[Biginboca]

Just wanted to share some lessons I learned installing a Crank Seal Guard on my 2009 N52 328i E92. Some people feel these are pointless but I decided they are cheap insurance, and frankly I also don’t mind tinkering so I decided to run one. Little did I know how much tinkering I was in for

Part 1:

I ordered and Installed the ECS crank pulley guard.



Do not order this piece of crap product! For some reason ECS included stainless bolts but the oem uses aluminum in the location for the N52 block because of the galvanic reactivity of magnesium with other metals. Magnesium and Stainless are totally incompatible. Also Magnesium and Titanium are not compatible either so don’t think you will be smart there and go for titanium lol

So I knew I had to order aluminum M8 x 40mm Cap Head aluminum bolts from Pro Bolt for the install but it ended up that this is only the least of the concerns with it.

Right after install my car wouldn’t start. I did all the checks of battery, etc and came back to it being the starter failed.

Strange coincidence that a starter would fail right after another install right? Well it turns out it wasn’t a coincidence!

I ordered a new starter next day air. Installed it and car right up with a very strong crank… But immediately I noticed the throttle felt a little unresponsive. Look under hood see smoke. Shut down and look closer the smoke smells like crap never smelled this before.

So I pull the crank the crank pulley back off and… low and behold the bottom of the stupid ECS guard is rubbing the inside of crank pulley/balancer:





So I took that garbage off and emailed ECS asking for a refund, which they approved and back it went. Meanwhile looking at the product reviews I saw this:



So it’s marketed by ECS for all N5X 6 cyl engines but we can see now that doesn’t fit at least 2 of them (N52 and N55).

And I’m guessing because my starter was near end of life the added drag of the Guard rubbing on the Crank Pulley/Balancer killed my old starter too.

Part 2:

Next up I tried the Malo Industries crank guard as recommended by CalvinNismo

This guard itself has no issues but again we are dealing with fastener problems. Malo includes 2 M8 x 40mm stainless button head screws which are obviously not compatible with the Magnesium N52 Block metallurgically.



So once again we are back to hunting for aluminum fasteners. Luckily I already had a few on hand ordered in preparation. I had some black aluminum Cap Head Bolts ordered from pro bolt M8 x 40, I had some bolts suggested to me BMW p/n 07129904795 which turned out to be steel (Not Aluminum!!!) but also M8 x 40, and then the bolts I would recommend which are BMW P/N 11137582340 which are M8 x 50mm Aluminum.

Although I recommend bmw p/n 11137582340 M8 x 50 Aluminum they are going to be too long as they come (the stock bolts in this location are about 37mm and the Malo guard has like a 5mm thickness it adds with its mounting flanges.). So ideally you will have a 42-43mm length bolt to use. Another issue is the tall head or wide flange on many bolt heads will hit the N52 crank harmonic balancer. Have a look:



In this pic above the Pro Bolt M8 Cap head M8 x 40 is on the left (black) and the bolt I used the BMW P/N 11137582340 M8 x 50 is on the right. Both have clearance issues with the harmonic balancer/crank pulley.

So I had to turn down the flange on the bolts to a smaller diameter and they just fit. I put the threaded portion into a cordless drill and then spun the head flange on the bolt on my belt sander until the OD was flush with the flange of the Malo guard. This gave about 1mm of clearance. Here’s one bolt I finished and the second one before I started:



And here’s how it looked after clearancing:



Then I used a dremel with a cut off wheel to shorten the bolt about 8mm so the total length under the head (the entire remaining threaded portion under the head flange) was 42mm long. After cutting I cleaned the cut threads up with some scotch bright abrasive pad and everything installed perfectly without issues!



So the Malo Guard is great, but the bolts are not if you have a Magnesium Block N52 motor, and in that case you will need to figure something out with the fasteners which I recommend the BMW aluminum bolt p/n 11137582340 M8 x 50mm Aluminum and modifying it as described.

As of now the Malo Industries guard has been on for a week without any issues.

