metal or paper timing case gasket?

[Sellick]

Just started reassembly of my engine and realized that I have two gaskets (one steel and one paper) that go between the timing chain case and the block... do I use both? I'm not seeing anything about two gaskets in the manual or online. RealOEM lists the steel gasket, but nothing about the paper. It seems strange to me to use both. If I'm supposed to pick one, is one better than the other?

[Sellick]

Further research is showing just one gasket, which suggests that the gasket kit just came with two different styles. I don't like the idea of a metal gasket, so I'm planning on going with the paper + gasket sealer. If someone knows that the steel gasket is a million times better than paper + sealer, please let me know.

[colin86325]

I think the metal gasket was intended for M44 engines.
When I rebuilt mine I deleted the gasket and used Yamabond instead.  No leaks after several years.

[Sellick]

Thanks Colin, hadn't heard about yamabond or hondabond until just recently, if I have any issues with leaks, sounds like I'll look into replacing with one of those.

[mabeer]

I used metal no my m42 stroker build along with some Hylomar.  It's only been a little over a year but everything is still bone dry.

[autox320]

Just started reassembly of my engine and realized that I have two gaskets (one steel and one paper) that go between the timing chain case and the block... do I use both? I'm not seeing anything about two gaskets in the manual or online. RealOEM lists the steel gasket, but nothing about the paper. It seems strange to me to use both. If I'm supposed to pick one, is one better than the other?

I was about to post this exact same question. My first FULL M42 build, but when I disassembled the original motor with over 380,000 miles it had BOTH metal gasket on the block side, with a paper one on the timing case side. Two gaskets sandwiched between the lower case and block. So during assembly I typically use loctite518/permatex 51813/ yamabond for the entire engine except the head gasket and valve gasket. Well I took a gamble and decided to use the double gaskets with the victor reinz kit on the lower inner timing case to the block. Sprayed both with loctite 99ma just for insurance.

We'll guess what; near the head on the exhaust side I'd say about half the seam LEAKS with only 15mi on the engine. It's under pressure due to the pump also so keeps pushing out. For now I've gooped it with grey rtv along the seam, but plan to redo this. Problem is you have to remove the head again to tackle it.

In short I can see why they wanted to use the metal gasket on the block face side due to the oil maybe eroding it, but for the love of God just use loctite518/yamabond and forget gaskets. I've two other engines assembled entirely with permatex 51813 with no issues. One is my full S14 build and logged over 2000 track miles without a leak! I feel kinda dumb for giving the M42 gasket a shot on the lower cover. It was so large and intimidating with lots of surfaces, but I'll be permatex'ing it.

Sucks to take it back apart after a full build so going to keep breaking in the rings a bit longer then plan to pull it. Runs awesome!

Discuss further on this if your using a gasket here and or both gaskets. Long time no post for my user name, but this is our second daily driver car 1991 318i. I've a daily driver myself of a 1991 318is I posted about in this forum a few years ago.

Long live the M42.

[bmwman91]

To the best of my knowledge, the metal gasket is for the M44 timing case and paper is for the M42. This question came up on some 318ti forums, and it sounds like some of the holes in the gaskets also differ, and using the wrong one will starve the timing chain tensioner piston and sprayer.

I have an M44 timing case on my 2.1L M42, built by Metric Mechanic, and as far as I can tell it just has the metal gasket. I have not had the timing case off of this engine since it is practically new, but I did need to fix a leak in the oil filter housing and got a look at the timing case gasket where it sticks out at the edges and it is metal.

As an aside, I recommend switching to a later model M42 timing case because the deflector/idler sprocket in the E30 M42 is a time bomb. It WILL fail, either by blowing out its bearings, or by breaking off the boss on the timing case itself. Later M42's used a plastic guide rail there, which is vastly more reliable. You can also use an M44 timing case, which has the benefit of a larger oil pump (to move more oil), but you will need an adapter bracket to hold the crank position sensor since it is not part of the M44 timing case casting.

[autox320]

To the best of my knowledge, the metal gasket is for the M44 timing case and paper is for the M42. This question came up on some 318ti forums, and it sounds like some of the holes in the gaskets also differ, and using the wrong one will starve the timing chain tensioner piston and sprayer.

