Overheated M60B40 Experience?

[jehu]

Somehow in some manner for which I can not account I went over a large section of loose very heavy gauge cable like Romex on roids probably from a Utility pole... I had not see it till the events I will describe occurred tonight.


At one point on a 250 mile tour I began hearing what I hoped was just the fan shroud being struck by the fan blades... I examined it at idle but saw nothing other than what appeared to be a very slight artifact in the water pump /engine cooling fan shaft.. That did have some play when moved yet this noise persisted... I drove it some more and examined it again without seeing any thing
. near the end of the drive I heard a belt squeal and saw the battery Light appear. I pulled over for a few minutes and again saw nothing obviously amiss. The idler pulley turned the belt seemed ok so I decided to see if driving it would clear it up... well in a few feet I saw smoke trailing behind and smelled what I knew was the belt...

I drove it for about 90 seconds max till the Coolant temp message appeared. I had the console illumination dialed down to possibly allow less battery drain without the alternator charging and did not see the needle which had pinned to the limit. I pulled right over and shut it down.

I opened the coolant res cap a little to allow pressure to escape and I sat for about a half hour till the engine temp was back to normal and called AAA but cancelled that call because they were going to take a long time to get there and I was just a mile from the NH State line where I knew I'd get faster service so I headed up the road at about 50 MPH in 6th gear till I saw the needle begin climbing and pulled over again and shut it down.

I pulled into a dirt driveway and the right wheel was in a slight depression. I opened the coolant cap again and this time took it up and coolant burbled out. I waited another half hour or so, added what little coolant I had in the trunk and tried once more watching the temp needle carefully. I mention the depression because when I was pulling out I heard something dragging underneath which I guess turned out to be this cable

It did not climb again when about a mile further I came to a gas station and pulled in. I shut it off, bought a gallon of 50/50 and filled it up. As I was walking around trying to decide what to do I saw something hanging from underneath the car. I pulled what you see in this picture out from the headers. After removing this the noise which had vexed me earlier was gone so it seems this thing had been making contact with a pulley or the crank and eventually worked its way into the belt causing it to jam and melt.

Finally I called AAA back and its on its way to a shop. I checked the pulleys and they all turn freely so I am hoping all I'll require is a new belt and the 90 seconds or so of over heating left me unscathed.

Does anyone think I will find myself this fortunate?

Anyway it looks like I had my phone in low power mode or something and it didn't actually create the image even though it told me it did so just have to take my word for it that it was is absolutely gargantuan gauge chunk of cable

[theBMWbeast]

If it is of any consolation, I had a similar situation with my old e38 740il.

Belt tore or something right after I left where I was (aka cold engine). Necessity dictated that I continued to drive the car until the battery light came on, needle was starting to creep, and I decided that it was time to get off. Had to get off the freeway, drive down some side streets, and then find a suitable place to park where I could leave the car overnight. It’s been a couple years since then, and the car is long gone, but the aftermath of all that was me replacing the water pump and belt. No head gasket problems that I remember. It’s an anecdote, for a m62 and not a m60, but in my case all was good. I do not believe these engines “like” to blow head gaskets, like an m30 for example. Obviously you’ll know when you know, but I vote rest easy and worry about the problem if there indeed is a problem.

[jehu]

I did the usual google search and the thing that spooked me was a few statements about Aluminum heads being especially vulnerable to the heat and one post i found just flat out said if your coolant boils your engine is guaranteed junk.

I did run it a bit just to hear its general sound while parked just for a few seconds so the oil had a chance to circulate but of course with the water pump belt off the coolant wasn't circulating so the fact the oil looks fine may not mean anything until a belt goes back on and I get to drive it again... the M62 also has aluminum heads right? So sure I'll take this and let it allow me to get to sleep ,lol..

If it is of any consolation, I had a similar situation with my old e38 740il.

Belt tore or something right after I left where I was (aka cold engine). Necessity dictated that I continued to drive the car until the battery light came on, needle was starting to creep, and I decided that it was time to get off. Had to get off the freeway, drive down some side streets, and then find a suitable place to park where I could leave the car overnight. It’s been a couple years since then, and the car is long gone, but the aftermath of all that was me replacing the water pump and belt. No head gasket problems that I remember. It’s an anecdote, for a m62 and not a m60, but in my case all was good. I do not believe these engines “like” to blow head gaskets, like an m30 for example. Obviously you’ll know when you know, but I vote rest easy and worry about the problem if there indeed is a problem.

[bennyg]

I ran my crapper 540i without a main fan for a couple years, it didn't overheat but the temp needle would start to creep up on a hot day after a minute stopped at red lights... but the main time was when the upper hose popped off on the freeway and it puked itself dry before the hi temp warning went off, I had my toddler in the back and it was nearly 40C so had to nurse it back with only the ~1L I had in the boot at the time, soon as I got home I filled it and idled for a few mins to cool the block.

