When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
An fyi to anyone planning on swapping to aftermarket mounts, specifically if using VRP mounts on a car like mine that has a horizontal top bolt; 2016 E550 Coupe 2WD.
I needed motor mounts since they're old and the torque test showed more movement than I'd like. So I order a set of VRP mounts that says fits my E550. The mounts arrive and they're wrong... On mine the lower two bolts thread into the motor mount from the bottom. The VRP just had holes, no threads, and the tapered part around the holes that fit into the frame is different. Next, these mounts are for vertical top bolts, my top bolt is horizontal. VRP sends me new base plates, I swap them out, send the old ones back. No cost to me, just the hassle, not a big deal. For the horizontal bolt issue they said I need to scavenge the vertical to horizontal adapter piece on the oem mounts. See the first pix showing the typical mount on left and horiz adapter on right. Uggg... Not ideal, but what could go wrong. Famous last words.
I pull the Left/Driver side mount first, and getting the mount out of the car and in hand was pretty easy, certainly easier than youtube vids I saw of similar cars. First mount in hand, I'll be able to knock out both sides before dark.
On the top of the horizontal adapter you can see what appears to be a cover with a chisel like peen mark on either side. I thought it was a cover for the nut, but it's the nut, which is square and slides into the adapter. The peen spots simply hold the nut from falling out. I made two little cuts with my Dremel to free it up, then it slides out. No biggie and doesn't even register as a problem compared what awaits.
Once the nut is out, I can see the oem bolt that connects this adapter to the motor mount. The bolt takes a 7mm Allen. Who the hell uses 7mm? It's a first for me, and I don't have one, so I made one by grinding down a 5/16" Allen. This is for the better since Allens are loose fitting and easily round out the bolt if you apply any torque, so a tight fitting one is ideal. It wasn't enough. I lubed it, then before pushing my luck I heated it, pounded on it etc and only succeeded in rounding it anyway. So I modified a T50 with a 3/8" drive, or maybe it was a T55, to be a pound-in fit to the hole. An Easy-Out of sorts, and it still just tore up the bolt. This pretty much narrows it down to drilling it out. I remembered the VRP mounts came with bolts, so no biggie, and I drilled it out. Once I have the adapter off I grab the VRP mount and see the VRP bolts are not the same... The VRP bolts are tapered, like a flat head wood screw. Plus the head OD is too big. Fk... Wth are these screws for, considering all the youtube vids I see show the vertical style using a hex bolt. So if it's not a hex for a vert mount, and obviously doesn't fit mine, what does it fit?
So I modified the VRP bolt as you can see in the pix. Not ideal, but should be ok. Then I discover the recess in the motor mount is deeper than the adapter reaches, so the center of the adapter won't be bolted metal to metal like it needs to be. Instead it's only making contact on the thin outer edge and basically the bolt torque and engine weight will be trying to break it. Specifically the bolt torque... Any fears of using the tapered bolt are now greatly amplified.
I'm not sure what the air gap is between the two but at least .5mm and I have no washers or shim stock on hand to fill it. Or I could grind off the outer edge of the adapter which I probably should have done but I was so sick of the BS at this point that I just bolted it on as-is since I no longer want the mounts and at this point they're just temporary until I can get different ones. Obviously I will not be installing the other mount.
I used minimal torque on the VRP bolt to reduce risk of breaking the adapter, probably less than 10 ftlbs, and soft Loctite so it won't work it's way out. Now I also fear that if that adapter cracks and lets go, I'll be buying a new hood as well.
This is lot of lost personal time, and I guess I'll have to wait and see if VRP says it's also a lost $500. At the very least, maybe some others will learn from my mistake.
But wait, there's more!
I fire it up and first thing I think; WTF? Vibration city! My steering wheel must have been resonating just right because it felt like I was holding a vibrator! I also checked the side of my pass seat headrest, which is always a go-to test for vibes, and it's bad. It does get a lot better at higher revs but still ridiculous. Not only unacceptable for me, but I can't possible give anyone a ride in this thing...
