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More Rover help - Coolant loss


tbourner

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Following on from my other thread, we picked up the car yesterday, he said he checked all the levels and overfilled the water a bit (which worried me).

Drove it around a bit yesterday, about 30 miles.

This morning I went out to look at another issue, and the expansion tank is empty! I looked on the dipstick and it looks oily rather than like chocolate milkshake :D , expansion tank seems clean as well, no visible puddles on the floor (although it's been hot today), car drives fine and doesn't overheat (so far).

 

Other worry is the switch on the dash for the elec fan - why?!

 

What should I look for? I've topped up with tap water, should I be checking for white smoke on startup?

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Guest andyb

If the HG is compromised it may be through to just a water passage, so you may not experience any water in oil = mayonnaise problems lol

 

The bubbling on shutdown sounds ominous like the coolant system is being over pressurised by the failed HG and the pressure is continually bleeding off. I had a Daihatsu turbo that kept doing this as the head was cracked. It never lost any water and just bubbled on shutdown. Stayed like that until i sold it 3 years later!

 

If you have a drain pipe off the expansion tank, then just put this into a squash bottle or some other container and catch the coolant thats forced out by the over pressure. Then stick it back in again!

 

If the car is driven too far then a lot of the coolant will be blown out and it may start to over heat. That's probably what the fan switch is for. Or maybe the thermoswitch in the rad is shot. Whichever way, make sure you keep an eye on the temp gauge lol

 

Andy

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I think there are 3 pipes from the tank, I'll check but I think they all go somewhere.

There's damp under the passenger carpet, these cars do have problems with drainage from the passenger door though. Would water still escape through a damaged heater matrix if we've left the switch on cold since it was topped up? ie: Does coolant still flow through the matrix and the vent just redirects as required?

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Sorry to hear about this Trev.

 

Undo the oil filler cap on the engine. Is there any mayonnaise on that?

 

One of my metros kept losing its coolant due to a perished seal on the water pump. The pump is not visible without taking the cambelt cover off, but an indication of this is a puddle of water just to the inside of the front driver's roadwheel. Have you checked for puddles in the morning after the car's been standing for several hours having been previously driven?

 

Fill the expansion tank (make sure you use the bleed screws to try and eliminate airlocks: the metro had two bleed screws, not sure about the 100. Still got airlocks though. When does the expansion tank empty? Whilst being driven, or when it's been left to stand for a few hours?

 

The damp footwell is a bit of a concern. If it's been like that for some time, it might not be long until it needs some welding work to get it through an MOT. See if you can lift the carpet to take a look.

 

I don't know why there would be a switch for the electric cooling fan. The fan is usually triggered by a simple wax-based switch mounted on the radiator. When the rad gets too hot, the wax melts IIRC, conducts electricity and completes the circuit that drives the fan. The wax switch is fairly simple and cheap to replace.

 

I'd follow CW's advice. Get it tested, and if its got HGF, try to get your money back. As you bought it from a garage, you should have some kind of redress, even if they didn't offer a warranty.

Edited by stevie_b (see edit history)
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The leading factor up to 2001 was Rover using Nylon dowels instead of metal ones, the cooling system is up to the job but they did relocate the thermostats on later cars. The problem is that the suffer from 'head shuffle' and localised areas of high temperature in an area between an oil way and coolant way which also causes the sealing bead to deteriorate

 

Ib be banging the door of that garage down about it if i was you!

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I don't think it's HGF, there's no mayo or milkshake anywhere to be seen, I think it's been done before so maybe they uprated the dowels too.

 

The coolant loss was due to it boiling away and us not realising, it did it again Sunday evening but went the whole way - steam out the vents and the entire system dumped out the pipe in the bottom of the rad! :( AA man refilled it and checked it over, his diagnosis is the coolant system isn't really up to the job and the fan being wired to a switch is because the guage doesn't ever go above 45%!!!! So I don't know when it's getting too hot so I didn't switch the fan on!!!

 

Phoned garage, it's in there now, he's gonna replace the rad and get the guage working (hopefully), then we can rewire the fan and it should all be gravy.

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You don't need the appearance of mayo for it to be HGF. Correct me if I'm wrong guys, but the head gasket (if it works correctly) keeps the oil away from the coolant where the top half of the engine meets the bottom half, and also keeps the oil and the coolant from leaking out of the engine.

 

If they mix, you'll get "mayo". If the hg is failed such that it leaks one or both of the fluids without mixing them, then you'll get a puddle on the floor.

 

But fingers crossed it's not HGF. The cooling system is capable, as long as the radiator's in good nick. It's important not to let the car overheat, because that can cause the head to warp leading to (you guessed it) HGF.

 

How did all the coolant boil off? Does that mean there's a leak somewhere?

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K series had a metal pipe that runs across the back of the block, under the inlet manifold, from the water pump. They were notorious for rusting through if there wasn't plenty of antifreeze in the system and are a right pig to get at and change.

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That pipe is pretty rusty, but it's not leaking anywhere cos there are no puddles.

 

I think the coolant escaped through the expansion cap, which will also be changed I would think. The rad was in terrible condition, the only reason I thought it'd be alright was because the temp was staying right in the middle all the time - perfect! Except the guage wasn't working properly. :(

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So what's the problem with HGF in my case then? The engine runs fine, produces enough power, there's no oil in the coolant or coolant in the oil, the oil isn't disappearing and the coolant only disappeared when it overheated - so what do I have to worry about?

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So what's the problem with HGF in my case then? The engine runs fine, produces enough power, there's no oil in the coolant or coolant in the oil, the oil isn't disappearing and the coolant only disappeared when it overheated - so what do I have to worry about?

 

No problem, by the sounds of it. I wasn't sure if the car was still losing coolant on a regular basis, hence my reason for posting up the HGF advice. But if the head gasket is keeping the coolant and oil separate, and keeping the oil in the engine and the coolant in the engine, then you don't have much to worry about.

 

Overheating can cause HGF (when the cylinder head expands slightly differently to the bottom end, effectively warping the engine), but I would guess that would be fairly immediate if that was the case. I don't know if you've got the car back yet, but that's something to keep an eye out for over the first few days (by checking the oil and coolant).

Edited by stevie_b (see edit history)
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Ah no I think it just went out somewhere as steam, the first time I didn't know where the second time was a bit more obvious!! Maybe like I said it needs a new cap or maybe I didn't put it on tight enough or something.

 

Hopefully the brief overheat didn't do any damage then.

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