Bad cps, low battery or something more nefaste ?!

[philly98540]

Yeah those pics are too small to see what's what. If I'm reading this right, the main timing chain is busted? If so, you bent a lot of valves and heads need to come off. Maybe prepare to put compressed air in each cylinder to verify what valves are toasted.

[Chedley]

I am still in the process of tearing down the engine front -- man, it is quiet a job for a solo DIY'er-.!! I will post larger pictures as I collect them

But for now, yes, the plastic guides and the main timing chain broke off -- portion of the chain hanging on the oil pump, and chunks of plastic guides all over the oil pan and pump-

So, If I get your drift right, first, you recommend running a compression test (with a cylinder leak-down -tester ?) to find out bent valves --if any- and test piston rings, ?? Basically to determine if the engine is salvageable or not, before proceeding on replacing the Timing chain and guides. Yes ??
Your honest advice will be appreciated in advance. Thanks,...

[BimmrMeUpSnotty]

Let’s put it this way, Chedster, it won’t be a quick trip to the Ace Hardware for a stiffer tension spring.

[wagons ho]

Broken chain. It's so done.

[philly98540]

I am still in the process of tearing down the engine front -- man, it is quiet a job for a solo DIY'er-.!! I will post larger pictures as I collect them

But for now, yes, the plastic guides and the main timing chain broke off -- portion of the chain hanging on the oil pump, and chunks of plastic guides all over the oil pan and pump-

So, If I get your drift right, first, you recommend running a compression test (with a cylinder leak-down -tester ?) to find out bent valves --if any- and test piston rings, ?? Basically to determine if the engine is salvageable or not, before proceeding on replacing the Timing chain and guides. Yes ??
Your honest advice will be appreciated in advance. Thanks,...

yeah, don’t bother taking much apart till you assess salvageability of that engine. Valves are definitely bent, so likely both heads off type repair job with all the incidentals. Going that far is likely not worth fixing it depending on what engines you can locate on the market.

You can take valve covers off and rotate cams so lobes are pointing up on each cyl and test with compressed air going in via and adapter screwed into that spark plug hole. Listen for air leaking into intake and exhaust to tell which valves are bent. You will likely bend more valves in the process so scrap that. Just look for another engine or commit to taking heads off and doing the full head job and guide repair. That is if a piston ain’t fubarred.

[Chedley]

Thanks for the reply.
Is there a way to find out if any piston is fubarred or not beforehand??

[philly98540]

Thanks for the reply.
Is there a way to find out if any piston is fubarred or not beforehand??

You can borescope them through the spark plug holes.

[wagons ho]

Locally, among the BMW mechanics, I have picked up every m62 and tu motor that has been swapped out after failure.
I have torn down 20 or so engines, looking for rebuildable cores (non scored blocks).
The one failure that I come across repeatedly is on engines that had heads rebuilt after guide failure.
****** Scored bores ******
So I started looking at engines with guide failure with bent valves to find the cause.
When the piston hits the valve, the interference wedges the piston in the bore, which causes the piston at the ring land to smear metal.
This smear holds the ring in the land, and while everything looks ok, when put back together, the ring cannot float, and scores the bore.
The history on these motors shows less than 1000 miles from guide and head replacement, to compression loss.
So, in my experience, every bent valve motor requires the piston to be pulled, just to check the piston.
Now that adds massive amount of work to the job. Plus tools. And parts money. And time.
So the engine is totally junk, unless you strip it completely down to check everything.
I find it ironic that the proponent of tensioner changing to prolong guide life is now faced with a destroyed engine from guide failure.
Can I say told ya so?

[R Shaffner]

What a bummer. Chedley, I'm so sorry to hear it's this bad.

The guides on my first 540 failed at 206,000 too. Luckily for me they failed suddenly one morning as I started the car. Stopped it immediately, so the engine was OK. (But that car was totaled 2 years and 30,000 miles later by a texting driver.)

I hope you can find a nice engine with fewer miles looking for a good home.

