BMW E36 Valve Cover Gasket Replacement Guide (M50/M52/S50/S52)

Difficulty: Intermediate | Time: 2 to 3 hours | Applies to: BMW E36 (1992-1999) with the M50, M52, S50, or S52 inline-six

If you can smell burning oil after a drive, see oil pooling around the spark plug tubes, or you've got oil weeping down the back of the block, your valve cover gasket is done. On an M50 or M52 it's not a question of if, it's when. The rubber goes hard, the seal lets go, and oil ends up everywhere it shouldn't be, including down into the spark plug wells where it cooks on the coils.

This is one of the most satisfying jobs you can do on an E36. Cheap parts, basic hand tools, and a leak that actually goes away. Let's do it right.

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Before You Start

BMW calls this the cylinder head cover. Enthusiasts call it the valve cover. Same part, same job. On the M50, M52, S50, and S52 it's a one-piece cover held down by a row of small cap nuts, each sitting in a rubber grommet that isolates the cover from the head. The factory manual is clear on the torque, we'll get to it, but vague on the tightening order, so we'll fill that gap with the factory M50 procedure.

Work on a cold engine. The plastic and the gasket are easier to handle and you won't burn a knuckle on the exhaust side. Have a clean rag handy because there's always a little oil left in the cover.

One scope note before you buy parts. The E36 sixes are the pre-VANOS-update M50TU and M52, so this is the earlier single-VANOS cover. The earliest non-VANOS M50 (through 1992, which includes some early 325i cars) uses a slightly earlier gasket, and the later M52TU and M54 (E46, late E39) use a different 15-bolt cover entirely. Buy by your engine and build, not by the "M52" name alone, or you'll end up with the wrong kit. More on that below.

What You're Replacing

The classic oil-in-the-plug-wells leak is fixed by two things working together: the fresh gasket set, which seals both the cover perimeter and the spark-plug tubes, and a new set of rubber grommets under the cover bolts. The grommets harden with age and are the number one reason a "new gasket" leak comes right back. Buy them separately, because the boxed gasket set does not include them.

Here's the part that trips people up. On the M50, M52, S50, and S52 there is no separate half-moon seal to buy. The rounded ends that seal the half-moon cutouts at the back of the head are part of the one-piece perimeter gasket. You seal those corners with a dab of Drei Bond 1209, not a rubber part. If a parts list is trying to sell you standalone half-moon seals for this engine, that's the older M20 or M30 design, not yours.

The set also carries the spark-plug-tube seals, the round seals that sit in the cover's tube openings and actually stop oil getting into the plug wells. Depending on the brand, they come molded into the perimeter gasket or as separate rings, but either way they're in the set. Fit them fresh.

Part	Part Number	Notes
Gasket set, M50 / S50 (325i, Euro M3)	11 12 0 034 107	One-piece perimeter gasket plus spark-plug-tube seals. Does NOT include grommets or washers
Gasket set, M52 / S52 (323i, 328i, US M3)	11 12 0 034 108	Same contents as above, different profile. Not interchangeable with the M50 set
Bolt grommets (about 15)	11 12 1 437 395	Sold individually, not in the set. The real anti-leak item. Replace all of them
Half-moon corner sealant	Drei Bond 1209 (07 58 9 062 376)	High-temp sealant, a dab at the corners only. See the note on availability below

The sealant is worth a word. Drei Bond 1209 (also sold as Three Bond 1209) is the factory-specified product, PN 07 58 9 062 376. BMW has marked that 30 ml tube as discontinued and it supersedes to 83 19 0 404 517, so check live stock. Any high-temp RTV rated for the job works as the common substitute, and it takes almost nothing, so one small tube lasts many jobs.

What You'll Need

Tool	For
10mm socket and nut driver	The cover cap nuts and the coil bolts
8mm socket	The coil ground-strap nuts
Torque wrench, in-lb capable	The cover nuts are only 10 Nm. A foot-pound wrench is too coarse here
Drei Bond 1209 or equivalent high-temp RTV	Half-moon corners only, per the manual
Plastic scraper, brake clean, rags	Cleaning the sealing surfaces without scratching the alloy

Optional but smart: a fresh set of spark plugs. The coils are already out, so it's the perfect time.

Fitment Notes

The two engine families take different gasket sets and the covers have different profiles, so match the set to your engine (11 12 0 034 107 for the M50/S50, 11 12 0 034 108 for the M52/S52). We're not going to make a metal-versus-plastic cover claim here, because real E36 sixes came with cast covers and the plastic covers people talk about are the later M52TU and M54 generation, which isn't your car.

Two things differ between the M50 and M52 that matter on the bench. The M52 and US S52 have a secondary-air check valve at the front that has to come off first. And the breather setup differs, PCV on the M50 versus a CCV on the M52, so pay attention to which hose goes where when you pull them.

Step 1: Clear the Top of the Engine

Disconnect the negative battery cable (on the E36 the battery is in the trunk). Pull the plastic engine covers off the top.

Now deal with the coils and their grounds. Several ground straps for the ignition coils land on the cover studs and on the coils themselves, usually an 8mm nut on the studded inner cover nuts. Take a photo of exactly where every strap sits before you touch anything, because putting one back in the wrong spot throws misfire codes. Those studs like to spin, so hold each one with a slim wrench while you back the nut off. Unclip the coil harness, pull the coils, and set them aside in order.

