Just replaced my oil cap...

[Singletrack]

After having the second OEM oil cap leak on me, I have now gone to the new design. I honestly don't know why BMW even sells/stocks the original design since it sucks and the new one fits. Totally bizarre to me. The new design is noticeably tighter on the valve cover.

Original from my 09/08 build MY2009 M3: 11127832157
New part I just got from getbmwparts.com: 11128507153

Hope that helps someone.

Later!

[THE TECH]

You have pics of them? My MY2012 leaks as well. Wonder how new this design is? I was thinking about getting another o-ring for it and doubling up to see if it helped.

[Z K]

I had mine replaced due to leaking and they used the same one as a replacement. I wonder what the difference is with the new one besides the appearance of the cap.

[THE TECH]

I just checked the part number and it appears I already have the new one.

[Singletrack]

Originally Posted by THE TECH

I just checked the part number and it appears I already have the new one.

Ha! Well, I'll let you know if mine leaks.

[dale.b]

A few days ago I was driving home and my 2008 M3 had a ridiculous leak from the oil cap. I am talking about the engine and exhaust smoking from the oil burning on the surfaces. At first I thought it was all the track driving I am doing had blown something. I was nervous as hell that I broke something serious.

I got home, popped the hood and there was oil everywhere in the engine bay. then I noticed oil all over the floor.

After cleaning it all up and washing the engine bay, I started the car up and noticed that there was oil seeping out the cap when the engine was revved.

I ended up buying the newer style cap, and that fixed it. However, after some spirited driving this weekend, I am noticing that even the newer cap has a very tiny amount of oil seeping out.

Does anyone know of a good aftermarket oil cap? Or of any methods to improve the seal with stock oil caps?

[Singletrack]

Wow - what a mess.

I too had some leaking with the new style : (

It *seems* that the key is to totally clean the oil cap, then apply a thin layer of oil to the cam cover, then screw down cap. Oil on both surfaces is too much; both dry also leaks. Still testing it out though...

[THE TECH]

Originally Posted by Singletrack

Wow - what a mess.

I too had some leaking with the new style : (

It *seems* that the key is to totally clean the oil cap, then apply a thin layer of oil to the cam cover, then screw down cap. Oil on both surfaces is too much; both dry also leaks. Still testing it out though...

I was thinking about finding out of we can just get the o-ring that's on the cap and maybe double them up for a better seal.

[surlynkid]

Originally Posted by THE TECH

I was thinking about finding out of we can just get the o-ring that's on the cap and maybe double them up for a better seal.

do not double up the o-ring. it will really leak then. you can easily remove the o-ring, measure it, and then buy one that is thicker. that can be tricky though as what i think you want is more depth while maintaining ID and OD to fit. whatever you buy, make sure it is of the right material and durometer to withstand the duty. sounds like you want a custom fit gasket which any o-ring and gasket shop can make. just give them the dimensions and material specs.

[Z K]

Originally Posted by surlynkid

do not double up the o-ring. it will really leak then. you can easily remove the o-ring, measure it, and then buy one that is thicker. that can be tricky though as what i think you want is more depth while maintaining ID and OD to fit. whatever you buy, make sure it is of the right material and durometer to withstand the duty. sounds like you want a custom fit gasket which any o-ring and gasket shop can make. just give them the dimensions and material specs.

Unfortunately, depending on where you live, a "o-ring and gasket shop" is kinda hard to come by.

If someone could source these, I think it's something a lot of us would want.

[THE TECH]

Originally Posted by surlynkid

do not double up the o-ring. it will really leak then. you can easily remove the o-ring, measure it, and then buy one that is thicker. that can be tricky though as what i think you want is more depth while maintaining ID and OD to fit. whatever you buy, make sure it is of the right material and durometer to withstand the duty. sounds like you want a custom fit gasket which any o-ring and gasket shop can make. just give them the dimensions and material specs.

Not sure why you think it would leak more. With twice the thickness, it should seal much better assuming that the reason it's leaking in the first place is due to lack of a seal.

[surlynkid]

Originally Posted by Z K

Unfortunately, depending on where you live, a "o-ring and gasket shop" is kinda hard to come by.

If someone could source these, I think it's something a lot of us would want.

Yes, I live where these are commonplace in the heart of chemical plant and refinery land. I work in one, so I have access to all of these types of things.

[surlynkid]

Originally Posted by THE TECH

Not sure why you think it would leak more. With twice the thickness, it should seal much better assuming that the reason it's leaking in the first place is due to lack of a seal.

Twice the thickness is no problem. Using double stacked o-rings to do it is the problem. My background is BSChE with 23+ years in chemical plants. It will fail. You need a custom sized one that can withstand the heat and the oil. A nice custom made Kalrez one would be the ticket.

[THE TECH]

Originally Posted by surlynkid

Twice the thickness is no problem. Using double stacked o-rings to do it is the problem. My background is BSChE with 23+ years in chemical plants. It will fail. You need a custom sized one that can withstand the heat and the oil. A nice custom made Kalrez one would be the ticket.

I know I used the term o-ring which by definition would cause an issue if you tried using two actual o-rings stacked. Of course the oil cap uses a gasket and not technically an o-ring as I stated. That being said, stacking two gaskets should be no issue.

[surlynkid]

Originally Posted by THE TECH

I know I used the term o-ring which by definition would cause an issue if you tried using two actual o-rings stacked. Of course the oil cap uses a gasket and not technically an o-ring as I stated. That being said, stacking two gaskets should be no issue.

stacking two gaskets is a problem. buy one gasket that is twice as thick.

[dale.b]

Maybe surlynkid could come up with a replacement gasket for us?

[THE TECH]

Originally Posted by surlynkid

stacking two gaskets is a problem. buy one gasket that is twice as thick.

I don't agree. We're not talking about something that's ultrasensitive to sealing.

[m3an]

Originally Posted by THE TECH

I don't agree. We're not talking about something that's ultrasensitive to sealing.

good luck but the other guy is right. Ever see an oil filter with two gaskets on it. . It leaks like a civ. They do make some A/M caps, but they're hard to find. I just replaced mine as well, shitty design but the dealer but the old model on as well and I see the new one as being a better looking design at least.

[THE TECH]

Originally Posted by talontid

good luck but the other guy is right. Ever see an oil filter with two gaskets on it. . It leaks like a civ. They do make some A/M caps, but they're hard to find. I just replaced mine as well, shitty design but the dealer but the old model on as well and I see the new one as being a better looking design at least.

I completely understand what the other guy is saying. Being what it is though, I don't see it being much of an issue. Yes, I could definitely be wrong since I haven't tried it. Comparing this to an oil filter though is not apples to apples. The same pressures on a filter are not present at the oil cap.

[dale.b]

The new cap is starting to leak too. I think I am going to try doubling up the gaskets and see what happens.

[surlynkid]

Originally Posted by dale.b

Maybe surlynkid could come up with a replacement gasket for us?

Give me the exact dimensions of what you want.

[dale.b]

Originally Posted by surlynkid

Give me the exact dimensions of what you want.

48mm id x 62mm od x 2.3mm depth is the stock gasket.

I am thinking 4mm depth might be good.

The other thing that might be an issue is that the oil cap has a lip to keep the gasket captive. I am thinking that the lip won't stop a bigger gasket from fitting.

Also, if you use two gaskets, and put a layer of liquid gasket in the middle of them, it may seal pretty well, and it would also allow for the lip to grab the bottom gasket and still kjep it captive. I only wonder if two gaskets are too thick??