How was this possible?

mcwhirter

A friend of mine had the belt in the engine snap yesterday. This belt is for the power steering, alternator and water pump.
He was stuck in the north and had no option but to drive it carefully home .
Car still drove for almost 70 miles without all the above operating. The temperature gauge was high but not into the maximum.
The car is a renault megane 1.9 diesel, no turbo.
He got the belt replaced today and the mechanic said the engine is okay, it has done 115k miles.

Surely the engine should have blown?

omb0wyn5ehpij9

That sounds very odd

P.C.

mcwhirter wrote: »

A friend of mine had the belt in the engine snap yesterday. This belt is for the power steering, alternator and water pump.
He was stuck in the north and had no option but to drive it carefully home .
Car still drove for almost 70 miles without all the above operating. The temperature gauge was high but not into the maximum.
The car is a renault megane 1.9 diesel, no turbo.
He got the belt replaced today and the mechanic said the engine is okay, it has done 115k miles.

Surely the engine should have blown?

MMMMMmmmmmmm.

You can drive a car without power steering. It is not fun, but you can do it.
You can drive a diesel without an alternator, as it does not need a spark. You might run out of electricity(for lights, etc), but you can still drive it.
Not so sure about driving too far without a water pump, allthough, it is possible (not sure I would want to do 70 miles).

Drove my Old Man's '81 300D Merc for two weeks without an alternator. The battery died a horrible slow death, and it was a very heavy car to push start.

peasant

No alternator on a diesel is a non-issue once the engine runs

No power steering is a question of muscle

But driving 70 miles without a working water pump and not killing the engine is a bigger miracle than virgin birth

Anan1

There must have been enough circulation through convection to just about keep things cool enough. I wouldn't have tried it myself but, hey, he made it.

DublinDilbert

peasant wrote: »

No alternator on a diesel is a non-issue once the engine runs

Depending on how old the car is or isn't true. On old diesels this is the case, but newer ones would need power for the fuel injectors etc...

peasant wrote: »

But driving 70 miles without a working water pump and not killing the engine is a bigger miracle than virgin birth

It just goes to show how efficient the diesel engine is, and how little heat is being generated as its running...

No way i would drive 70 miles with no water pump.... He mustn't of ever heard of using a pair of tights as a temporary fan belt to just turn the water pump off the crank pulley....

Anan1

DublinDilbert wrote: »

He mustn't of ever heard of using a pair of tights as a temporary fan belt to just turn the water pump off the crank pulley....

Not everyone wears tights, you know.;)

stapeler

If I'm not mistaken the water pump driven by the cam belt.

bbam

peasant wrote: »

No alternator on a diesel is a non-issue once the engine runs

I thought that until...
alternator on my passat died... once the battery was flat the engine wouldn't really run, I presume as the engine managment was dead.. engine went real coarse with no power, kept stalling..

JackFrosty

He had a bit of luck on his side, tell him buy a lottery ticket,

(CH3)2CHOH

As long as he wasn't stuck in traffic and kept it at a reasonable speed then not overheating is quite possible.

I did Limerick to Dublin in a Mk1 Ibiza without the cooling system working at all.

Well when I say Dublin, I mean a cloud of steam just before the Red Cow roundabout.:(

Dartz

I'd say it's well possible.

Diesel engine is pretty efficient, so they dump less heat than a petrol engine. Since some of the heat in a diesel's cycle is used to ignit the next cycle, less of it is wasted to coolant. That's why diesels take time to warm up. I'd well believe only natural convection would've kept that engine cool, especially if he wasn't wringing the neck off it.

DublinDilbert

Dartz wrote: »

I'd say it's well possible.

Diesel engine is pretty efficient, so they dump less heat than a petrol engine. Since some of the heat in a diesel's cycle is used to ignit the next cycle, less of it is wasted to coolant. That's why diesels take time to warm up. I'd well believe only natural convection would've kept that engine cool, especially if he wasn't wringing the neck off it.