[philly98540]

Locally, among the BMW mechanics, I have picked up every m62 and tu motor that has been swapped out after failure.
I have torn down 20 or so engines, looking for rebuildable cores (non scored blocks).
The one failure that I come across repeatedly is on engines that had heads rebuilt after guide failure.
****** Scored bores ******
So I started looking at engines with guide failure with bent valves to find the cause.
When the piston hits the valve, the interference wedges the piston in the bore, which causes the piston at the ring land to smear metal.
This smear holds the ring in the land, and while everything looks ok, when put back together, the ring cannot float, and scores the bore.
The history on these motors shows less than 1000 miles from guide and head replacement, to compression loss.
So, in my experience, every bent valve motor requires the piston to be pulled, just to check the piston.
Now that adds massive amount of work to the job. Plus tools. And parts money. And time.
So the engine is totally junk, unless you strip it completely down to check everything.
I find it ironic that the proponent of tensioner changing to prolong guide life is now faced with a destroyed engine from guide failure.
Can I say told ya so?

Interesting and I’ve learned something new. That smear of the ring land!

Sage advice here. Search out a new engine!

[Chedley]

What a bummer. Chedley, I'm so sorry to hear it's this bad.
....
The guides on my first 540 failed at 206,000 too. Luckily for me they failed suddenly one morning as I started the car. Stopped it immediately, so the engine was OK. (But that car was totaled 2 years and 30,000 miles later by a texting driver.)
...

@R Shaffner-->
Well,.. I am basically in the same similar situation.

The guides failed --as evidenced by that cement mixer funky noise- upon starting the car in a parking lot. I drove about 1/2 mile with that noise, slowed at the exit, and the engine died. So I tried to restart : no go. I got into the crank-no-start scenario, but I did not and could not drive one inch.
So I had the car towed home, and started looking into it.
I did find a broken chain still hanging in the oil pump, and chunks of guides in the oil pan. So I know the chain and the guides broke.

I am no mechanic really, but I am a bit startled by these assumptions of jumped tooth, bent valves, blown engine,,etc.. and wanted to be sure about it before I embark on replacing the timing chain, guides, vanos, timing and what-not.... Or junking the whole engine. ?

What do you think ??

Thank you all for the advice.

[R Shaffner]

@R Shaffner-->
Well,.. I am basically in the same similar situation.

The guides failed --as evidenced by that cement mixer funky noise- upon starting the car in a parking lot. I drove about 1/2 mile with that noise, slowed at the exit, and the engine died. So I tried to restart : no go. I got into the crank-no-start scenario, but I did not and could not drive one inch.
So I had the car towed home, and started looking into it.
I did find a broken chain still hanging in the oil pump, and chunks of guides in the oil pan. So I know the chain and the guides broke.

I am no mechanic really, but I am a bit startled by these assumptions of jumped tooth, bent valves, blown engine,,etc.. and wanted to be sure about it before I embark on replacing the timing chain, guides, vanos, timing and what-not.... Or junking the whole engine. ?

What do you think ??

Thank you all for the advice.

All the advice here is good. The point is that once the chain breaks, the timing (meaning the precise positioning of the crank, pistons, cams, and valves) is lost. This is an "interference engine" which means the pistons will hit the valves if they're still open when the pistons reach the top of their strokes. The chain almost certainly broke while everything was still spinning, which caused damage to most if not all the pistons and valves. (Getting off timing, and causing all that contact might have been what broke the chain.)

The easiest ways to check this would be with a 'scope in the plug holes, or you could pull the cam covers, see how far out of position the cams are. You might also see that some cam lifters are not touching the cam (meaning they're over bent valves).

I'd def look for another good engine before trying to fix one that's been so damaged. Cheaper, easier, and better over the long run.

[wagons ho]

Hey Chedley, you won't address me, but really, I'm trying to help. I don't want to see you wasting time and money on your current motor as it's toast.
But this situation was brought on by your constant mantra on timing tensioner saving you from guide replacement, until it became a source of amusement. But more importantly, I didn't want new people to the site to believe it, as you have 1500 posts, and might come across as an authority.
Let's go back and look at my favs.
.Screenshot_20220929-112919_DuckDuckGo.jpg
Screenshot_20220929-112933_DuckDuckGo.jpg
Screenshot_20220929-075257_DuckDuckGo.jpg
Screenshot_20220929-075054_DuckDuckGo.jpg
Screenshot_20220929-074718_DuckDuckGo.jpg

Now, your going to need a motor, Gresham auto recycler has some usually.
And do the guides and a reseal before you install it.

