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-   -   Coolant leak, or not (https://www.the75andztclub.co.uk/forum/showthread.php?t=98061)

kaiser 10th March 2012 00:19

Quote:

Originally Posted by Roverjoe (Post 946903)
For six months thought I had a coolant leak, always having to top up with water.
Bought the correct coolant (red stuff which you dilute with water) have not had to top up in three months.
Still checking though just in case.:}


There are a couple of issues here.
The "red stuff" is pretty much the same as the green or the blue stuff, and one of the characteristics of that is, that they tend to solidify when drying up, and they can seal very small holes, at least they do on my vehicle, say a weep around a small hose. Or if not actually sealing it, they make it more visible by leaving a white crust (I use the "green" stuff!)

But that would only be noticeable if prior to that you used no antifreeze at all, I would think.

Secondly, some of the leaks you have can be of the "on-off" nature. Examples are the water pumps, which can be erratic, the plastic T-piece which initially starts leaking only during heavy heat soak.

And finally, again assuming you used no antifreeze before, having added some, will increase the boiling temperature of the mixture (and, incidentally also lower the heat transfer capability). This will mean less pressure and less load on the relief valve in the expansion box cap.

You might thus not have solved a leak as such, or you might. :shrug:
Chances are however good, that you also should be looking at replacing your filler cap on the expansion box in the near future.

planenut 17th March 2012 04:47

I really appreciate the replies, and having tried very hard to trace it, I am certain that it is in the area of said inlet manifold - chipsceola ....how long? you must have known what you were looking at. I've had a look at the book tonight and this won't be a quick job for me, there's more than two things to do! Seriously though, I may have to put up with topping up until i've got a good two clear days to attempt it.. Thanks again for your time and replies.

rover54 17th March 2012 05:33

Quote:

Originally Posted by kaiser (Post 946943)
There are a couple of issues here.
The "red stuff" is pretty much the same as the green or the blue stuff, and one of the characteristics of that is, that they tend to solidify when drying up, and they can seal very small holes, at least they do on my vehicle, say a weep around a small hose. Or if not actually sealing it, they make it more visible by leaving a white crust (I use the "green" stuff!)

But that would only be noticeable if prior to that you used no antifreeze at all, I would think.

Secondly, some of the leaks you have can be of the "on-off" nature. Examples are the water pumps, which can be erratic, the plastic T-piece which initially starts leaking only during heavy heat soak.

And finally, again assuming you used no antifreeze before, having added some, will increase the boiling temperature of the mixture (and, incidentally also lower the heat transfer capability). This will mean less pressure and less load on the relief valve in the expansion box cap.

You might thus not have solved a leak as such, or you might. :shrug:
Chances are however good, that you also should be looking at replacing your filler cap on the expansion box in the near future.

Kaiser, your advice about the red stuff being much the same as the blue or green stuff is in my opinion dangerous as it gives the impression that (i) it doesn't matter what type of anti-freeze you use and (ii) that because they are much the same they can be mixed.

The red stuff as you put it is OAT (Organic Acid Technology) antifreeze and is the only type that should be used because of the different metals in post 1999 engine cooling systems, mixing the two types is not recommeded as they can react and cause a jelly like compound that could block the waterways.

SD1too 17th March 2012 08:00

Quote:

Originally Posted by rover54 (Post 952902)
The red stuff as you put it is OAT (Organic Acid Technology) antifreeze and is the only type that should be used ...

I think you'll find that MG Rover themselves say that non-OAT antifreeze can be used provided that the system is fully drained and flushed. My, and other members' research has revealed that the only difference between OAT and non-OAT is the corrosion inhibitors used. They're both ethylene glycol based and ordinary "blue stuff" is perfectly safe in an aluminium engine.

OAT is heavily promoted because "organic" is considered modern, responsible and fashionable, that's all.

Simon.

chipsceola 17th March 2012 08:55

Quote:

Originally Posted by planenut (Post 952895)
I really appreciate the replies, and having tried very hard to trace it, I am certain that it is in the area of said inlet manifold - chipsceola ....how long? you must have known what you were looking at. I've had a look at the book tonight and this won't be a quick job for me, there's more than two things to do! Seriously though, I may have to put up with topping up until i've got a good two clear days to attempt it.. Thanks again for your time and replies.

