Starting problem

[Tom in France]

A new member posting for the first time. I inherited my father-in-law's 1988 Volvo 240 sedan around 15 years ago. Its 210,000 kilometers have been relatively trouble-free. I replaced the timing belt, water pump and all of the drive belts a year ago at around 208,000 kms (the vehicle is rarely used).
This summer, the top connection on the radiator failed in a spectacular, crumbling mess, as the bakelite plastic disintegrated under the pressure of the hose clamp. I only realized that this had happened because I had stopped to ask a man working in his front yard for directions. He told me that my car had water running out of the motor. Just as I touched the key to turn it off, the motor shut off by itself. Since then, it has refused to start.
I have checked the fuses, changed the fuel relay, and I've changed the main fuel pump and filter. I know that it is getting fuel, as I have disconnected the return fuel line at the injection rail. When I crank the motor, I get fuel out of the line.
I checked the coil, and I have 1.2 Ohms primary resistance and 10,6k Ohms secondary resistance. There is what appears to be a weak spark when I remove a spark plug and ground it against the motor.
I checked the compression in the cylinders. One of the cylinders had only 75lbs. with the three others ranging from 95lbs to 120lbs. I added a teaspoon of motor oil to the cylinder with the lowest compression, and it came up to 100lbs.
I would appreciate any suggestions or advice that the forum members might be able to offer. I hope that I didn't blow the head gasket, but I didn't think to look at the temperature gauge when this happened, and I don't know how to check a blown head gasket, other than looking for foam on the engine oil cap (there is none). When the motor shut off, it was like there had been an electrical problem, as I didn't hear any signs of engine seizure or a mechanical malfunction.
I might also mention that I also checked, when the oil cap was off, and the crank is turning. So, I take that for a sign that the timing belt is still intact.
Thanks in advance for your suggestions.

[honestjoe]

Hi Tom..my old bus is the same age as yours.. and as you have had no response to your plight..i thought i might put my two pence in..you said about a weak spark..I have just replaced the crank position sensor on my bullet proof 88 dl..it never ever let me down.EVER!..but might be worth investigating..best of luck hj.

[Stephen Edwin]

Oh yes I saw this. It really needs input from people far more knowledgeable than me. I have some small thoughts.

A lot of money has been spent already on various parts. How to get a focus on what further work is most likely to help?

When a car suddenly stops and won't re-start there are usually a very few prime suspects. Low cost to moderate cost. I hope that is the case for this car.

When there is, water flowing out, and those compression testing results. This might be rather more than a head gasket.

It might be helpful if the meaning of water flowing out can be established. I find it hard to see that as a literal description by the by-stander.

[Stephen Edwin]

Tom In France.

I think you have been online.

Could you post any clarifying or updating information please?

We might tempt more expert people to contribute?

[Clifford Pope]

It seems obvious that the sudden gush of water was the direct cause of the engine stopping, and a collapsed plastic radiator full of pressurised water would surely fully explain the description of water running out.
(I once had a waterpump seal fail without warning. The temperature rose very rapidly, there were clouds of steam, and the entire coolant poured out in a steaming puddle)

The most common cause of immediate failure to restart after the engine has been sprayed with hot coolant is water in the electrics. Presumably the distributor cap has been dried out.

The worry is that overheating had caused more serious damage, but a sudden collapse of the radiator and loss of coolant while sitting at the side of the road wouldn't do that, suggesting either that the loss had been ongoing and that prolonged overheating had not been noticed, or that there had been some other progressive deterioration, eg poor compression, leaking head gasket, gumming piston rings, etc, and that the water incident was merely the final straw for an already-ailing engine.

I don't see why even an engine with poor compression or a failed head gasket wouldn't make at least some attempt to fire, suggesting something else has failed. When you cleaned and dried the HT wiring, you did put the leads back on the right plugs ?

[Stephen Edwin]

Thank you Clifford.

I tend to think more of steam than gush of water from overheating but I take your point.

As for electrics getting drenched absolutely yes. I remember still when a water pump sprayed coolant to hit the fan. A Morris Minor. Drying out the electrics was quite a task.

And yes an inadvertent swapping of the HT leads or some such thing must be worth checking for.