We're not done, there's more: I notice Red on my HP Tuners Scanner I use to log data. Red means bad and in this case it's retarding spark timing, a lot! Keep in mind I'm still in Park and my rev limiter is set at 2K, so I can't lean on it, I'm just gently revving as high as 1900 and back to see how it's vibrating. Not only is it retarding spark, it's doing it at levels I've never seen before and on all cyls! Nothing like this has ever happened under any condition, ever, and I'm only idling!
Before this I'd occasionally get .75 to 3 deg retard on one cyl, for a second or so at full throttle. In rare cases two cyls. This is actively retarding non-stop, all cyls, up to 9 degrees. I can only assume the normal eng sounds are being amplified or resonating somehow, like the steering wheel. Also remember I only have one VRP mount in, the Right/Pass side is still oem. I can't imagine having both in.
For those who don't know, retard not only costs you that lost timing, but engines like mine will pull boost as well, and they'll do it at a fraction of the timing this is pulling.
When I replaced the base plates I could see the inside and feel the urethane in them. I thought; that's awfully stiff, but there are people on youtube and forums saying they can barely tell the difference. I don't recall if they were talking about VRP or not, just that everyone seemed fine with aftermarket. So I assumed the engine is pretty smooth and the soft-ish car and insulation absorb as well and it's good.
Another thought, which I'm only having just now, is maybe the body of the mount is hitting the bracket that connects to the engine. I've ran solid mounts before and it's the only thing that compares to the vibration I felt today. I didn't check after I bolted it in and let the eng settle on it. It never occurred to me it would hit, but with all that's happened it would be par, would it not? Fk, now I have to go tear into it again and check before I drive it, out of fear I'll break the bracket... Fk Fk Fk!
Wow, sorry you're having to deal with all that. I was contemplating exploring aftermarket motor / transmission mounts for my 2010 550 to find something that might last a bit longer than stock, but after reading about your ordeal, I think I'll stick with stock. I'm not able to do my own work, so I can imagine the mechanic getting pretty pissed about something like this.
Can you just cut your losses and go back to stock mounts? Then demand a refund (or do a chargeback) for the non-functional mounts?
Update:
Since I don't want to tear into it without the correct bolt/washer to replace while I'm in there, but I'm overly curious about why this is happening, I decided to drive it. Very gently at first, and I was cringing because not only the steering wheel is vibrating, my feet are too. It felt like my heels were each resting on a hand held vibrator, just lower frequency.
Once on the road it wasn't nearly as bad. Then I let off the gas and it's vibe city again. Not as bad, however... I noticed it wasn't so much rpm, but how much the motor was leaning on the mount. When I give it enough gas to take all the weight off the mount, vibes basically vanish. Decelerating or idle, which puts full weight on the mount, is where it's the worst. I guess this would be expected since I still have the oem mount on the right, but what's interesting is it's getting better as I go. After after a good 15min of pulling/pushing on the mount, and not exactly smooth roads to bounce on, vibes are less than half as bad as it was. Still too much, but now the metal to metal theory has some weight to it because with use it would be mushing the contact point down. It would also have diminishing returns, which is what I'm seeing. A much larger improvement the first mile, less as I go, and no improvement that I can tell in the last couple miles.
Also, spark retard only reacts to noise above a certain threshold, so halving the vibration would drastically reduce or eliminate it, and that's exactly what happened. In the first mile retard was less than half. Now retard is maybe 10% of what it was. If I can reduce vibes to an acceptable level I'd imagine retard will go away altogether.
I hope this is a metal to metal issue because I can simply grind away the offending area and it should perform like people claim. Looking at the remaining VRP mount and the oem I removed, I don't think the VRP could make contact? The VRP is 4mm lower than the used mount, but I assumed the oem compressed by that much and the net height is basically equal? Maybe not, but time will tell.
So my latest plan is to find the correct bolts and washers, then dig the mount out. If there's metal contact, I'll fix it, replace bolt, and I should be good? If no metal contact then I have some thinking to do, like why did it change with use and how to tame it to be acceptable? Because as annoyed as I am, I also love a challenge and really do want it to work.
nkx1: I'd say don't buy oem mounts just yet, let me see what I find, which will hopefully be this weekend. Plus you have a different engine and I'd imagine you do not have the horizontal adapters? So in yours I'd imagine they work as well as everyone claims?