[Soden82]

Holy crap, what a can of worms you opened. We are very appreciative of your feedback and knowledge about these two crank seal plates!

[E92_William]

You'd think someone making a product from scratch would take in count all of this before bringing it to market, as just trying to install it would have shown all these issues.. You shouldn't need to mess with trimming bmw oem bolts just to make the part fit. Nice work

[rjahl]

Originally Posted by E92_William

You'd think someone making a product from scratch would take in count all of this before bringing it to market, as just trying to install it would have shown all these issues.. You shouldn't need to mess with trimming bmw oem bolts just to make the part fit. Nice work

I really wonder how much abuse one of these belts can take before they fail?

I replaced the belt on my E85 at 150,000 miles and it looked new. Current car is 10 years old and the belt is perfect. I'll change it next year for good measure but seriously how many belts fail on maintained motors? Would it be better to simple install a new belt every decade or so?

I understand one one BMW model has an issue with clearance when the motor mounts get old. But that's probably the same thing, replace the mounts.

Just my thoughts…….

[E92_William]

Originally Posted by rjahl

I really wonder how much abuse one of these belts can take before they fail?

I replaced the belt on my E85 at 150,000 miles and it looked new. Current car is 10 years old and the belt is perfect. I'll change it next year for good measure but seriously how many belts fail on maintained motors? Would it be better to simple install a new belt every decade or so?

I understand one one BMW model has an issue with clearance when the motor mounts get old. But that's probably the same thing, replace the mounts.

Just my thoughts…….

I think they can go for ages as long as little to no oil gets on them tbh since the tensioner has a lot of range to move if it stretches a bit. I have never changed the belt in my car and I bought it with 100k and I'm at 142k right now, pretty sure it hadn't been changed before. It looks good so far and has really only gotten coolant on it afaik.

I should probably swap it out for good measure and do the crank seal guard. Which honestly looks like I could build one myself out of aluminum sheetmetal at work lol

I had a belt go through the front main in my old 335i. But I didn't know anything about bmws before and I ignored the oil filter housing and cooler leak. It slipped and magical $2500 repair bill. That car was definitely completely neglected though

[Biginboca]

Originally Posted by rjahl

I really wonder how much abuse one of these belts can take before they fail?

I replaced the belt on my E85 at 150,000 miles and it looked new. Current car is 10 years old and the belt is perfect. I'll change it next year for good measure but seriously how many belts fail on maintained motors? Would it be better to simple install a new belt every decade or so?

I understand one one BMW model has an issue with clearance when the motor mounts get old. But that's probably the same thing, replace the mounts.

Just my thoughts…….

These are good and valid points to consider. Most likely a well maintained engine would never need one of these guards, and probably even many neglected ones wouldn’t.

For me, well my car is spoiled… CSL gets everything she wants and no maintenance is neglected

So investing $90 to prevent the one possible breakage which will be catastrophic to the N52 I felt was worthwhile. $90 is a lot cheaper than the $3k guys spend on rod bearings on N54/N55/S65 to prevent a catastrophic failure. (Yeah I went there )

And lord knows I’ve spent much more than $90 on pretty much every other mod I’ve done except my $20 DIY Ram intake

[Cloverdale]

With the Malo guard you will have no issues using either the bolt's Malo supplies or the original bolts bolts requiring removal in order to install the guard providing you use the loctite product provided by Malo.

[Biginboca]

Originally Posted by Cloverdale

With the Malo guard you will have no issues using either the bolt's Malo supplies or the original bolts bolts requiring removal in order to install the guard providing you use the loctite product provided by Malo.

The original bolts are aluminum torque to yield single use bolt, so not ideal to reuse them. These are marked with blue paint on their heads.

The Malo bolts are stainless so also not usable for N52.

Why are you saying otherwise?

[desertman123]

Very valuable research and a great resource, now we have somewhere to point when someone asks about these products!

Going off what rjahl said - my original belt looked basically new when I replaced it at ~8 years old/80k miles. Definitely just need to watch for oil leaks and I doubt there'll be issues.

