Checks after coolant loss

[Alkers]

Well I split one of my hoses going up a very long steep hill yesterday, I've a temperature warning light fitted which went off so I caught it just as the coolant alarm started to sound. Engine was running for about 2minutes with the temperature light on and 15 seconds as the coolant alarm sounded.
At this point the coolant was leaking all over the road and when I opened the bonnet I could see and smell steam and smoke. Although I think this may have been from the coolant dripping onto hot parts of the engine, I'm concerned I may have damaged the heat / gasket. What checks should I do once I have the hose replaced?

[mikeonb4c]

Curious that the temperature alarm went off before the coolant alarm as i'd expect temp to rise only after coolant was lost, unless perhaps something like coolant boiling occured first. Were the alternator belts ok as (i think) they drive the water pump also? In terms of next move, i know for sure that not all boil ups wreck the gasket/head. I think you have to repair the immediate cause, refill and bleed system, then see if you are getting any coolant loss, steam from exhaust, lumpy starting etc. I'm not a techie though so hopefully others will comment. Good luck and keep up posted.

[Alkers]

Yeah, that worries me also. I should note that the temp warning light is simply rigged to the existing temperature gauge (which I've modified so that it reacts more quickly to changes in temperature) so it may well be that if I had a stock temperature gauge, the coolant alarm would have sounded before the gauge read off the charts.

[mikeonb4c]

Yeah, that worries me also. I should note that the temp warning light is simply rigged to the existing temperature gauge (which I've modified so that it reacts more quickly to changes in temperature) so it may well be that if I had a stock temperature gauge, the coolant alarm would have sounded before the gauge read off the charts.

Yup that could perhaps explain it. Check water pump/belt all ok. Fingers crossed head / gasket not damaged. The other thing thats not clear is whether the coolant came from a leaky hose/rad/pipe or from an eruption out of the header tank from over pressurisation. The latter is more sinister as it may have been cause by a more deep rooted problem (blocked system or faulty head/gasket for example).

[Alkers]

Found the leak, large (almost an inch) long tear in one of the coolant hoses which would have made me think the coolant would have dropped rapidly and then led to overheating but the van was overheating first - possibly due to the monster hill I'd just driven up!

[mikeonb4c]

Found the leak, large (almost an inch) long tear in one of the coolant hoses which would have made me think the coolant would have dropped rapidly and then led to overheating but the van was overheating first - possibly due to the monster hill I'd just driven up!

All makes sense. I wonder if the cooling capacity of your system was exceeded, leading to over- pressuring of the system which blew the aged hose ahead of the header cap relief valve going. If so that might suggest the system is not working efficiently. For example, is the sensor switching on the rad fans when it should, is the thermostat opening promptly, freely, fully, is coolant flowing freely through the radiator(s) matrix, is water pump pumping well etc. All these components are likely to be old and needing testing/overhauling.

[Alkers]

Feedback from the garage was the relay powering the radiator fans had failed. This makes sense to me as going up the steep uphill I would have had a high load on the engine and poor airflow through the rad, resulting in excess heat, resulting in strain on the coolant hoses and leading to my split hose.
No long-term damage although I'm seriously considering replacing all the coolant hoses. Is this overkill or are certain more prone to failure than others?

[mikeonb4c]

Feedback from the garage was the relay powering the radiator fans had failed. This makes sense to me as going up the steep uphill I would have had a high load on the engine and poor airflow through the rad, resulting in excess heat, resulting in strain on the coolant hoses and leading to my split hose.
No long-term damage although I'm seriously considering replacing all the coolant hoses. Is this overkill or are certain more prone to failure than others?

I think i'd get the main components replaced first (rad, thermostat, sensors, relays) along with any bulging or brittle looking hoses. I'd also check the long thin metal pipe to the rear heater as this corrodes and rusts through with age being exposed to the elements.

[Alkers]

Thanks for that. Do people have much faith in the rubber hoses after all these years (1996 van!)?
The stat is a cheap item so I may as well do that at the same time but the radiator is costly and seems to be working fine. Do they develop leaks also?
What other sensors and relays are you referring to?

[mikeonb4c]

Thanks for that. Do people have much faith in the rubber hoses after all these years (1996 van!)?
The stat is a cheap item so I may as well do that at the same time but the radiator is costly and seems to be working fine. Do they develop leaks also?
What other sensors and relays are you referring to?

Mine are 23 years old and from memory only a bulging top hose and the aforementioned corroded metal pipe have been replaced. I rely on fairly regular inspection and the coolant alarm for risk management.

[Merlot man]

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