overheat on the highway - is my motor dead

[dahicori]

Hello everyone,

I feel down today. I was at the halfway of a two ours trip when a heater hose came to failure .And as my harness is completly dead, I saw no light flashing out the danger. I could see a lot of steam coming in te car, as I removed the shift gaiter to fix an overdrive wire the day before. But I could not stop safely at this moment. I had to drive for about 8 miles before being able to stop safely. The engine didnt make funny noise and was still working OK when I stopped.

I had the opportunity to drive a 130k D24 and I smoked it. I feel so shameful. The car sat for 10 years and I buy a cruise control, without even bothering to change the stupid hoses. What a dumbass.

My car is at the garage, and the garagist does not want to start the car before I find the original hose. But still, Can I afford myself to dream to ride my volvo again or not? I heard that if the head is not even anymore, the motor is good for junk.

thanks for your sharing your opinions.

[ngoma]

Let's try not to guilt trip ourselves. It's not healthy.

You have been trying to improve and repair your car for some time, to the best of your ability. Most people lack the motivation or interest to do that.

Your recent experience shows the importance of probably the number one advice we give: Maintain and monitor the coolant hoses and monitor the engine temperatures.

Is your engine damaged beyond repair? Depends on several factors:

1. How much coolant was lost?

2. How hard/how long was it run with the coolant below waterpump level?

3. What were the localized temperatures?

You probably can only answer #1. How big was the leak? Oftentimes a pinhole leak can produce visible steam, but takes a while to leak to a dangerous level.

The greenbook gives specs and instructions for measuring cylinder head warpage.

Fix the hose(s) (AND the temperature gauge!), fill with fresh coolant, test the engine. Watch for leaks (oil and/or coolant) at the head gasket, especially in the middle, under the vacuum pump.

You might be able to get away with a cylinder head gasket R/R.

Running excessive overtemps for longer times can cause additional problems, like piston rings losing tension, piston damage, bearing damage, etc.

[dahicori]

thank you ngoma!

I lost almost all the coolant. When I opened up the hood, I could see some in the expansion tank though. , I had to drive a bit less than 10km before stopping the car. well less than 10 minutes for sure. It was a hot day : around 35°

[v8volvo]

Can you post a picture of the damaged hose? Seeing what the failure looks like may help us guess whether the engine could have survived the 10 minutes of driving after the leak began without long term damage.

You could also take the thermostat out and see how much coolant drains from the block when you do that. That would help tell you whether the engine still had some coolant to circulate, or a little, or ran completely dry.

Ultimately, as was stated above, only way to really know what the outcome was is to get coolant back into it once the hose is fixed and see how things go from there. You can do the "bubble test" to check head gasket condition once it's running with coolant in it again. We will cross our fingers for you! :)

A functional temperature gauge -- and an operator who is accustomed to carefully and frequently watching it -- is essential on any engine and all the more so on a D24. You can get away with a lot more neglect under the hood (old hoses, clogged radiators, etc) IF you have the ability to keep eyes on what is going on. Old equipment and no monitoring ability is definitely a recipe for trouble. At least now you know and hopefully if your engine turns out OK, no doubt fixing the temp gauge will be first on your list before using the car again. Some of us have even explored adding warning systems to alert the operator of coolant loss, such as many modern vehicles provide.

[dahicori]

thanks for the positive vibes!!

here is a pic of the damaged hose ( cursed be it!)

https://i.imgur.com/2eYVAT7.jpg

[ngoma]

( cursed be it!)?? :confused:

[dahicori]

I meant "cursed be the hose" but maybe I shouldnt venture to use phrases I remember from highschool !

I will know more about the condition of the motor monday or tuesday. A friend of my father proposed to help me as he has to sell his 740, but it's gasoline powered. Gasoline is 40% more expensive than gasoil here, and all the redblocks look to be prone to high fuel consumption. with my 240, cruising at 90/ 100 km/H is really good for fuel economy. I couldnt tell exactly what was the MPG but it was not shameful.

[ukvolvo]

I meant "cursed be the hose" but maybe I shouldnt venture to use phrases I remember from highschool !

I will know more about the condition of the motor monday or tuesday. A friend of my father proposed to help me as he has to sell his 740, but it's gasoline powered. Gasoline is 40% more expensive than gasoil here, and all the redblocks look to be prone to high fuel consumption. with my 240, cruising at 90/ 100 km/H is really good for fuel economy. I couldnt tell exactly what was the MPG but it was not shameful.