[Cloverdale]

Originally Posted by Biginboca

The original bolts are aluminum torque to yield single use bolt, so not ideal to reuse them. These are marked with blue paint on their heads.

The Malo bolts are stainless so also not usable for N52.

Why are you saying otherwise?

Could you explain the metallurgical reason's why using a stainless bolt with loctite is not usable in this application?

[Biginboca]

Originally Posted by Cloverdale

Could you explain the metallurgical reason's why using a stainless bolt with loctite is not usable in this application?

You didn’t answer my question, you only asked me one. This feels like the elementary school playground when a kid says “I know you are but what am I?”

But I’ll play along and answer your question even though you don’t have the courtesy to answer mine. So I have to admit I’m not a metallurgist only a hobbyist and therefor I rely on what BMW gives us in their technical manuals and assume they do their homework. And then I can also sometimes learn something by Google too lol

This is an except from the bmw technical info on the N52:



What I have circled there reads:

“The aluminum bolts are needed to prevent contact corrosion. Conventional steel cannot be used in magnesium for any reason. The aluminum bolts can be identified by a blue colored bolt head and their light weight.”

Then when I Google I find there are many charts like this online and the basic premise is the further apart the materials are the more reactive they are together.

Aluminum and Magnesium are near the top while stainless is in the middle and titanium is near the bottom.

Mild Steel, Alloy Steel, and even Cast Iron are all actually closer to Magnesium than stainless is on this chart so any of those would actually be preferable to stainless even though none are acceptable according to BMW.

(And interestingly Titanium is third from the bottom so actually very reactive with Magnesium so would probably be the worst fasteners to use on n52 not that anyone asked.)



So how about you answer the question I asked and also why BMW would go to all the trouble to explain this to their Techs, and also why BMW would even bother to manufacture Alumimum bolts in the first place when they could have just said “use loc tite” with any old crap fastener in their manuals?

[Cloverdale]

In respect to the Malo product for purchaser's and the product itself you're creating an issue where an issue need not exist. Approaching 600 applications of the Malo guard and no issues.

[desertman123]

There IS an issue. No one wants their engine block to corrode from the inside.

I'd trust well-studied metallurgy and chemistry before some anecdotal evidence from a company looking to sell me something.

https://www.intechopen.com/chapters/62964

Galvanic corrosion is a common corrosion feature of Mg alloys. For example, galvanic corrosion may occur when Mg parts are connected or welded with the steels in lightweight powertrains and automotive bodies. In human body fluids, severe galvanic corrosion emerges when degradable Mg screws are connected with the bone plates made of titanium and stainless steel. This scenario is attributed to Mg that is located in the most active end in galvanic series of metals. Therefore, Mg and its alloys become the anode when connected to cathodic metals such as stainless steels and titanium alloys. This kind of galvanic corrosion is also termed bimetallic corrosion.

[Biginboca]

Originally Posted by Cloverdale

In respect to the Malo product for purchaser's and the product itself you're creating an issue where an issue need not exist. Approaching 600 applications of the Malo guard and no issues.

So it sounds like you work for Malo or else how would you know about the 600 applications. You never answered the questions and it seems like are defending a company which frankly was never attacked. I said the product was great just the fasteners are not suitable. Which as you can see BMW says also and I’m just repeating it from their technical info.

You are not doing Malo any favors with the attitude. A better attitude would be “oops we screwed up. We will fix it and use suitable fasteners going forward.”

The attitude of defending what isn’t right makes you look really bad in my opinion. I get the same from my teenage son so I’m used to it lol

[Cloverdale]

I'm not connected to Malo in any way other than being a satisfied customer. Some are placing way too much support behind BMW whom have known about the engine imploding serpentine belt issue for at least a decade and offered consumers nothing. A corrosion issue developing using stainless bolts in this application won't become an issue in our lifetimes. Still concerned, just reuse / snug the bolts BMW placed there using loctite, which Malo supplies.

