[JonTheGreek]

I'm at 100K miles and was going to replace the valve cover gasket. There is no indication of a leak I just want to do it as a preventative measure. From my understanding these valve covers get brittle over time.

My question is this, should I replace it both the gasket and valve cover, just the gasket, or leave it until it leaks?

[frchdragon]

BMW tells you to change both.
I changed my leaking gasket only.

I wouldn't do the job as preventive, but if you have time to do it, why not.
The waterpump replacement should be preventive.
Did you do your OFHG already? Planning to do it as preventive?

[McGyv3r]

I wouldn't change it unless its leaking since it's an annoying/time consuming job.

As I understand it, most places change the plastic valve cover since it can warp with age (heat cycles). Reusing a warped valve cover is likely to cause premature leaks, so shops recommend replacing the valve cover.

I would rather just replace the $50 gasket every 20-40k miles instead of paying for a $700 valve cover to hopefully get 100k miles out of it.

[thejeremyman9]

I would also say don't do the VCG as preventative... I would wait until the VC leaks, then since you are over 100k, strongly consider doing the VC as well.

[5w20]

Originally Posted by JonTheGreek

I'm at 100K miles and was going to replace the valve cover gasket. There is no indication of a leak I just want to do it as a preventative measure. From my understanding these valve covers get brittle over time.

My question is this, should I replace it both the gasket and valve cover, just the gasket, or leave it until it leaks?

I would wait for it to at minimum to start seeping, if it's already leaking you should already have plans to replace it.

[F32Fleet]

Originally Posted by JonTheGreek

I'm at 100K miles and was going to replace the valve cover gasket. There is no indication of a leak I just want to do it as a preventative measure. From my understanding these valve covers get brittle over time.

My question is this, should I replace it both the gasket and valve cover, just the gasket, or leave it until it leaks?

Both when it starts leaking.

[jgoens]

As others said, don't change it unless your bored, want to spend money and learn about the car. I changed my whole cover 2 months ago but it was leaking for probably a year...not an issue that really warrants immediate attention. That being said--I decided to do the whole cover because there is a filter inside that can fail and then you have to do the job again and there is a possibility of the cover being warped or having cracks so at least I know I'm all good with that.

[JonTheGreek]

Originally Posted by frchdragon

BMW tells you to change both.
I changed my leaking gasket only.

I wouldn't do the job as preventive, but if you have time to do it, why not.
The waterpump replacement should be preventive.
Did you do your OFHG already? Planning to do it as preventive?

I have not changed the OFHG. I have read that some of the rubber can get into the oil and maybe cause issues down the line?... Is this correct? As for the water pump I have thought about changing them out because I really don't want to be stuck somewhere because of something trivial as that.

I have no idea if any of these components have been changed at all.

I frequently detail the engine bay, about 1once a month or so, so I should be able to pick up on any leaks fairly quick.

[JonTheGreek]

Originally Posted by McGyv3r

I wouldn't change it unless its leaking since it's an annoying/time consuming job.

As I understand it, most places change the plastic valve cover since it can warp with age (heat cycles). Reusing a warped valve cover is likely to cause premature leaks, so shops recommend replacing the valve cover.

I would rather just replace the $50 gasket every 20-40k miles instead of paying for a $700 valve cover to hopefully get 100k miles out of it.

Could the warping be caused by not unbolting the valve cover correctly or overheating the engine from a failed water pump? Even without these variables, do they still warp?

[JonTheGreek]

Originally Posted by thejeremyman9

I would also say don't do the VCG as preventative... I would wait until the VC leaks, then since you are over 100k, strongly consider doing the VC as well.

Affirmative, thank you

[JonTheGreek]

Thank you everyone for your replies and recommendations. Very helpful in making my final decision, which is to let the sleeping dog lie.

[McGyv3r]

Originally Posted by JonTheGreek

Could the warping be caused by not unbolting the valve cover correctly or overheating the engine from a failed water pump? Even without these variables, do they still warp?

I doubt it could be warped from pulling the bolts out in a random order. I suppose it could get warped from overheating your engine, but it would have to get really hot, which likely means you've warped the head and/or blown the head gasket.

I think the valve cover warp is just from heat cycles over many years.

I don't think this applies to the n55, but when I replace an m20/m30/m50/m54/etc valve cover gasket, I put a dab of adhesive (like Drei Bond 1209) on any gaps (timing chain cover to head or m20 rocker shaft plugs) or sharp turns in the gasket (half moons).

[JonTheGreek]

Originally Posted by McGyv3r

I put a dab of adhesive (like Drei Bond 1209) on any gaps

Interesting, I will keep this in mind. Thank you.

[Revoltos]

Remember though, the valve cover also contains the positive crankcase ventilation valve. These valves do fail and will cause heavy breathing amongst other running issues. At 100k I would be looking at changing the valve cover with the inbulit pcv valve as a serious piece of preventative maintenance.

[LA1Z24]

The VCG bills something silly like 5 or 6 hours. It can be done in 1 hour in a home setting.

[JonTheGreek]

I am assuming that if I do replace I should just suck-it-up and get the BMW one, yes?...

[frchdragon]

Originally Posted by LA1Z24

The VCG bills something silly like 5 or 6 hours. It can be done in 1 hour in a home setting.

1 Hour on an N55 engine???
I would do it in 1 hour on other engine but not the N55. Way too many pieces to remove.

[jgoens]

Originally Posted by LA1Z24

The VCG bills something silly like 5 or 6 hours. It can be done in 1 hour in a home setting.

No way it can be done in 1 hour..not even close. I'm not a slow worker but did take my time....can't see the most skilled person who has done this job many times being able to do it in in less than 2 hours.

Originally Posted by JonTheGreek

I am assuming that if I do replace I should just suck-it-up and get the BMW one, yes?...

Yeah, for how much time it takes and the risk of screwing something up, it's not worth trying to save a couple hundred bucks.

[123Britt]

1 Hour --- Took me 2 days on my N54
.

So if we all (most) agree to Change the VC and not just the Gasket -- what Brand -- OEM or Aftermarket??
.
My current BMW VC was made by Mahle .
.

[n55david]

Originally Posted by 123Britt

1 Hour --- Took me 2 days on my N54
.

So if we all (most) agree to Change the VC and not just the Gasket -- what Brand -- OEM or Aftermarket??
.
My current BMW VC was made by Mahle .
.

oem cover for sure

[LA1Z24]

Well IDK what you guys are doing wrong. Again, it is an extremely easy cover to take off. 1 hour, that's it. 2 triangle aprons, the v support, the coils, coil grounds, and the valvetronic connector. Cover comes straight up. No wiggling, no finagling. The N52 VCG is a major PITA having to deal with the valvetronic motor.

[F32Fleet]

Originally Posted by LA1Z24

Well IDK what you guys are doing wrong. Again, it is an extremely easy cover to take off. 1 hour, that's it. 2 triangle aprons, the v support, the coils, coil grounds, and the valvetronic connector. Cover comes straight up. No wiggling, no finagling. The N52 VCG is a major PITA having to deal with the valvetronic motor.

I think there's a justified fear over breaking connectors and such while removing the VC.