.7 Litres. What would you do? Is it something an amateur (I'm new to this but committed) can do? If so how long would it take and at what cost? Sorry for all the Q's. Oh one more, is this what everyone calls the headgasket or is that somewhere else?
From the diagram it looks like you have a domed nut that screws down on a stud. It doesnt matter either way. Just put on the extra washer. You cant do any damage unless you go crazy tightening it. The head gasket is number 2 in the bottom diagram of your link. I dont know the spec for your engine and dont want to insult your intelligence but the the oil filter holds some oil too. That may be the difference though I would think when you change your oild you change your filter too

[DaveVoorhis]

Dave - I'd love to get in there but it looks a little out of my league, i've never dealt with engines before. I have suspicions of sludge as when i do an oil change it only takes 5 Litres, when it should take 5.7 Litres. What would you do? Is it something an amateur (I'm new to this but committed) can do? If so how long would it take and at what cost? Sorry for all the Q's. Oh one more, is this what everyone calls the headgasket or is that somewhere else?
As Whiskychaser says, the difference in oil quantity is probably what's in the oil filter, plus whatever drizzles and puddles are still in the engine shortly after it's run.

Changing the valve cover gasket and adjusting valves is certainly something a committed amateur can do, if said amateur has a modicum of mechanical aptitude. If you're good at fixing gadgets, you'll have no problem with this. If, however, you're the sort that finds changing the lead in a mechanical pencil beyond you, and you've thrown out five toasters because you didn't dare pull the crumb tray, then this might not be for you.

This is not the head gasket. This is the valve cover gasket. The head is bolted to the block, and seals with the head gasket. Changing it, if needed, is a relatively big job. The valve cover is bolted to the head, and seals with the valve cover gasket. Changing it, if needed, is an easy job. Just changing the valve cover gasket takes mere minutes if you've done it before. Changing it and adjusting the valves will probably take you a couple of hours the first time.

Get the Bentley manual -- it tells how to adjust valves, among other things.

[e34.535i.sport]

Cheers guys, the information is much appreciated. GOing to get a fibre washer now see how that goes... I'm thinking i might do the valve cover gasket anyway as there must be a problem for it to be leaking?

It sounds like i have a good chance of doing it... I am a teacher so i have lots of patience (sometimes!).

Report back later...

Again, many thanks.

[e34.535i.sport]

Hey i got a rubber washer from BMW, will put it on once i find these things out!!!! Does anyone know...

1. What torque will i need to reset the bolt to?

2. Do i need to undo all the bolts and retorque them?

3. Am i simply ok to remove the bolt, put the washer on and then put it back in and retorque it or is there any other special things i need to do?

Thanks... This stuff scares me.

[whiskychaser]

Hey i got a rubber washer from BMW, will put it on once i find these things out!!!! Does anyone know...

1. What torque will i need to reset the bolt to?

2. Do i need to undo all the bolts and retorque them?

3. Am i simply ok to remove the bolt, put the washer on and then put it back in and retorque it or is there any other special things i need to do?

Thanks... This stuff scares me.
1. 10nm
2. No
3. Just start in the middle and check all the bolts are tight.
Dont go mad and break a stud. 10nm isnt a lot

[e34.535i.sport]

1. 10nm
2. No
3. Just start in the middle and check all the bolts are tight.
Dont go mad and break a stud. 10nm isnt a lot


Many thanks... I have a torque wrench but it only operates in the range 40-200nm.

My studs seem to have metal washers underneath them, but in the diagram BMW have it doesn't show any, so i'm not sure if the PO has had them put on for some reason... However, the engine runs fine besides this tiny leak. Although the leak seems to be getting worse. Will try and undo the nut tomorrow and throw the rubber washer on the bottom. Fingers crossed ay.

[DaveVoorhis]

Dont go mad and break a stud. 10nm isnt a lot
Yes. Beginners frequently make the mistake of using too small of a wrench when removing things and too big of a wrench (and too much force) installing them.

This might be a good time to consider buying torque wrenches. If you're going to keep working on cars, you'll need them. Buy an inexpensive heavy-duty 3/4 inch drive wrench for lug nuts and other big stuff, and a good quality 1/2 inch drive wrench for small fasteners, like valve cover nuts, throttle body nuts, intake nuts, etc.

[whiskychaser]

Yes. Beginners frequently make the mistake of using too small of a wrench when removing things and too big of a wrench (and too much force) installing them.

This might be a good time to consider buying torque wrenches. If you're going to keep working on cars, you'll need them. Buy an inexpensive heavy-duty 3/4 inch drive wrench for lug nuts and other big stuff, and a good quality 1/2 inch drive wrench for small fasteners, like valve cover nuts, throttle body nuts, intake nuts, etc.
If you are buying a torque wrench, suggest you get one that has a certificate of accuracy. May cost a little more but without it you still wont be sure of the actual torque you have/have not applied

[Ferret]

If you are buying a torque wrench, suggest you get one that has a certificate of accuracy. May cost a little more but without it you still wont be sure of the actual torque you have/have not applied

I got given one of these (http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_17 8843_langId_-1_CarSelectorCatalogId__CarSelectorGroupId__varien t__categoryId_76866_crumb_33958-76859_parentcategoryrn_76866) for christmas last year - well impressed with it, it's not cheap but it's really accurate and feels good quality.

Wouldnt normally buy their kit, but this one might be worth it :)

If you're strapped for cash, these might be a better option:
1/4" (http://www.screwfix.com/app/sfd/cat/pro.jsp?id=29953&ts=20587)
1/2" (http://www.screwfix.com/app/sfd/cat/pro.jsp?id=44700&ts=20587)

Screwfix are a top notch company, in my experience - their customer service is second to none.