I'd tend to agree...

Its not that long ago that some engines were air cooled only...

P.C.

DublinDilbert wrote: »

I'd tend to agree...

Its not that long ago that some engines were air cooled only...

Many years ago, when I did my military service (in Africa), we had a few 10 ton trucks. Some were water cooled, some were air cooled.
The water cooled ones were fine in normal conditions, but when the temp went above 30 degrees, they overheated.
The air cooled ones just kept on going.

Thank goodness I drove an air cooled one. Having said that, I did spend quite a few hours on the side of a dirt road one day cleaning out the diesel filter with about 200mls of petrol. Good thing that I was transporting an outboard engine, and there was a tiny bit of petrol in the tank.

DublinDilbert

P.C. wrote: »

Many years ago, when I did my military service (in Africa), we had a few 10 ton trucks. Some were water cooled, some were air cooled.
The water cooled ones were fine in normal conditions, but when the temp went above 30 degrees, they overheated.
The air cooled ones just kept on going.

Thank goodness I drove an air cooled one. Having said that, I did spend quite a few hours on the side of a dirt road one day cleaning out the diesel filter with about 200mls of petrol. Good thing that I was transporting an outboard engine, and there was a tiny bit of petrol in the tank.

Do you know what the operating temperature range is on air cooled engines?

I presume it must fluctuate depending on ambient temperature, air flow & how much power is being delivered. I guess one major advantage of water cooled is that the thermostat will regulate the temperature.

peasant

You cannot cool a watercooled engine by air alone.

Aircooled engines are constructed with large heatsinks, so that the air actually has something to cool. In addition, there are large fans circulating the air

see Deutz aircooled diesel cylinder here (spot the cooling ribs)
http://www.magirusdeutz.co.uk/images/2stageXSec.jpg

A watercooled engine has a totally different wall setup. The coolant circulates inside the block in small cavities. Once circulation stops (dead water pump) the coolant turns to steam and literally blows the head off and the engine block also gets warped.

Dunno how yer man did it for 70 miles, but driving without a working water pump is generally not recommended

shaywest

once drove from corfu to le harve in a bedford van with no waterpump we drove a bit, stopped a bit, drank a bit, topped up a lot .and drove a bit more .eventually we got home
great days

ianobrien

The old Ford Sidevalve fitted to pre WW2 small fords didn't have a waterpump. It used convection to move the water through the system.

Later sidevalves did however....

Pete67

stapeler wrote: »

If I'm not mistaken the water pump driven by the cam belt.

+1

In this case there would be no issue with cooling, just no power steering or battery charging.

maidhc

peasant wrote: »

Dunno how yer man did it for 70 miles, but driving without a working water pump is generally not recommended

Definately not recommended, but I can easily see how it would be posssible without doing damage, especially on cold days.

samih

Slightly off topic, but it is possible to drive a Ford Zetec SE (like the 1.6 petrol in Focus MK 1 I once had) without any coolant. The engine management will switch off a/c and I think it also shuts down injectors in cyclical fashion to keep things under control. There is a warning light for emergency cooling on dash.

itarumaa

I just dont understand how this is being done,

and no, cold days does not help either. Once my Peugeot 205 decided to brake its waterpump at middle of the winter, it was maybe -20. That car was overheating like a mad after two-three kms.

I think the one reason here was a that car was a diesel, that is the only option I can think about. With petrol engine I would say that thing like this cannot be done, well without damage to the engine anyway.

Darragh29

Are you sure the water pump isn't driven by the timing belt on this car???

mcwhirter

Darragh29 wrote: »

Are you sure the water pump isn't driven by the timing belt on this car???

I asked him, the water pump, power steering and alternator are driven by the belt. The car is a 1998 megane 1.9 diesel with no turbo.
I'm assuming that what saved the engine was that it is the old type maybe, with no frills.