To quote the op “This is lot of lost personal time, and I guess I'll have to wait and see if VRP says it's also a lost $500. At the very least, maybe some others will learn from my mistake.”
Thank you. Most of us know to stay away from anything VRP related. Hopefully they don’t blame you for all of their continued problems, as they like to attack customers instead of help them. Always remember to research the forums before buying into aftermarket, there are lots of copycats out there with no real qualifications. We are all drawn to pricing, but the value isn’t there when the customer service is horrid.
Good luck in your quest for motor mounts. I stick with stock with my p30 63 wagon.
Update, per WRC's request
The dealer doesn't have the bolts... Gotta buy the whole mount if you want one. So I went to a place that specializes in bolts and the closest they had was in the pix below, which I had to buy a box of 50.
Also in the pix below is the Mica washer. The old one showing that it cannot be removed, per my hack mark, and you see it's literally falling apart just sitting there. Plus a brand new one on a new mount, which also will not come off because you can see the glue at the inner and outer edges. I'm sure they glued it because it would otherwise end up broken. I assume Mica was used to minimize heat transfer, because why else?
The old Mica appears to be ~.047", so I assume originally 1.25mm. I don't have any Mica sheets, but just realized I do have some G10 sheets, somewhere. Who the hell has G10 sheets lying around? I do!
As for the bolt, its head needs to sit in the adapter low enough so it won't interfere with the nut above it. Sorry I didn't take a nut pix when I had it out but you can figure it out from the pix above showing the adapter with and without the nut. The oem bolt head is 6mm high, just short enough to be out of the way. The new one is 10mm. The Allen part is maybe 5mm deep so you can see the problem... So I'll shave a one down and see how it looks, and if not enough meat for the wrench I'll make it a slot head, and fab a tool to drive it.
Meanwhile, I drove it again today and it isn't getting any better. It does have some nice beenies because it feels tighter, the car overall that is, so I guess the eng was flopping around more that I realized and making it feel sloshy? I remember my truck being tighter too, but not nearly as much as this. So performance wise they (it) seems awesome, just gotta tame it. Now I'm wondering if that one mount is netting me 90% of the bennies, which is pretty much what I assume, or is there a good chunk more to be had if I do the other mount? I'm probably the only one in the world to run just one so I doubt there's anyone to ask. Guess I'll just have to do it and find out, after I soften the mounts up.
yah mica sheets nope..lol .... Wait would those G10 be resistant enough to engine heat?
For fasteners, I use Threads of the South (TOTS) or Grainger or McMaster-Carr. Last two will deliver locally ( to me ) or i can go pickup. They are nationwide and carry a huge amount of varieties incl stainless and titanium (IIRC) TOTS will prolly ship as well just never tried as they are only 4 miles away. Fastenal might work for u too.
Titanium washer in that size would not be affected by the heat. Plenty of brakes use titanium shims to block heat transfer to the calipers. You might get some ( IIRC $50 for a pair. . easily cut with dremel. MOL
Yah get them both done once you get it figured out. Should be night and day,
I stuck with stock OEM for my A207 E350 whne it was time...didnt want any hassle or much fettling....
The G10 is good for something like 4 or 500F. I forget exactly but it's plenty.
I did order some McMaster bolts. Not the ones you linked, but some Torx Pan head that I'd still need to trim the OD of the head down, but the height was good. Plus stainless. I just assumed they would not make it by the weekend because when I order from them at work it takes 1-2 weeks before I see it. Most of that being red tape from work but we'll see what happens. So buying there and locally was to increase my odds of a usable bolt.
I modded the bolts I have and they came out with enough meat on the Allen to drive 'em home, per the pix. No doubt I'll use the others if they show up, since they're stainless.
I currently have the other mount apart so I can modify it. By design it needs some slack inside or it'll vibrate more, and when initially assembled there won't be any slack at all because there's also a butt lode of stiction so it's tight as hell going together. Unless they cycled them at the factory, which they should do, but I doubt it. Being tight is far more likely than my metal to metal theory, and while I'm almost certain it was tight, I can't imagine it was causing all that it did, or the spark retard. So it's theory # 2, for now.
