SCV6 overheated and then catastrophe

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

timc930

Full Access Member
Joined
Nov 13, 2018
Posts
247
Reaction score
103
Location
Mt P SC
Anything is possible and all speculation at this point, but if the HG failed, leaking enough water to cause it to overheat, this could result in the major coolant and oil loss. Unlikely but a possibility. Oil would have to come from internal pressure (coolant pressure into block) to blow oil out.

Another possibility is the shop did not properly secure a hose or other fitting, but then they could of corrected that when you brought it in so they would not have to eat an engine. Sad to think this.

Guessing the HG failed either before, causing the overheat, or after as a result of the the overheat resulting in the oil blowing out. But now would be hard to say if it was cause or result.
 
Last edited:

Joe77

Active Member
Joined
Aug 18, 2021
Posts
41
Reaction score
9
Location
Alberta, Canada
From what I can see it looks like both crossovers are on there.

LR122710 Manifold - heater (I believe this is commonly referred to as a rear crossover)
LR090630 Water inlet tube (I think this would be your front crossover?)

At a glance it looks like they have at least listed all of the correct parts. Maybe one of the super charger guys can confirm that. I have a 5.0L and I think my crossovers are different.

From your description of the failure I would put my money on one of the crossovers. Why they can't find the source of the leak, and their lazy description of what might have happened are red flags to me.

I'm assuming the engine is now seized?
 

greiswig

Full Access Member
Joined
Mar 1, 2021
Posts
550
Reaction score
215
Location
Oregon
I’m trying to remember where the oil cooler is on this engine.

In addition to looking for splits in the plastic on the new crossovers, yes, but I would also be looking for anywhere oil and coolant are together. The head gasket isn’t the only place.

The other thing that strikes me is that you may not want to assume a truly catastrophic failure. It might have started leaking, the wind and fan were blowing everything around under the hood for awhile before you noticed.

And unfortunately, I would not trust the shop that did the work with diagnosing what might well be their own failure.
 

Jakeryan

Member
Joined
Dec 22, 2021
Posts
12
Reaction score
0
Location
Chattanooga TN
This is all excellent info guys. I really appreciate the input and feedback!
I don’t know for certain that the engine is seized. The computer shut it down seconds after the overheat warning came on, and I coasted to the side of the road.
The wind and turbulence in the engine bay could explain how the fluids are where they are. Once stopped with the hood up, I could see the oil on the lower half of the engine and dripping onto the ground all across the front from wheel to wheel. The coolant that I could see was mostly around the overflow tank on the front driver side, and was obviously running/dripping down in that area. I could not see the firewall or back engine bay very well as it was low light and HOT, as well as smoking and steaming pretty badly.

I’m going to walk through the engine bay with the shop tech on Monday and have them show me the exact parts that were replaced so I can see it with my own eyes and get an understanding of how an almost complete coolant system can be replaced/repaired, and yet it didn’t play a part in a subsequent overheating of the engine.
Something that hasn’t been mentioned is the work they did the day before of replacing the plugs and Cyl4 coil. Could this have played a part in overheating? Timing issues?

Thanks everyone!!
 

ktm525

Full Access Member
Joined
Mar 26, 2017
Posts
2,593
Reaction score
1,261
Location
alberta
Typically replacing plugs and coils does not require monkeying with cooling components but perhaps the SC complicates things? Worst case is a new engine and that is likely $15k? If things got that hot it is likely doomed. My old 2010 is mostly doing short trips around town but I do give it a weekly look and sniff to confirm nothing amiss.
 

jlglr4

Full Access Member
Joined
Mar 19, 2019
Posts
932
Reaction score
477
Location
Northern California
I don’t know about the rest of you, but that description of the fluids doesn’t really sound like the typical coolant leak situation. I suppose the reservoir could have failed, or a poorly bled coolant system could have caused the overheating and just boiled coolant out the reservoir. Still doesn’t really explain what sounds like a whole lot of oil across the bottom of the engine.

On the SC model, removing plugs and coils shouldn’t really require disconnecting coolant lines, although the SC coolant lines are maybe a little in the way, so a mechanic might find it easier to disconnect. You could check that invoice to see if they have any charge for coolant.

Wondering if a massive oil leak ran the car dry of oil, car overheated, and the overheating boiled the coolant out the reservoir. Was there coolant left in the reservoir, or was it completely empty? Any heavy knocking sound right before it shut down?

The invoice says they replaced the oil cooler gasket. I’m wondering why that was done in the first place as its not usually work done in connection with this coolant line work. Doubt that repair could have caused this (if the oil cooler was not put back correctly, I think you would have seen oil leaking out right away), but I find it a little curious. FYI, the oil cooler sits right on the block in the valley between the heads. Coolant enters through the back of the water pump, oil enters from passages in the block directly into the cooler from the bottom side.

Trying to think of other places for oil to escape up front. Oil filter assembly, brake vacuum pump, timing chain covers, valve covers, heads, front main seal.
 

Joe77

Active Member
Joined
Aug 18, 2021
Posts
41
Reaction score
9
Location
Alberta, Canada
If you lost oil pressure would there not be warning lights on the dash? From the time you lose oil pressure to the time of engine failure due to overheat should be a couple minutes at least, no?
 

Jakeryan

Member
Joined
Dec 22, 2021
Posts
12
Reaction score
0
Location
Chattanooga TN
Here is the work done the day prior to the incident. Doesn’t say anything about coolant, and nothing was discussed in regards to that.
In the few seconds from the overheating warning to shut down, there were no other warning lights that came up. The engine had some stumbling and I guess you could call it clicking/knocking right before it shut off.

The reservoir bottle had some coolant still in it but wasn’t full by any means.
 

Attachments

  • 97F0B9D3-C32B-402A-8F33-8BCAFF7ABA71.jpeg
    97F0B9D3-C32B-402A-8F33-8BCAFF7ABA71.jpeg
    131.3 KB · Views: 59

greiswig

Full Access Member
Joined
Mar 1, 2021
Posts
550
Reaction score
215
Location
Oregon
I had the same thoughts as @jlglr4 : if it is oil mixed with the coolant, that is not something I’d expect out of a coolant crossover failure. I would double check whether it is oil, transmission fluid (another cooler plumbed into the coolant system) or something else.

It might also be interesting to see what codes got thrown first?
 
Joined
Oct 21, 2020
Posts
16
Reaction score
1
Location
Sidney, Ohio
What a great mystery to work on but not own. The radiator replacement is my wonder. IF it was replaced becaused it leaked or was plugged up (why else) in the past then this engine with high possibility likely overheated. That will do it to check mark head gaskets.
All the other repairs that came were honest and thoughtful.
 

Latest posts

Forum statistics

Threads
36,222
Posts
217,581
Members
30,473
Latest member
OnoA
Top