I have an M44 timing case on my 2.1L M42, built by Metric Mechanic, and as far as I can tell it just has the metal gasket. I have not had the timing case off of this engine since it is practically new, but I did need to fix a leak in the oil filter housing and got a look at the timing case gasket where it sticks out at the edges and it is metal.

As an aside, I recommend switching to a later model M42 timing case because the deflector/idler sprocket in the E30 M42 is a time bomb. It WILL fail, either by blowing out its bearings, or by breaking off the boss on the timing case itself. Later M42's used a plastic guide rail there, which is vastly more reliable. You can also use an M44 timing case, which has the benefit of a larger oil pump (to move more oil), but you will need an adapter bracket to hold the crank position sensor since it is not part of the M44 timing case casting.

First Thanks for the notes. All interesting points and this is the info that's nice to know about this motor.

I've seen earlier posts about the timing deflector wheel breaking off the casing. I've never seen that failure before. Like I mention in another thread our 318i build the motor had originally 380,000+ miles(odo quit several times) and deflector wheel wasn't the failure. It had very worn timing components and more likely jumped a tooth of chain or more. On dis-assembly noticed the lower guide had the bolt head ground off by the chain which is way too much chain slack. That is the area when the tensioner is out the chain can touch the bolt and washer holding the lower rail. So not only is it the gears that wear down, but the chain eventually stretches beyond what the tensioner can handle.
 
My daily is the same M42 91 318is with deflector wheel setup. It has over 250,000 miles on it so far with great compression. Head has been refurbished since the head gasket was sweating and profile gasket needed replacing again. Recently the timing chain was scraping inside at death rattle rpm range. Went in and replaced all the gears, chain, and guides. Sure it's about $700 in raw parts but most cars have belt replacement jobs that expensive. I believe this is required by at least 200k miles on a BMW engine regardless. The engine runs like new. 

I'll be pulling the lower inside timing case off on the fresh built 318i engine and may get a few pics. I don't think the metal gasket blocks the deflector wheel oil channel/jet path. But I'll look in a few days when it comes apart. Not sure yet if I just want to permatex the cover or 99MA spray a new paper gasket for it.

[autox320]

Ok just wanted to report back. @bmwman91; To be blunt your absolutely correct. The paper is for the M42 only. Do NOT use the metal gasket on an M42.


The metal gasket has a different path traced into it where the oil passage is to the M42 jet that feeds the idler pulley with oil. If use both like I did the metal one has trace paths that cross the paper path and causes a leak under pressure. The gasket then goes to the exhaust side where I saw the most oil under pressure leaking out the side.

So started late today and tackled this. The motor is very fresh built with all new Fastenal 10.9/12.9 hardware so simple wrenching to take back down to fix it.

I'll try to attach a string of pics of the paper and metal gaskets. The jet way path that leads to the idler pulley is recessed in the cover. So the entire surfaces can be permatexed but I opt'd for just spraying the paper version with MA99 (my fav).

[autox320]

Few more.

[bmwman91]

Great pictures. Those should serve as a nice reference for when the gasket question comes up again in the future.

Regarding the earlier discussion of the deflector sprocket, it must be one of those things that will either last a million miles for some people, and fail horribly for many others. A number of guys on here have had the timing case break, myself included, which is why I have been telling everyone to get the E36 M42 timing case if they are taking theirs off. Used ones are so cheap that is is just an incremental cost within the overall cost of a timing overhaul on the M42. Anyway, hopefully your good luck will keep up!

[varg]

Makes me wish I had been able to find an idler-free timing case to put on my M42 when I had it apart.

[1998ccc]

FYI from the Penske Parts ETK:

03    11141734422    GASKET ASBESTOS FREE (to 09/93)   0.12    1     $15.44
03    11141743032    GASKET STEEL (from 09/93)   0.12    1     $7.77

M44 show the same part # as the late M42.  Looks like the gasket changed when they redesigned the lower timing case from a sprocket to rail.

[bmwman91]

Good info. So it looks like you have to be mindful of which gasket you use when you use the later M42 timing case.

[autox320]

More confusion was real OEM lists the 4422 as ended; yet that's the paper one to use on an M42 that I ordered from worldpac and installed in the pic.