[BimmrMeUpSnotty]

Baaahaha! Can’t believe you actually saved all that gibberish about the tension springs he’s been blabbing about. He’s just gonna kill the next one.

[wagons ho]

I didn't save them, just screenshot them to avoid posting links.

[philly98540]

Let Ched look for an engine in peace already. Hopefully he is successful. His belief in the spring was seen through by most.

[JimLev]

Funny that the spring he was using actually had less tension than the INA spring.
I wonder how much that contributed to the guides failing.
Getting 200K+ was still pretty good. To bad the chain broke, that deep six’d the engine.

[Bmwe39528i1998]

Any updates? Kinda curious...did you find another engine?

I'm planning on moving to 540i from my 528i and the biggest concern is those guides.
A lot of people say they've replaced them. Any way to know if they've been replaced for real, prior to purchasing the car?
Looks like the lifespan is about 300km on them

[R Shaffner]

The saga continues here:
https://www.bimmerforums.com/forum/s...debunked/page2

And here:
https://www.bimmerforums.com/forum/s...(BMW-E39-540i)

For your question about knowing whether guides have been changed:

The parts of the guides that wear down the most are hard to see (especially at the bottom of the center U section). I suppose if you could see grooves right where the chain first touches a guide, like going into the U from the passenger side cam, then you would know they were not recently changed, since those areas wear more slowly.

Best way to tell that the guides do need to be changed is to find pieces of the guides missing or in the oil pan. Also, if a plastic section has shifted in its metal holder, in the direction of the chain's travel, then you know it's broken elsewhere and needs to be changed.

(I changed mine at 190,000 miles -- they weren't making noise but I knew they had to be close. When I got the cam cover off the driver side, I could clearly see a guide piece from the U section that was being pulled up and out by the chain. That meant it was broken off down below. There was basically no more plastic in the bottom of the U section. Later I found many pieces in the pan and the oil pump filter. That meant that I'd changed them in the nick of time.

The key lessons from Chedley's experience: (1) Don't wait for them to fail. And (2), if they do fail, stop the engine immediately and don't run it or crank it until the guides are fixed.

[Chedley]

Any updates? Kinda curious...did you find another engine?
.....

No. It turns out there was no reason to look for another engine.
Other than the broken chain and guides and associated carnage at the front, the engine block structure sustained very well the breakup. So the engine is a keeper. Follow the saga in the above links if interested...

About movin g to a 540i, select one with the V8 M62TU engine double vanos -- That is post 1999 E39's 540i's I think --. Not the plain M62.

And as to the famous guides breaking down, well , that is like "taxes and death : they are inevitable". However, my experience showed that the lifetime of the guides can be extended to up to 207,500 miles -- your mileage my vary--, ...So not bad at all, but let's not restart the controversy now.

[Chedley]

Let me add that from a purely $ cost and time point of view, it would have been probably better to swap the engine with another "long bloc" engine....

[SW530]

Well, I checked the 5 fuses (30 A) in the DME box. They are all good.

Did you look at them to see if they were good, or meter them?

[JimLev]

Let me add that from a purely $ cost and time point of view, it would have been probably better to swap the engine with another "long bloc" engine....

You probably would have still needed to do the guides, just not all of the other things.

[Bmwe39528i1998]

Thanks for sharing your experience! I will try to look down to see of I can see the guide when I check out the car.

[Bmwe39528i1998]

No. It turns out there was no reason to look for another engine.
Other than the broken chain and guides and associated carnage at the front, the engine block structure sustained very well the breakup. So the engine is a keeper. Follow the saga in the above links if interested...

About movin g to a 540i, select one with the V8 M62TU engine double vanos -- That is post 1999 E39's 540i's I think --. Not the plain M62.

And as to the famous guides breaking down, well , that is like "taxes and death : they are inevitable". However, my experience showed that the lifetime of the guides can be extended to up to 207,500 miles -- your mileage my vary--, ...So not bad at all, but let's not restart the controversy now.

Hmmm interesting, I bet the valves were all bent?
And what about wagons ho explanation of scored bores?
Maybe it's been already addressed in the links posted, so I'll look there for continuation

Why do you recommend M62TU bs M62? I heard pre vanos is less issues and changing guides is easier as well.
I know that M62TU has a bit more power.