E46 Fanatics Forum banner

Headgasket Replacement

22K views 18 replies 10 participants last post by  Barrsurf 
#1 ·
I am planning to change my headgasket on the 328i M52TU engine, and wanted to know if there is anyway to do it without having to remove camshaft or the valves?
 
#2 ·
Why do you need to change the head gasket? It's very rare that they fail for no reason.

If it overheated and the head gasket blew, have you attempted to re-torque the head bolts to make sure they'll still hold torque?

If the engine overheats, there is a distinct possibility that the head will warp, and the head bolt threads in the block will be damaged. If this is the case, your replacement head gasket will be an enormous waste of time and money, since you won't be able to torque the head back down once you've done all the work.

... not trying to be a buzzkill, just tryin' to save you some frustration down the road.
 
#3 ·
Nathancarter,
Thanks for your posts and your input. My car overheated, but i pulled over immediately, and got the car later towed back home. I drove maybe for a mile, and then it overheated. When i open the coolant expansion tank, there is gas fumes and the coolant bubbles (most likely caused by a bad bad head gasket).

I have not attempted to re-torque the head bolts yet, because i have not began the head gasket job. I was wondering if you have done a head gasket job? or if you can answer my original post's question. If the head is warped, and i wont be able to torque the head back down, then i would probably buy a new head.
 
#4 ·
why don't u test it first?? pressure test it with the plugs out and see if the cylinders fill with coolant.

last i checked the headgasket was under the head so i think the head does have to come off... :hmm:
 
#8 · (Edited by Moderator)
I hope you're not offended, but I'll publicly reply to your PM so that everyone can use the info:

For the compression test, you need a special tool. Here's an example, courtesy of Ken:
http://www.whatsyourconcept.com/itemDetails.asp?itemID=696
and some general (non-E46-specific) information on performing the test:
http://www.search-autoparts.com/searchautoparts/article/articleDetail.jsp?id=16170


For the service bulletin regarding the head bolt torque test:
http://forum.e46fanatics.com/showthread.php?p=7381565#post7381565

Note that by doing this you are testing the BLOCK'S ability to hold onto the cylinder head. If the results of this test are bad, then a new/different/machined/repaired cylinder head will not solve your problem, because you won't be able to mount it to the top of the block. You MIGHT be able to repair the block with a TimeSert or Heli-Coil or similar re-threading tool: though BMW doesn't officially support it, there are folks on this forum who have done it.

And, one more link with extensive (but not absolutely flawless) instructions on removing the head from a M52tu:

[Mod edit: link no longer available]
 
#9 ·
Thanks again for all of the info and nathancarter, i was not offended at all, and value your input.

old'n'slow, you answered the question for my original post, but the additional posts helped clearify different things as well.

I am going to go all DIY, and hopefully i can find my camera (i think i missed placed it), and hopefully once my MCATs are done in May, i can write a DIY with pics on a headgasket job, because i searched everywhere and the closest thing i found (but it was pretty much without pics) was the link that nathancarter sent from ezflatscreen.com......
 
#12 ·
i already have bought a bunch of bmw special tools, i believe i have all of the required tools for it.

I am probably going to begin on this project on friday and hopefully i will be done by sometime in sunday.

I had read somewhere, that one guy had stated that you must machine the head, or the head gasket will not work? Is this just for safety, or will it truly not work if its not machined? I know it wont work regardless if the head is warped, but i barely drove on it, when it began to get overheated. The only reason im doing the headgasket job is because when the expansion tank is open there is gas fumes coming and it is bubbling. I have emptied the oil and the coolant, and they both appear perfectly clean. I am hoping that i do not need to machine it, just because the dealership around us does not do machine the heads during the weekend (their head mech is never there on weekends) and if i do this, i must remove the cams, valves etc. and put them back together which would make this job much longer.

IF any one has done this head job and they have done it without machining the head, please let me know, because that would make a lot of my doubt disappear. thanks again
 
#15 ·
You have all the vanos tools and crank pin holder?(you will need the cam plate tool) As well as the timing chain tensioner block and tool? GL and no the head does not always have to be machined. Check the head bolts before removing to make sure otherwise you will have a nasty supervise when you go to reassemble!
 
#16 ·
thanks for the post you guys. I have bought all the tools stated above, most of them coming from pelican parts even have the timing chain pretensioner as well. Im going to do this job without having to machine the head, and will keep my fingers crossed, but i dont believe that it should be all that bad. I will def. check the head bolts to make sure their fine, if not then ill be a bit pissed, but will try to fix it. Will keep you guys posted
 
#18 ·
Make sure you replace not re-use your head bolts, since the m52tu is an aluminum block with iron sleeves vs cast alloy iron/nickle block of a m52, the head bolts are stretch bolts which is why the torque spec is 25 foot pounds then 2 90 degree rotations past that effectively stretching the bolts. If you do no replace the bolts you will strip the threads in your block on at least one of them as you replace them. Considering the bolts cost all of $30 its worth replacing them anyways.
 
#19 · (Edited)
This is one thing I'm struggling to understand. The bolts are designed to deform at torque. But the BMW service bulletin, and I've heard from others, says to loosen and re-torque to see if the block holes are still viable. So even though the bolts have been stretched you can still re-torque back to spec? Do you do the 25 ft lbs and then the 2 90 degrees again? This is what I'll be doing this Easter weekend. YAY!:censor:
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top