Z4M engine failure - repair and uprgrade advice
- Thread starter tomTVR
- Start date
Beedub said:
Yes I think that would be a good idea, I have an A-frame and a tow car but it would probably rip the front bumper off. Would homestart breakdown cover take it? Give them a sob story about a 'loud bang'
Smartbear said:Hi, I don't want to be a harbinger of doom but that sounds more like an end knocking rather than cam/follower type noise-I hope I'm wrong
Rob
Well that would tally with what the first specialist said since they did give the top end a thorough inspection. Forgive my ignorance but if it's what you think, could it be repaired without needing a new crank? I'm resigned to a very big labour bill but if it needs too many new parts I might have to lay it up while I save
tomTVR said:Beedub said:
Yes I think that would be a good idea, I have an A-frame and a tow car but it would probably rip the front bumper off. Would homestart breakdown cover take it? Give them a sob story about a 'loud bang'
Smartbear said:Hi, I don't want to be a harbinger of doom but that sounds more like an end knocking rather than cam/follower type noise-I hope I'm wrong
Rob
Well that would tally with what the first specialist said since they did give the top end a thorough inspection. Forgive my ignorance but if it's what you think, could it be repaired without needing a new crank? I'm resigned to a very big labour bill but if it needs too many new parts I might have to lay it up while I save
If you have home start and recovery then yes you should be covered.
That's exactly how mine sounded when the cams/followers went a year ago, get it to someone who knows what they are looking for.
The follower fingers are hard to see in situ but you'll see the curved surface will be flat and the tips of the cams will have a thin line across them :thumbsdown:
The follower fingers are hard to see in situ but you'll see the curved surface will be flat and the tips of the cams will have a thin line across them :thumbsdown:
Has the noise be diagnosed yet? Hope its a simple fix..
Hi guys I have a big update. The car has been at specialist 2 all week and I've just been in to see them.
The problem is the cams/followers after all, they are totally worn out!
This is good news in that it's preferable to bottom end failure but it's still going to be a very expensive fix. It's frustrating because I had a set of low mileage finger followers which I sold when specialist 1 said the top end was fine (specialst 1 will be getting named and shamed if they don't refund their 'diagnostics' fee).
I have a pair of camshafts on my desk, I havent decided if I wanted to fit them or upgrade to stage 1 Schrick (if, upon professional inspection the ones on my desk are knackered then I will go stage 1 Schrick anyway).
I need some opinions quickly on the following:
Where is the cheapest place to get finger followers? Aftermarket are fine although the garage said something about them being the same part at the ones fitted to the 318ti (or it might have been the 320si)?
Can I install stage 1 Schrick/new followers without needing anything else?
Any other thoughts in general or regarding potential upgrades?
The problem is the cams/followers after all, they are totally worn out!
This is good news in that it's preferable to bottom end failure but it's still going to be a very expensive fix. It's frustrating because I had a set of low mileage finger followers which I sold when specialist 1 said the top end was fine (specialst 1 will be getting named and shamed if they don't refund their 'diagnostics' fee).
I have a pair of camshafts on my desk, I havent decided if I wanted to fit them or upgrade to stage 1 Schrick (if, upon professional inspection the ones on my desk are knackered then I will go stage 1 Schrick anyway).
I need some opinions quickly on the following:
Where is the cheapest place to get finger followers? Aftermarket are fine although the garage said something about them being the same part at the ones fitted to the 318ti (or it might have been the 320si)?
Can I install stage 1 Schrick/new followers without needing anything else?
Any other thoughts in general or regarding potential upgrades?
They (the cams) look fine to me, but it isnt looks that determine wear. Obviously you see a wear trace where the lobe has run over the follower. On that crossing line the wear is to be determined. If you feel a transistion you have to look deeper. Normal cams are nitrided (hardening process), and depending on what type of nitriding is used (on cast iron) the penetration depth is between 0,05mm and 0,3mm (normally its deeper, sometimes up to over 1mm but this is taking it on the safe side).
You could measure this with a straight edge and feeler gauge lint.
That is one way of determining how worn it is (as on these cams there is a clear path on where the follower touches the lobe and where it doesnt)
But I dont see any real pitting or marks that indicate wear in tolerance. Wear on looks (like shiny compared to matte black) is imho not a real sign of wear.
But on one of the lobes it looks like there is a knick?
Do you have any pictures of your followers?
If the tappeting sound came from your valvetrain, there has to be a clearance somewhere and a decent tech should be able to measure that.
But as you're not doing the work yourself its best to trust your mechanics judgement. I mean when you have the knowledge to judge wear on camshafts chances are that you also have enough knowledge to replace them :lol:
You could measure this with a straight edge and feeler gauge lint.
That is one way of determining how worn it is (as on these cams there is a clear path on where the follower touches the lobe and where it doesnt)
But I dont see any real pitting or marks that indicate wear in tolerance. Wear on looks (like shiny compared to matte black) is imho not a real sign of wear.
But on one of the lobes it looks like there is a knick?
Do you have any pictures of your followers?
If the tappeting sound came from your valvetrain, there has to be a clearance somewhere and a decent tech should be able to measure that.
But as you're not doing the work yourself its best to trust your mechanics judgement. I mean when you have the knowledge to judge wear on camshafts chances are that you also have enough knowledge to replace them :lol:
^yes but not all DLC coatings are alike. There are many different types and brand names. So getting the one that is specifically suited (tried and tested) for s54 followers might be not that simple. I'm sure that Schrick wont give away all the secrets for their specific application.
In that regard DLC is like 'paint'. Specific brands and types justify specific applications.
But it can be a very nice coating system. Very low friction so it might even relieve the forces on the vanos and chain a bit giving longer life :wink: )
In that regard DLC is like 'paint'. Specific brands and types justify specific applications.
But it can be a very nice coating system. Very low friction so it might even relieve the forces on the vanos and chain a bit giving longer life :wink: )
Mister T said:
Reactive Suspension don't deposit any DLC of their own as far as I'm aware.
We do some of their fork tubes with one of our DLC's via PVD magnetron sputtering.
As Guido says, Schrick will have done various tests to ensure the DLC is suitable for the application and I personally wouldn't risk coating my own cams/ followers even though I have access to do so.
I could take a good guess at who deposits the DLC for Schrick too.
I really wish someone could figure out the route cause of these failures as its becoming quite frustrating reading these threads.
Good luck with the fix OP.