That's also an fyi for anyone using these: You need to brake torque the motor both ways a few times to sure they're freed up and have that internal slack. I'd say do it manually before install but those puppies are friggin tight!
I still gotta brain out softening them as best I can without weakening them. I'm sure the vibes are not only up/down, but also side to side, so I'll try to tweak it both ways.
Those look better . McMaster Carr is my goto along with Grainger or Threads of the South! I guess im lucky to have all three in Atlanta.
Yeah you 'll need to figure out the vibration thing but it should be better once you get both in, To all reading... yep testing the mounts after to ensure properly located by brake torquing the motor in gear ( forward and reverse ) with a little bit of throttle should help. Its what us old fashioned guys do in the first place to check if the car has collapsed mounts. And in the latter case the engine will move hugely so be bloody careful :-)
Re softening them....maybe try drilling several 1/16 " holes in each.
Anyways Chevota, once done, please post up your opinion on these versus OEM or anyone considering aftermarket stiffer ones
I'm experimenting with soft silicone to use in the mounts (A10 level soft) to soften the vertical vibes, plus some alterations to the urethane to soften horizontal vibes. Not sure how much horiz is contributing, but I suspect a lot.
Since last time I posted it seems to vibe a little less, but I may just be getting used to it? Doesn't matter because it's still too much.
Pix below will help understand the mount, and what I plan on doing to it. Basically that stack of discs is a tight fit in the mount, but note that air gap between discs 4 & 5, which allows the inner piece of Alum to move up/down a bit. So there's that slack, plus whatever the urethane gives. So a little over 1/8" of slack and whatever the give the urethane allows. I'd like to reduce the free slack, but I'll make it more flexible so it's still free to move a bit. The slack is there for a reason because if no slack then discs 1-6 would add some to the compression stiffness. As it was made the Alum inner can slide through discs 1-6 and only put downward pressure on discs 7-9. Then when pulling on the mount it only pulls on 1-4.
I will also be lubricating the guts so it can more more freely. As it came it was tight as hell, but now with a bunch of discs missing it'll move a lot easier, but I wanna help it a bit more. Plus make assy easier. No lube between discs, only a very very thin coat on the outermost edges, and only on the urethane. Note the discs in the first pix are not in order. I guess I should take better pix...
The silicone I'm adding shouldn't affect the horizontal vibes much at all. It needs horiz support so I have to use the stronger urethane, but modifying and/or removing some urethane discs will make it softer horizontally. I figure it doesn't need to be as stiff as it was. My only real concern is the point where the horizontal bolt on the top bolts to the engine, which is clamping the eng to the very top of the mount. It would take a lot of force to upset it but if the eng/car shifted left or right hard enough, the clamped contact point could shift. Then the mount would be bound up a bit inside. Making it softer horizontally means that could happen more easily. It's really an odd setup, that horizontal adapter piece I had to recycle, and imo a shortcut fix. I don't believe anyone would chose to make it this way, but time is $ and I guess they said it's good enough. Besides, they have to spend their time making other things overly complicated.
With any luck I will install the left one this weekend. I kinda want to do both at once but then I won't know how well the modded mount worked. And it'll be less work if it's a fail and I need to redo it. They're almost two separate jobs so not a big deal to divide it up.
I should also do my O2 sensors, that I bought nearly 2 years ago, but I swear they made the plugs as difficult to reach as possible so I've been blowing it off. Even when under it doing the the mount last time, I said screw that. But I'm getting a readiness monitor "Oxygen Sensor Heater - Incomplete". No code to tell me which one, of course, so it may be in vain, but smog is past due now so I should at least try.
Mount body with guts in and base plate showing steps inside.
I added that little hole in the center of the base plate to prevent air from upsetting things.
Nice work sir!. Thanks for the description and the why of what you did... Hope it lasts and works to reduce all the noises and also to prevent any engine shifts.....Please post up once its all done with your evalution !!
