Rod bearing replacement - UPDATE

[mr wilks]

Is it my cross eyed vision or is one of the motor mount far more compressed than the other one?

I always thought that if you had that much copper colour showing they were beyond the point of "not too bad"?

The copper cladding is technically a part of the wear surface. It is there for having also good wear/running properties. The white metal top coat is an initial wear layer.
For instance, these are rodbearings from (I think) a Ford:

Some copper is showing. But as these are rodbearings after 195k miles (thats what the guy said/wrote) theyre not too bad and probably will go on for 100k miles (or more).

But the s54 is an engine with a very well documented history of rodbearing wear and some catastrophic failures (probably mostly track related or high speed autobahn cruises) that you dont want to take any risks with it. That puts it in a different perspective. And maybe that guy has seen much worse, that also sets your expectations :roll:

Both mounts compressed the same, it's just the angle their sitting at that's gives the impression one is more compressed then the other.

It covered 39k before you got hold of it though so you have no way of knowing how it was treated until then :?

 

[Viren]

Is it my cross eyed vision or is one of the motor mount far more compressed than the other one?



The copper cladding is technically a part of the wear surface. It is there for having also good wear/running properties. The white metal top coat is an initial wear layer.
For instance, these are rodbearings from (I think) a Ford:

Some copper is showing. But as these are rodbearings after 195k miles (thats what the guy said/wrote) theyre not too bad and probably will go on for 100k miles (or more).

But the s54 is an engine with a very well documented history of rodbearing wear and some catastrophic failures (probably mostly track related or high speed autobahn cruises) that you dont want to take any risks with it. That puts it in a different perspective. And maybe that guy has seen much worse, that also sets your expectations :roll:

Both mounts compressed the same, it's just the angle their sitting at that's gives the impression one is more compressed then the other.

It covered 39k before you got hold of it though so you have no way of knowing how it was treated until then :?

Although true I did investigate the history (which was good) and it had the original front tyres and brakes so couldn't have had that hard a life. But yea your right you never know. I would have thought if it had been ragged from cold the bearings would show signs of scars or deeper scratches, however the wear was nice and even.

 

[mr wilks]

Both mounts compressed the same, it's just the angle their sitting at that's gives the impression one is more compressed then the other.

It covered 39k before you got hold of it though so you have no way of knowing how it was treated until then :?

Although true I did investigate the history (which was good) and it had the original front tyres and brakes so couldn't have had that hard a life. But yea your right you never know. I would have thought if it had been ragged from cold the bearings would show signs of scars or deeper scratches, however the wear was nice and even.

Having the original front tyres & front discs doesn't really confirm a well kept car :?
We all take a gamble with a used car especially high performance ones but at least you have removed a potential big issue by having the shells replaced so that can only be good for you going forward with the car

 

[Viren]

Those of you who have had your bearings replaced, what has been you "break in" procedure. Seems to be mixed school of thought. Some say no break in is required as there is no contact. Some say more than 1k of break in. Interested to hear views, I'm thinking keep it under 3-4k for 500 miles. Change oil at 1k. But that's just a complete guess based on what I've read so far.

 

[hopz121]

I was going to do the keep it below 4000 rpm for 1000 miles then drop the oil but I honestly don't know what is right or wrong if I am honest.

I look forward to the responses

 

[FD3S]

Those of you who have had your bearings replaced, what has been you "break in" procedure. Seems to be mixed school of thought. Some say no break in is required as there is no contact. Some say more than 1k of break in. Interested to hear views, I'm thinking keep it under 3-4k for 500 miles. Change oil at 1k. But that's just a complete guess based on what I've read so far.

My indie told me 500km under 3.5k. :roll: No change of oil after that. I do not see the point to change the oil again after the rod bearing change.

 

[Z4M-2006]

You can't change the oil often enough on an S54

For the price it costs to do it , then why not..?

There will certainly be contamination of the oil as the new bearings bed in..

 

[TomK]

Yes I was told to drop the oil also after 1K or so, and not to go too crazy for the first few hundred miles.

 

[Viren]

Sounds good, so keep it nice and easy for 4-500 miles then back to opening the taps. It's so frustrating driving this thing under 3.5k. I'm trying to rack up those miles quickly. Was out yesterday on the A1 doing this and had someone in same car/colour pull up alongside. My right foot wanted to twitch so much!

 

[zomby]

When I had my bottom end done I was also told to keep it under 4k for the first 500 miles, at which point I took it back to the garage for another oil change. They said it was more precautionary than anything, but after having all that work done it can't hurt to be prudent!

 

[Viren]

I'm getting a noticeable vibration in the car when pulling away at low speed and when the engine revs drop below 0.75k. Does anyone have any experience with this post fiitting vibra technic mounts? Completely fine above 1k.

 

[Smartbear]

Those of you who have had your bearings replaced, what has been you "break in" procedure. Seems to be mixed school of thought. Some say no break in is required as there is no contact. Some say more than 1k of break in. Interested to hear views, I'm thinking keep it under 3-4k for 500 miles. Change oil at 1k. But that's just a complete guess based on what I've read so far.

If there's no contact then how does the wear occur? Something's rubbing against those shells to make them look like that :wink:
Rob

 

[srhutch]

I would be doing a running process the same as if new, with oil change around 1,200 miles.

 

[Viren]

I'm getting a noticeable vibration in the car when pulling away at low speed and when the engine revs drop below 0.75k. Does anyone have any experience with this post fiitting vibra technic mounts? Completely fine above 1k.

Ok so went for a quick drive, I'm getting a very noticeable vibration when I engage the clutch let the car run in 1st gear but do not give any gas. Like coasting in 1st. Is this a symptom of vibra technic or unusual?

 

[Steve84N]

Those mounts do vibrate at very low revs, not quite sure why you're running below 750rpm tbh though. I have a slight bit of vibration at idle but on the move there is no perceptible increase in NVH. My comments are based on the road version so if you went for the track it'll be worse.

 

[GuidoK]

Same with me (also road mount), I only feel slight vibration on idle; 750rpm.
However I never drive at that rpm, unless in traffic when I have to coast at idle, doing like 1or2mph.
But my impression is that its rpm related; at 900 or so its already gone.
The vibration also isnt really harsh. You mostly feel it on the side of your leg, resting against the drivetunnel.

 

[Viren]

Does anyone know the torque for the mount bolt?

 

[Steve84N]

About 45nm iirc, not that much really.

 

[FD3S]

Before 3 days I have done my rod bearings replacements and changed also my mounts with Vibra Technics Road version. The car at cold start has vibrations and has no comparison with stock mounts. However within the first mile the vibration gets reduced and disappears. My car has idle at 950 rpms however. Also the car feels more robust on the gear changes but that can be also a placebo effect.

 

[Viren]

Before 3 days I have done my rod bearings replacements and changed also my mounts with Vibra Technics Road version. The car at cold start has vibrations and has no comparison with stock mounts. However within the first mile the vibration gets reduced and disappears. My car has idle at 950 rpms however. Also the car feels more robust on the gear changes but that can be also a placebo effect.

So to be a little more clear sometimes when pulling away up hill if you don't give enough gas the revs drop a little and I feel a vibration throughout the car (the cars idle is perfect, no issue with that, just the vibrations). Also when pulling away like normal there is an initial virbration. It has been getting gradually worse and I've booked the car in to have it looked at. Will let you guys know what the problem is.