[e34.535i.sport]

Hey i have the same halfords professional one but its bigger and does between 40 and 200nm... I've found it really to be of a really high quality too. Will have to invest in the smaller one before i start messing with the valve cover nut i think.

Thanks for the advice, i'll prob go with the Halfords professional one for the lower torques.

[e34.535i.sport]

Just to chack, can i replaced the valve cover gasket without adjusting the valves?

What purpose does adjusting the valves serve, and is it worth doing while i have it open? I don't really want to leave it open for too long though as i will be working on the drive, and i wouldn't want anything unpleasant getting in there.

[whiskychaser]

Just to chack, can i replaced the valve cover gasket without adjusting the valves?

What purpose does adjusting the valves serve, and is it worth doing while i have it open? I don't really want to leave it open for too long though as i will be working on the drive, and i wouldn't want anything unpleasant getting in there.
Yes you can replace the gasket without adjusting the valves. The cover is there to keep the oil in and your fingers out:) But as Dave said, while its off you may as well check them -its always best to fit a new gasket each time you take something apart. Adjusting the valves takes up slack due to wear.

[e34.535i.sport]

You're clearly very knowledgeable on this subject, and i can't thank you enough for sharing it with me (both of you!!!!)...I apologise for my lack of knoweldge in the area, i haven't been able to download the bentley yet... I normally like to read up thoroughly on any jobs i do before i do them. This one has been sprung upon me so to speak!!!!

I'll look into the valve thing i think, sounds like it would make the car even nicer to drive. Providing it doesn't require any expensive specialist tools to do i'll give it a go.

Now for the bentley download...

[Ferret]

You're clearly very knowledgeable on this subject, and i can't thank you enough for sharing it with me (both of you!!!!)...I apologise for my lack of knoweldge in the area, i haven't been able to download the bentley yet... I normally like to read up thoroughly on any jobs i do before i do them. This one has been sprung upon me so to speak!!!!

I'll look into the valve thing i think, sounds like it would make the car even nicer to drive. Providing it doesn't require any expensive specialist tools to do i'll give it a go.

Now for the bentley download...

Question!

Is the engine fairly quiet (no ticking) and smooth at idle? Is it returning reasonable mpg for the age and size of engine?

If so, I wouldnt touch your valve clearances untill you've 100% read up about it, got the proper feeler guages and it's already running like crap... messing with the clearences on an M30 when the engine already runs good is a false economy in my book, as they can cause all kindsa problems when disturbed...

[e34.535i.sport]

Question!

Is the engine fairly quiet (no ticking) and smooth at idle? Is it returning reasonable mpg for the age and size of engine?

If so, I wouldnt touch your valve clearances untill you've 100% read up about it, got the proper feeler guages and it's already running like crap... messing with the clearences on an M30 when the engine already runs good is a false economy in my book, as they can cause all kindsa problems when disturbed...

I'd have to say its pretty good. Its relatively quiet until i put my foot down, no ticking but i got a rough idle. This is one thing that doesn't bother me though, i see it as the car massaging me on the way to work! :p

Overall the car runs well, and still has a good deal of power. The gasket actually looks good from the outside (from what i can see), as though it has been changed in the past (relatively recently). After doing some detective work other things point to this being the case too - as the valve cover nuts all have metal washers underneath which i here helps prevent the gasket from leaking.

First thing i'll try is the rubber washer under the metal one and retorque... If the leak still occurs i'll change the gasket. I might leave the valve clearences then until i'm a bit more confident engine-wise because it honestly scares the crap outta me. I don't mind messing with suspension, i'm confident with that now. This will be my first encounter with the engine though, so best to walk before you run.

I read that you should retorque the bolts from the middle outwards, can anyone elaborate on this? Does it mean if i take this one bolt out i'll need to loosen all the others and retorque them? From the middle outwards, does this mean do the top middle then bottom middle, then the ones either side of these until i reach the sides? (Looking from the side of the car?)

I hate being confused.

[whiskychaser]

I read that you should retorque the bolts from the middle outwards, can anyone elaborate on this?
The objective is to pull the cover down evenly-bit like nailing down a wonky floorboard
Does it mean if i take this one bolt out i'll need to loosen all the others and retorque them?
That would be best
From the middle outwards, does this mean do the top middle then bottom middle, then the ones either side of these until i reach the sides? (Looking from the side of the car)
Thats it in a nutshell

[Ferret]

I read that you should retorque the bolts from the middle outwards, can anyone elaborate on this?
The objective is to pull the cover down evenly-bit like nailing down a wonky floorboard
Does it mean if i take this one bolt out i'll need to loosen all the others and retorque them?
That would be best
From the middle outwards, does this mean do the top middle then bottom middle, then the ones either side of these until i reach the sides? (Looking from the side of the car)
Thats it in a nutshell

Torque the cover up something like this: (first person to say 'but that's an M20..' I know and you should be shot.)
http://i11.photobucket.com/albums/a190/Ferret101/Car/M20-Rocker.jpg

If you intend to do the whole gasket, you've got to pull off the air metering kit, here's how (points 8 to 10):
http://i11.photobucket.com/albums/a190/Ferret101/Car/M30-hr-2.jpg

[e34.535i.sport]

Torque the cover up something like this: (first person to say 'but that's an M20..' I know and you should be shot.)
http://i11.photobucket.com/albums/a190/Ferret101/Car/M20-Rocker.jpg

If you intend to do the whole gasket, you've got to pull off the air metering kit, here's how (points 8 to 10):
http://i11.photobucket.com/albums/a190/Ferret101/Car/M30-hr-2.jpg

Hey thanks for going to all that trouble, its very useful. That air meter thing is making a rattling noise anyway so hopefully taking it off and re-securing it will sort it! I hate any unnecessary noises when driving, especially rattle type ones. Thanks again!