Z4M engine failure - repair and uprgrade advice

Beedub said:
OP i think you will REALLY enjoy reading through this, some great info and great pics too, may be worth registering and posting some questions to andrew lang,... The op in this link is at 200K on the original cams and followers, the wear on some of them visually flat.

http://www.m3forum.net/m3forum/showthread.php?t=547883
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Good read thank you. Looks like the lifter against cam is a common problem but nobody knows the cause which is a worry :(

Mine is currently having the valve clearances adjusted because they were all miles out when he measured them and haven't been done for a "very long time". Suprsingly on closer inspection he says my current cams might be ok and sorting the valve clearances might fix the car but I'm not as optimistic as him so I've ordered a set of Schrick DLC followers in advance.
 
tomTVR said:
Beedub said:
OP i think you will REALLY enjoy reading through this, some great info and great pics too, may be worth registering and posting some questions to andrew lang,... The op in this link is at 200K on the original cams and followers, the wear on some of them visually flat.

http://www.m3forum.net/m3forum/showthread.php?t=547883
Click to expand...

Good read thank you. Looks like the lifter against cam is a common problem but nobody knows the cause which is a worry :(

Mine is currently having the valve clearances adjusted because they were all miles out when he measured them and haven't been done for a "very long time". Suprsingly on closer inspection he says my current cams might be ok and sorting the valve clearances might fix the car but I'm not as optimistic as him so I've ordered a set of Schrick DLC followers in advance.
Click to expand...

Are they checking for flat spots on the followers at the same time. Pointless exercise otherwise. They will continue to wear down at a rate.
 
...and the surface of the cam lobes will be destroyed if significantly worn followers are left in situ (necessitating new camshafts and followers).
 
BMWZ4MC said:
...and the surface of the cam lobes will be destroyed if significantly worn followers are left in situ (necessitating new camshafts and followers).
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So if caught quick enough the cams could be saved?
 
but what is caught quick enough though.....

100 miles?? 2000??? 8000??? 20k?? how long can these withstand before the case hardening fails... thats the question.
 
srhutch said:
BMWZ4MC said:
...and the surface of the cam lobes will be destroyed if significantly worn followers are left in situ (necessitating new camshafts and followers).
Click to expand...

So if caught quick enough the cams could be saved?
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Yes. Mine were ok when the followers were shot.
 
Beedub said:
but what is caught quick enough though.....

100 miles?? 2000??? 8000??? 20k?? how long can these withstand before the case hardening fails... thats the question.
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This. I suspect it would be measured in tens of miles or perhaps early hundreds once the case hardening on one or followers is significantly deficient.

There was no chance of saving the camshafts in my Westfield once the followers were shot. The head on that engine had been fitted fewer than 10k miles previously (replacing the OEM head that came with the engine). That might seem like very low mileage, but the cam profile is very aggressive and it sees only track use.
 
Beedub said:
but what is caught quick enough though.....

100 miles?? 2000??? 8000??? 20k?? how long can these withstand before the case hardening fails... thats the question.
Click to expand...

Only an inspection of the engine would dictate, but if people are aware of this they may listen to their engine more and be able to prevent further damage. From what I have read when the followers go you are talking tens of miles with accelerated wear. So camshafts aren't going to last long, but could be saved by not driving further.
 
on my next shim service that i do at home, i think a thorough inspection of each follower a wise choice.... this year will see my cars most use in a long time. Really enjoying mine in the sun at the moment- took it to a meeting i had in telford yesterday and oh my.. felt amazing tbh , infact my sons off school today so we are packing up the Z4 and going for a picnic somewhere far!! REALLY far. Today will be his / our FIRST drive together in the car! father son bonding at its best???
 
I presume the hardened coating on the follower is too thin to be reliably read with a micrometer during a valve adjustment?
 
Mangozac said:
I presume the hardened coating on the follower is too thin to be reliably read with a micrometer during a valve adjustment?
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You would struggle to measure it anyway as its not parallel to the opposite face.

A visual check is the only way, but by then it's going to be to late as you would have heard it already.
 
Chaps I've finally got the car back today after various delays totally unrelated to the issues with my car. It turned out to be worn lifters, 3 of them had flat spots with one of them quite bad. I had them replaced with some new Schrick DLC coated lifters and a pair of immaculate second hand camshafts I got from a breaker. While it was in bits I had everything inspected, valves etc and it's all in good shape. Now it's all back together it runs perfectly. Was approx £2000 labour + £600 for the Schrick followers + £120 for the camshafts. Not a cheap fix but I'm just glad to have the car back.

I've just got a couple of small niggles. The a/c now doesn't work at all (it was cold as ice when I dropped it off) and the coolant temperature is more erratic and seems to get 'hot' easier (previously it would barely ever move once up to temperature) although it doesn't seem to 'overheat', straying just beyond the half way point of the guage in traffic. The fan engages just fine.

They had to remove the radiator to access the VANOS and I'm thinking I might have an airlock causing the hotter temperature but would that explain the a/c not working? Also can someone please show me where the temperature needle 'should be' once warm? It's been so long since I've driven my car I can't even remember!
 
Are you referring to the temp dial below the rev counter? That's oil temp not coolant, there is no coolant gauge unless you're monitoring externally? Generally once warmed with average driving that should sit at about 11 o'clock.
 
TomK said:
Are you referring to the temp dial below the rev counter? That's oil temp not coolant, there is no coolant gauge unless you're monitoring externally? Generally once warmed with average driving that should sit at about 11 o'clock.
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Yes I must mean the oil tempature then. Yes it's about 11 o'clock most of the time but it seems to rise to just past 12 o'clock in traffic or when you give it some welly. I'm sure previously it never moved.
 
tomTVR said:
TomK said:
Are you referring to the temp dial below the rev counter? That's oil temp not coolant, there is no coolant gauge unless you're monitoring externally? Generally once warmed with average driving that should sit at about 11 o'clock.
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Yes I must mean the oil tempature then. Yes it's about 11 o'clock most of the time but it seems to rise to just past 12 o'clock in traffic or when you give it some welly. I'm sure previously it never moved.
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That's a bit unusual then, you really need to be giving it some stick to get it past 12 in general. Sustained track running I see it up to 1 ish.
I've never seen it move in traffic noticeably.
 
TomK said:
Are you referring to the temp dial below the rev counter? That's oil temp not coolant, there is no coolant gauge unless you're monitoring externally? Generally once warmed with average driving that should sit at about 11 o'clock.
Click to expand...

actually..... to my knowledge the s54 engine doesnt have an oil temperature sensor? Only a coolant temp sensor (well... 2 actually one near the thermostat, and one in the return pipe, labeled "water/oil temp sensor", but it sits in coolant).
Can you point out where the oil temperature sensor is located?
 
GuidoK said:
TomK said:
Are you referring to the temp dial below the rev counter? That's oil temp not coolant, there is no coolant gauge unless you're monitoring externally? Generally once warmed with average driving that should sit at about 11 o'clock.
Click to expand...

actually..... to my knowledge the s54 engine doesnt have an oil temperature sensor. Only a coolant temp sensor (well... 2 actually).
Can you point out where the oil temperature sensor is located? I might be wrong of course, I dont have an s54 in my Z.
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I don't know the answer to that I'm afraid, but for sure the gauge displayed in the dash is that for oil temp.
http://images.hgmsites.net/med/2006-bmw-z4-series-m-2-door-roadster-instrument-cluster_100294410_m.jpg
 
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