The Haynes manual says to disconnect battery and drain coolant etc. did disconnect battery but didn't drain coolant so there was some loss when manifold removed, the clock was 90 mins slow when battery re-connected giving a good indication of time job took using standard standard hand tools, that included changing the rocker cover gasket as well. Incidentally not an answer to my leakage, still topping up as before, source of leak remains a mystery for now.
Chips

chrissyboy 17th March 2012 11:08

Quote:

Originally Posted by rover54 (Post 952902)
Kaiser, your advice about the red stuff being much the same as the blue or green stuff is in my opinion dangerous as it gives the impression that (i) it doesn't matter what type of anti-freeze you use and (ii) that because they are much the same they can be mixed.

The red stuff as you put it is OAT (Organic Acid Technology) antifreeze and is the only type that should be used because of the different metals in post 1999 engine cooling systems, mixing the two types is not recommeded as they can react and cause a jelly like compound that could block the waterways.


total rubbish ... any anti freeze can be used as long as the, say red is drained out so no mixing .only diffrence is the life span . . i have always used the blue one but then i change my anti freeze every 2 years just to keep a tip top cooling system .

planenut 17th March 2012 15:46

Thanks again chipsceola, sorry it didn't fix it, but as suggested, it's probably the best and most economical try.

kaiser 17th March 2012 17:27

Quote:

Originally Posted by rover54 (Post 952902)
Kaiser, your advice about the red stuff being much the same as the blue or green stuff is in my opinion dangerous as it gives the impression that (i) it doesn't matter what type of anti-freeze you use and (ii) that because they are much the same they can be mixed.

The red stuff as you put it is OAT (Organic Acid Technology) antifreeze and is the only type that should be used because of the different metals in post 1999 engine cooling systems, mixing the two types is not recommeded as they can react and cause a jelly like compound that could block the waterways.

You are right, it really doesn't matter what antifreeze you use. Yes, and you can mix them. The main difference is that the OAT guys claim their stuff last twice as long. Other claim that the "red stuff" is aggressive and damages the metal, especially if run dry, an alltime risk with these Rover cooling systems.

Claiming that the stuff can't be mixed, is obviously to the advantage of the supplier of the more expensive stuff sold with each Rover, it makes the average owner specify the same, irrespective of cost.

I have the pleasure of owning many cars, some dating back to the mid fifties. Amongst others I have two Rover P4, a 105R and a 105S. Strangely these engine are also aluminium, cast iron (but no plastic!!!). The one is clean as anything, the other not so, so the one has been protected with ethylene glycol, and the other not, most likely been living on a diet of tap water for a number of years. So I can guarantee you, the composition of the modern Rover engines is not "modern" and they will survive quite perfectly on the old green or blue cooling additives. There is no rocket science in that.

And I have heard the "jelly" story before, but I have never seen it confirmed or experienced it. Can, could, might, possibly, perhaps, maybe, sometimes, at times, conceivably, likely etc. does not make it true.

Many of the new "inventions" are not new, not inventions and not worth it. I am far happier with 10 years of experience. 50 years even beats that.

50 years of experience tells me there is nothing wrong with green or blue antifreezes. That is good enough for me.

So make your own mind up. Else, as Wimpy (in Popeye) would say "Let's you and him fight":D

planenut 24th March 2012 17:18

Right, been there, done it today. Had a go at the IMG replacement, and as someone had done this in "one and a quarter hours", thought it may take four hours........ Five Hours! and what a pig. The gasket went in a treat. The bleeding bleed screw is seized and would not budge at all, and so i've had to plonk some water in to try and all works a treat.
obviously I can't tell if i've fixed the leak yet, but now I need advice on how to fill and bleed the system if the bleed screw is done for, and I cannot get the next hose connection off? Help?

chipsceola 24th March 2012 18:45

Didn't need to bleed mine so no time included for that, battery disconnected but coolant not drained, some loss when IMG removed but easily topped up afterwards, heater hot, all systems normal and clock restarted to give time battery off for. Would add that 1st job (rocker box cover gasket) was done before battery lead removed, so that's not included in time taken.
Chips


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