Heater in wifes car ( 1986 Nissan Sunny Coupe 40k on clock) has been taking a long time to warm up in mornings last few days, tonight she came home and temp gage was near the top and there was water gurgelling sound behind dash/under bonnet. Any help would be appreciated in knowing what could be causing it, thermostat gone ?
cheers
Have you checked the water level recently?
Why would you have a thermostat in a heater matrix? I have never known a car to have that. The thermostat controlling the engine cooling has nothing to do with the heater matrix supply and return pipes if you follow them on a car engine. It is the heater matrix that is blocked. It's possibly the corrosion in the engine breaking away and blocking it. If the water and antifreeze was never changed regularly then that's what happens to older cars, no matter what the mileage. It will cost around £140 to supply and fit. You can try attaching a high pressure water supply to the inlet, then try it on the outlet and watch the brown sludge coming out of the opposite side. It's only a quick fix. Changing a heater matrix usually requires a local vet that knows bout cars unless you can get your body and hands in to unusual positions.
He neither said nor implied it did.
That doesn't fit with the OP's described symptoms. Far more likely the system has lost coolant, either through a leak or failed head gasket. IIRC those engines were known to be prone to failed HGs.
Morse
My guess is the head gasket. It's not exactly unheard of on late 80s Sunnys.
Morse
Thanks for all the info, coolant levels were all fine, i removed the pipes from the matrix heater, backflushed it and drained the whole cooling system(water was VERY brown) re filled everything and took for a test drive for 20 mins, heater got hot within 5 mins, temp gauge stayed where it should be and no gurgelling noise! no idea what the problem was but seams to be ok now cheers for the info
Sounds like an air lock. I would keep an eye on it though- a failed HG will force gas into the cooling system and cause air locks, gurgling and ultimately blow coolant out when the pressure rises enough. You could be lucky and it turns out to be just one of those things, but keep an eye on it for a week or two in case.
Morse
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