[Malo_Industries]

Hey there,
you are absolutely right - galvanic corrosion will occur but the amount and severity of the corrosion is far from being problematic. The Anode (your engine block) is far larger than the Cathode (SS bolt) and the corrosion will occur very very slowly.
The corrosion you will get will looks like drywall dust and can be removed with a toothbrush and won't eat holes in your block.
"IF" your engine block was made of stainless steel and you'd use magnesium as a fastener then you would have a problem, but that is not the case here.

I did lots of research on this topic before choosing stainless steel as a fastener.

Please feel free to educate me if you believe I'm out for lunch. I'm always willing to improve my product.
I'm not very active on forums so please send me note via email:
info@maloindustries.com

Cheers,
Marcel

[Biginboca]

Originally Posted by Cloverdale

I'm not connected to Malo in any way other than being a satisfied customer. Some are placing way too much support behind BMW whom have known about the engine imploding serpentine belt issue for at least a decade and offered consumers nothing. A corrosion issue developing using stainless bolts in this application won't become an issue in our lifetimes. Still concerned, just reuse / snug the bolts BMW placed there using loctite, which Malo supplies.

My last comment to you.

The purpose of the guard is to prevent a very low risk failure for the N52. An *almost* impossibility. Anyone who cares enough to buy one of the guards is obviously very risk averse, hence the purchase. I am one of these people as it seems are you.

So to sell this “risk averse person” a product to protect their motor from a 1 in a 1,000,000 chance and then ask them to now accept the guaranteed risk of corrosion (SS bolts) or fatigued bolts failing (stock single use bolt) is just damned stupid. Sorry to be so blunt. It’s like selling water to a fish. Makes no sense.

Now for the record there are companies selling guards with aluminum bolts included. So they have likely done more homework or understand their target market better than Malo. When the stock bolts are aluminum and the manufacturer recommends only such, why choose to use anything else other than what must be ignorance of these facts. A simple mistake I assume because it would be very bold to say BMW doesn’t know their stuff and I know better with my SS fasteners.

The purpose of this thread was to show the Malo product is superior btw. I’m running it and like it, and have had no issues. I just had to swap the fasteners to comply with the BMW requirements for my N52 motor.

[Cloverdale]

The BMW engine damaging belt implosion issue occurs exponentially more frequently than you're describing, in fact is not uncommon. What is still unclear is what you may or may not know in respect to the damage to the ECS guard you installed as your experience is the only one I can find reference to / mention of. The crank balancer / pulley in these applications are also known to come apart / separate due to failure of the seal within. Marcel from Malo Ind. has spoken to (see above) your concerns re stainless bolt use in this application.

[rjahl]

Biginboca has the right attitude. He's provided constructive criticism while complimenting a product.

He also recognized that the need for this product is really non existent but he wanted it anyways. Piece of mind I guess.

I think anyone anal enough to affix this device will not tolerate using the wrong fasteners.

BMW has not seen Tsunami of broken belts and blown motors. They simply have millions of motors on the roads and not all of them receive the level of care they should be receiving. Modem belts don't immediately dissolve when they come contact with oil or coolant. It takes time for the damage to slowly occur. Anyone that bothers to check under the hood will probably catch the belt before it becomes a problem.

[CTinline-six]

Aren't the head bolts stainless steel?

I've installed two of the Malo guards on N52s.

[Malo_Industries]

Fair enough!
I will try to source aluminum bolts and add them as an option.

My wife just read my pervious post and said it sounds like I'm being passive aggressive and to stop writing like I'm writing in German. My apologies!

[jonwilli]

Originally Posted by Malo_Industries

Fair enough!
I will try to source aluminum bolts and add them as an option.

My wife just read my pervious post and said it sounds like I'm being passive aggressive and to stop writing like I'm writing in German. My apologies!

Hi any chance of a set the Alu bolts you will offer as an option? I currently have a Malo guard fitted to the N52 in my 130i which I am very happy with. I was planning on removing the Stainless Steel bolts with some 40mm Alu bolts but didn't realise until I read this thread there may be clearance issues with the harmonic balancer.