Update: Works great! Vibes at idle are virtually gone. If I wasn't looking for the vibes I'm not sure I'd notice, so that's pretty good. Still some vibes at 1200rpm, but drastically reduced.
There was no metal to metal contact so it must've been all been urethane. There is still very little room between the edge of the Alum center, where the adapter sits, and the engine bracket. This is where I thought it might've been hitting since I noticed before how little room there was. So little, that I fabricated a heat blanket from scrap material and it was getting crushed during install. I pulled the blanket out of the way and problem solved, so fyi for anyone wanting a blanket or shield. Not sure if I need a blanket, but I figured I might as well since I don't know what the silicone will do under who knows what temps. Now I wonder how well it's holding heat in. I'm now picturing cooling fins on the base on the mount, which is totally doable but I'm not pulling it out just for that.
It seems this clearance issue is why the circular base of the adapter has a big spot cut out. If not, you wouldn't even be able to install it. Had I been willing to take the mount out again, I would've shaved some meat off the corner of the VRP just to be sure it'll never touch. I'm sure it's fine, I just don't like it. That big nut nut only goes into the adapter one way, and the little tit on top of the nut only fits into a cutout in the eng bracket one way. So between those two it ensures the adapter is facing the correct way. Seems like it would be easier for MB to notch the eng bracket, but whatever.
I brake torqued the mount a few times with the hood open and it seems as tight as it was before, and certainly much tighter than the orig mount. The guts of my version do allow a little more flex when pulling on it, but I also removed most of the slack it had that allowed the Alum center to slide in/out of the urethane, so I think it balanced out, or might even be tighter. The slack was needed as it was, but I think it may have been excessive? Plus mine needs less slack, so that's why I removed most of it.
My version also sat ~1.5mm taller than the unmodified one I removed. I made it as tall as was reasonable since the silicone will compress more and I think should end up about the same.
Now I just have to cross my fingers and hope the silicone lasts. I don't see why not, but time will tell.
Here's a better pix of the adapter, new bolt, and horizontal nut where the top part of the nut appears to be a cover. You can also see the radius of the corners where the nut to slide in. And you can better see why the head of the bolt connecting adapter to mount needs to be custom to both fit in the recessed hole and clear that nut on top of it.
The G10 washer between the mount and adapter needed to be ~.025", not the .050" I thought. Maybe the VRP has less room for the washer? Luckily one of the G10 sheets I had was .024" and basically perfect.
The drama continues:
When I installed them I thought the bottom bolts were a little tight. Not cross-thread tight, but tight like a crappy bolt would feel on fine threaded aluminum. So I pulled the bolt out after a turn or so, no alum on the threads and the bolts looks fine. I look up in there to be sure it's aligned right, and it's good. So I continued. A turn or two later, still feels too weird, so I pull it out again, and again no alum on threads. Hmmm... I guess it is what it is and I finish.
Well, now that it's out, it was cross threading. They tapped them too fine. I also compared them to my older E350 mounts and the VRP are finer in both cases. So it's not an odd-ball bolt unique to my car.
If you look very closely you can tell the threads in the foreground look ever so slightly different from the unused threads at the far end.
Can you chase that with a tap and restore it? or will those need replacing? Either way you have to get the matching thread on the bolt and the mount . Why in blazes would they use a finer thread? Prolly like a 1.0 mm pitch rather than 1.25 or 1.5 mm?
Looks fubar to me, so I need new base plates or a repair kit. I'd be happier with a kit, especially nice fat keenserts. I could run a longer bolt and nuts, but dont wanna.
Last wednesday I emailed VRP that the threads in the base were wrong. They replied asking if I had threaded bases or not. Not sure what to make of that but maybe an AI is replying to emails for them? I'm sure that'll work out for them.
I replied, but now crickets. Figuring I'm on my own, I ordered a helicoil kit.
In post #19 I mentioned it was so tight in there that the heat blanket I fabbed wouldn't fit between mount and eng bracket. Seems this guy had the same issue and had to do the same thing to fix it. See the pix in post #1: https://mbworld.org/forums/w212-amg/...nt-review.html
12-31-2023, 04:45 AM