If you have an M52 or a US-spec S52, the factory routine removes the secondary-air check valve at the front first. If yours has one and it's blocking the front fasteners, take it off now.

Step 2: Remove the Cover

Open the wiring harness channel and move the wires aside. Disconnect the breather/CCV hose from the cover.

Unscrew the 15 cap nuts. Lift each nut, its washer, and its rubber grommet out as you go and keep them in order. Two of them hide under the spark-plug cable duct at the rear, so you have to detach that harness duct to reach them. Most take a deep 10mm socket, but the rear fastener by the fuel rail needs a shallow socket for clearance.

With the nuts out, the cover is still glued down by the old gasket. Tap it gently sideways with a rubber or dead-blow mallet, working from the front toward the rear, to break the bond, then lift it straight up. Never use a metal pry bar against the head, you'll gouge the alloy sealing surface.

Step 3: Clean the Sealing Surfaces

Scrape all the old gasket material off both the head and the cover. Take your time, get it spotless, and don't drop debris down into the head. Wipe the sealing land clean and dry with brake clean so the new gasket has a clean surface to seat against.

While you're here, check the cover for warping across the sealing flange. A warped cover leaks even with a perfect new gasket, and on high-mileage cars it does happen.

Step 4: Fit the New Gasket, Tube Seals, and Sealant

Seat the new perimeter gasket into the groove in the cover, dry. No RTV on the gasket itself. Press it fully home all the way around and confirm the spark-plug-tube seals are seated in their bores, these are what stop oil getting into the plug wells. Check that the half-moon ends sit correctly at the rear.

Now the only sealant on the whole job: put a small dab of Drei Bond 1209 at the four corner junctions where the gasket transitions, the two rear half-moon cutout corners and the two front corners at the VANOS/timing-cover joint. A thin film at those corners, nowhere else. You are not laying a bead around the perimeter. If you substitute a generic RTV, use an oxygen-sensor-safe high-temp one. Ordinary construction RTV outgasses as it cures and can poison an O2 sensor.

Before it goes back on, look at the bolt hardware. Each cap nut rides on a rubber grommet and a washer. This is the real fix for the leak. Put a fresh grommet on every bolt location.

Step 5: Reinstall and Torque in Sequence

Set the cover down square, keeping the half-moons and the gasket seated as it lands. A telescoping mirror lets you confirm the rear half-moon ends are still seated once the cover is down, and get it on before the sealant skins over. Drop a fresh grommet and washer onto each fastener. BMW says replace those washers every time, not just the grommets.

Start every fastener by hand with no preload, get them all threaded finger-tight first. Then bring them up crosswise, working from the center of the cover out toward the ends in stages. Final torque on the M6 cap nuts is a light 10 Nm (89 in-lb). The few larger M7 bolts where the cover meets the timing-chain cover take 15 Nm (11 ft-lb).

Fastener	Torque
Cover cap nuts to head (M6)	10 Nm (89 in-lb)
Cover to timing-chain cover (M7)	15 Nm (11 ft-lb)
Spark plug to head	23 to 25 Nm (17 to 18 ft-lb)

Torque values from the factory manual. The spark plug spec shows as 25 Nm in the maintenance chapter and 23 Nm in the cylinder head chapter, either is within tolerance, so we give the range. Plugs are included because the coils are already out and it's the natural time to do them.

Step 6: Reassemble and Leak-Check

Reconnect the breather/CCV line, refit the coils, and return every ground strap to the exact stud it came off. Plug the coil harness back in, refit the secondary-air check valve if you removed it, reinstall the plastic covers, and reconnect the battery last.

Start the engine and let it idle. Check the cover perimeter, the half-moon corners at the back, and the plug wells for any weeping. A clean, dry cover after a few heat cycles means you're done.

Troubleshooting

It still leaks after the job. Nine times out of ten it's a half-moon corner that didn't get sealed, or a grommet that was reused and never seated. Pull the cover, check the corners, and replace any grommet you tried to save.

The cover won't pull the gap closed evenly. Something's binding underneath, usually a harness or a hose caught under the lip. Don't crank the bolts to force it flat. Lift it, find the snag, reseat, and start the fasteners over.

A misfire code after the job. A ground strap is on the wrong stud or a coil connector isn't fully clicked home. Recheck the coil harness and every head ground before you blame the plugs.

Oil back in the spark plug wells. Either the gasket set didn't include fresh tube seals and the old ones are hard, or the cover itself is worn or warped at the tube openings. Verify your set had the tube seals, and check the cover flatness.

A Note on Doing It Once

The valve cover gasket is a wear item on these engines, and 25-year-old rubber simply doesn't seal anymore. The trick to doing it once is the parts people skip: the fresh grommets and the sealed half-moon corners, not just the perimeter gasket. Do the whole job, replace every grommet, seal the four corners with a dab of 1209, and torque to spec, and this leak is gone for good.

Wrap-Up

Clean engine bay, no more burning-oil smell, and a job you can knock out on a Saturday morning. While you're in there, give the coils and plug tubes a look and check the breather hoses for cracks, since you've already got everything off. For the full set of E36 fastener specs, see our BMW E36 Torque Specifications guide. If your cooling system is also tired, our E36 Thermostat Replacement guide and Cooling System Flush guide pair nicely with this one.

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