At least you are in france buddy. I have seen all the gates coolant hoses on ebay reduced as old stock on ebay UK. This is a harsh reminder for me to fix our temp gauge too. I check my water and oil every time i drive the car at the moment but without instruments, failures take longer to spot.

Hope she is healthy and there no warping, I have spoken to a man recently who has a d24 cylinder head for sale and a forum member has just acquired a car for spares i know. Im sure one way or another lessons can be learned and well get you going again if you willing to do what it takes.

Remember this engine is a special beast and needs a mechanic who knows how to work on it properly.

Mick

[dahicori]

hahaha , yes , France still is one of the best countries to get a good D24.

You re 100% right, lessons can be learned from every situation.

About having a good mechanic working on the car : the guy who's working at the garage where the car currenty sit told me one minute ago he quit the idea of doing anything on my poor volvo.

He was about to start the car when he noticed smoke getting out of the hood.
doesn't want to see his garage set on fire he said, which I can understand. We're in the middle of august and he has something else to do than trying to help out a guy with is junk car.

Now, I dont want to start an arson. What happened? You know my harness is in very poor condition. Did the steam corrode the wires? What can I do to avoid a fire, clean all the wire, disconnect everything apart from the starter and the pump solenoid?

This is getting complicated :o

But I have to run the HG test....

[ngoma]

He was about to start the car when he noticed smoke getting out of the hood.
Not a good sign...
So he just left it smolder and didn't disconnect the battery? :confused:

Now, I dont want to start an arson. What happened?
Not enough info provided to even make a guess, sorry. :confused:

You know my harness is in very poor condition. Did the steam corrode the wires? What can I do to avoid a fire, clean all the wire...
You will have to investigate further, and if you encounter shorted wiring, then yes you will have to rewire.

...disconnect everything apart from the starter and the pump solenoid?
Don't forget the glowplugs. ;)

[dahicori]

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]

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]

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 :D

have a nice sunday

[ngoma]

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? :confused:

[v8volvo]

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]

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 :confused: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]

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

[dahicori]

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]

Looks like this?https://www.mk1autohaus.com/thumbnail.asp?file=assets/images/068103384a.png&maxx=300&maxy=0

It broke by itself? That is very puzzling. :confused:

[v8volvo]

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. :)

[dahicori]

that is this very bolt indeed :(

And yes that is the case, I set cylinder one to TDC before disassembling the engine. Well that's a good news! I will keep you updated

[dahicori]

So it took a long time !!

But I finally removed the head.

I can see some cracks betweens the valves. but there is no others cracks around.

I am going to check for warpage now.

[dahicori]

https://scontent.fcdg1-1.fna.fbcdn.net/v/t39.30808-6/255502264_10224100595894364_887072081915948617_n.j pg?_nc_cat=109&ccb=1-5&_nc_sid=dbeb18&_nc_ohc=VsZcA-3edNwAX-xIHKF&_nc_ht=scontent.fcdg1-1.fna&oh=c5bbc3201fa86a69200bf9492ccfd7d8&oe=6191CCFD

Hell you all, does this crack look bad to you?

[v8volvo]

Those are the usual cracks that almost all of the old series VW/Audi/Volvo diesels have.

The general rule is that as long as you can't fit your fingernail into it, it is OK. That one looks pretty normal, though you should check it.

Are there any other cracks in other locations, like from a valve seat to a prechamber? Other cracks would be a problem.

And, is the head surface flat or warped? I think that would be another major thing to check after the history on your engine. :)

[dahicori]

thanks for this answer! Well, I can say there is no crack around, the head seems on a visual range but I still did not run the test yet. I bought a 300€ petrol 1.2 twingo (famous french car) to replace the 240 , because I broke. And of course, the HG failed on this one too :rolleyes:
I have to work on the little car before tackling the volvo again...

I do have another question : I think I remember one cannot have a head machined with more than 0.05mm of warpage. But some people told me ...that the machinist can "ignore" the manufacturer's recommandations and flatten the surface anyway. Would you agree? I looked for a second hand head and its simply impossible to find. a brand new head is above what I can afford to have my car back on the road again...