overheat on the highway - is my motor dead - Page 2

dahicori · #11 08-10-2021, 02:26 PM

yes sorry for the lack of infos...the guy did not tell me more, he was nervous and unwilling to investigate further. The insurance obliges him to do a diagnosis and he know I will not pay for high cost repairs. So i dont know if the battery was smoking, or the alternator or something else.

he obviously disconnected the battery when he noticed the smoke. I 'll take some wire with me tomorrow and will tell you more about the troubleshooting.

dahicori · #12 08-18-2021, 01:55 PM

So the red wire of the harness that runs inside the car had burned. I removed alternator wirings and started the car. It still has the same sound it used to have since I bought the car, which is quite melodious. But 10 second later, In the area of cylinder six, water started to drip out of the head. Not just a little drop, it was flowing. Near cylinder 4, the HG protrudes from the head! I am going to remove the head, and will check for further damages.

dahicori · #13 08-29-2021, 03:40 AM

hello everyone,

I'm about to tackle the job. I red thorough the technical review. Is there any special tip to succeed on this big operation? Apart from avoiding breaking the threads of te head

have a nice sunday

ngoma · #14 08-30-2021, 11:32 AM

Are you saying you already know how to avoid breaking the bolts when attempting to unscrew them or is that what you are asking advice for?

v8volvo · #15 09-06-2021, 10:46 PM

He might have meant avoiding breaking the injector bosses on the head. Yes that would be a good tip.

Other tips -- work slowly and methodically, take good notes, keep track of what came from where. Otherwise it is simple. The hardest part is resetting the cam and injection timing, and as I recall you have already been through that process before.

We will cross our fingers that everything you see turns out OK. If you saw gross external leakage of water then that probably is not a good sign for the head. You will want to have it checked carefully for warpage. Let us know if you need any help along the way. Good luck!

dahicori · #16 10-05-2021, 12:41 AM

Hello everyone! I ve been off for a while!! I finally tackled the job a week ago. I work VERY slowly.

Yes I was looking for general advice like that.

I was able to set the timing properly then lock the cam with the appropriate tool (the plate). A big surprise came when I removed the hose which is just under the vacuum pump (the nut from above was a real pain in the ass) : maybe 2 liters of coolant came right off. What does that mean

locked thermostat?

I removed sucessfully almost everything but the intake manifold (two screws are now out of shape , I am going to remove them with a ...what's the name in english? We call it "pigtails" in french.

The fuel hose were also a real pain in the ass. I had to break two of them : when I was removing the 17mm nut on the pump, the high pressure outlet fitting of the pump remains totally stuck with the nut So the hose naturally turns with the 17mm nut and I had to cut it. Fortunately, I have some spare hoses.

but my main concern is this head screw, cut off on cylinder 6. I dont have the slightest ideah about how that happened. now, what is your best method for this particular problem? I know I will not have a second chance if I miss one single step. I will wait for sunny and windless day to tackle that one.

many thanks to both of you for following this journey.

Yes the leak was blatantly running though the head. I work pretty hard, and I might buy a new head , too much work for nothing would be heartbreaking

ngoma · #17 10-05-2021, 09:03 AM

Why did you time the engine with a broken head screw?

dahicori · #18 10-05-2021, 12:58 PM

I noticed the screw was broken by chance. I was looking for the size of the tool to unlock to the screws. The oil that surrounds it prevented from noticing the problem at first sight. I then checked thé other screws, no problem

ngoma · #19 10-06-2021, 12:40 PM

Looks like this?

It broke by itself? That is very puzzling.

v8volvo · #20 10-06-2021, 08:22 PM

I think when dahicori said he "set the timing" he maybe means he rotated the engine to #1 TDC in preparation for disassembly? Maybe not that he had timed the engine in the sense of configuring the static timing settings.

I didn't see this myself firsthand, but I heard anecdotally once of a D24T engine that had been seriously overheated, blew the headgasket, and then when the owner went to disassemble it they found several loose headbolts and at least one broken one. Perhaps this can happen due to the aluminum head's expansion when extremely hot that puts extra tension on the headbolts and could cause them to stretch or break.

The good news is if that is the case, the remaining part of the bolt might unscrew easily enough once you get the head removed. It didn't break due to being seized in the block and shearing as you tried to unscrew it -- it broke due to the forces on it during the overheat event. Hopefully the broken off section has a stub sticking up that you can grab with pliers and try to turn. Shoot some penetrating oil down into the threads beforehand too so that if it does start to turn, it will have a good chance of being removed fully.