That was ~4 yrs ago, didn't have to change anything (other than the rad which was already past due), no HG issues (I changed the oil a couple days ago and had a good look before road tripping it 700km)

[401michael]

My car would overheat if it sat in traffic for too long. Im talking 15 minutes in the same spot heat soak. However, I think you're okay if you shut it off before it got too hot and you let it sit then I dont see why it would have a blown hg or anything like that. check your alternator since the battery light came on. I couldnt see any photos posted so im not sure what cable you mean but dont forget these m60s have an electric auxiliary pump and fan so if the battery got weak that could affect the cooling. make sure you dont have a bad clutch fan either.

[Thomas525]

Engines are not delicate. This is a minor matter in the scheme of things. Just a tip for the future to reduce overheating - drive with the rad cap off. You'll have to stop and top up water plain water will do, about every 15-20 minutes, half a gallon at least, but you won't overheat. Does not apply to a situation where the water pump is not running at all.

[jehu]

Does not apply to a situation where the water pump is not running at all.

well that was of course my situation as the belt had been broken. I'll probably be able to get a belt and put that on tomorrow and then I'll be able to see what I have. The one unusual sound I heard was in an effort to circulate some oil to see if there was any evidence of coolant having entered I noticed something like backfiring you know that popping the engine can make when RPMs are falling after revving it.. I suspected that was just because there were no belt creating the usual drag on the crank or the coolant which erupted when I removed the cap had possible gotten into the intake from the rear air intake manifold Crank Case Vent Cover.

[moroza]

The main issue with aluminum heads is when they're mated to iron blocks. You have short heads made of the same material as the block. "Coolant boils = engine junk" is flat out wrong. I've never pegged the gauge but run at 3/4 for a couple of minutes, repeatedly. M60s are pretty resilient regarding heads and headgaskets; I can't recall hearing of a blown gasket on one. You're probably ok.

[jehu]

The main issue with aluminum heads is when they're mated to iron blocks. You have short heads made of the same material as the block. "Coolant boils = engine junk" is flat out wrong. I've never pegged the gauge but run at 3/4 for a couple of minutes, repeatedly. M60s are pretty resilient regarding heads and headgaskets; I can't recall hearing of a blown gasket on one. You're probably ok.

Have you any idea at which point the COOLANT TEMP warning message is triggered? I didn't see the gauge was pinned until after I saw that warning message on the console check control and I shut it down probably withing 20 seconds of seeing that and opened the coolant cap.... I assume that warning gets thrown once the temp has pushed the gauge into the red range so I am sort of a little less panicked if the correlation between the needle and the warning means the danger zone could have only been less than 30 seconds and not the entire three minutes I drove it. Since i didn't see when the needle pinned I feared it could have been longer but if I can learn how the CC reports the temp warning that'd help.

[atl530i]

The main issue with aluminum heads is when they're mated to iron blocks. You have short heads made of the same material as the block. "Coolant boils = engine junk" is flat out wrong. I've never pegged the gauge but run at 3/4 for a couple of minutes, repeatedly. M60s are pretty resilient regarding heads and headgaskets; I can't recall hearing of a blown gasket on one. You're probably ok.

Thinking the same thing. I've seen one blown M60 but that was because the previous owner ran the car with no coolant for a long period of time without stopping and letting the car cool off.

[jehu]

to update this we found the water pimp shaft had substantial play so that was replaced before throwing the belt on. When we started it almost immediately some crazy noise and smoke appeared... it was quickly traced to the Alternator... the case was cracked and the pulley had seized... so after tossing in a brand new Bosh Alternator ... seems the engine is OK... no indication of any detriment from my thoughtlessness.

[401michael]

to update this we found the water pimp shaft had substantial play so that was replaced before throwing the belt on. When we started it almost immediately some crazy noise and smoke appeared... it was quickly traced to the Alternator... the case was cracked and the pulley had seized... so after tossing in a brand new Bosh Alternator ... seems the engine is OK... no indication of any detriment from my thoughtlessness.

glad you got everything fixed. how was replacing your alternator gone about? when I did mine it was relatively easy because I had the radiator support out and could get to it pretty easily. I can only imagine to how one goes about changing it with that cramped space on the driver side. must be a pain in the ass.

[jehu]

So I had it done in a shop owned by a forum member who's probably not all that active in a while but he discussed taking the PS Pump off and dropping it from below while on the lift..Not certain it was necessary to remove the pump but that was what he mentioned doing..

glad you got everything fixed. how was replacing your alternator gone about? when I did mine it was relatively easy because I had the radiator support out and could get to it pretty easily. I can only imagine to how one goes about changing it with that cramped space on the driver side. must be a pain in the ass.