Advice re. GUNGE in MGS's cooling system

[Coalmossian]

I've started 2014 off as I hope it will go on! I'm a wee bit of a "Bah Humbugger" with all this festive stuff, and today I was going stir crazy with the old waiting inside neatly dressed (??) waiting for the grandkids to come out and demolish the place, or for neighbours or whatever! Had M-in-L here for the last week and I am also sick of watching Andre Rieu being lauded to infinity while anyone else with real musical talent is a subject for disdain and a disbelieving headshake!!! If I get like that when I get older ( and I'm only a pre-pubescent sixty four!) I've told my good lady to shoot me!
Anyway, today I went out to join the badger ( but I don't think he/she's actually there just now; must still be out first-footing!) and played with my new toy.

I decided to remove the front bumper/bumper-iron/valance to commence the removal of surface rust and prep for painting. Also removed the chrome strip that surmounts the front panel ( held on by two nice rusty crosshead screws fitted from the FRONT!!!............not a single stud in place!), and thought that I might also remove the front grille panel, front panel and slam panel too to facilitate a little work to clean up some overspray in the engine compartment [frame][/frame]
Next, of course, was hose disconnection and radiator removal. Having been pretty much restored in the recent-ish past, all nuts and bolts are a dawdle to remove, so the Jubilee clips came undone nicely along with the four radiator bolts. Popped in some thin MDF between fan blades and rad. to stop damage to the latter and then pulled the radiator upwards and out! This was what I saw on the thermostat hosing where the hose fitted on! [frame][/frame]
Absolutely choked with a sort of white gunge. It reminded me of lard in appearance and texture but it wasn't greasy! I decided that I'd better go on and remove the thermostat housing and the thermostat.[frame][/frame
Incidentally, not being familiar with the 1098cc engine ( in fact not really being with playing with engines at all as I've been "oot o' the game" for a wee while, I wasn't that impressed with the way the that the metal heater pipe is fastened by two brackets using cylinderhead studs! I don't like having to loosen two cylinder head bolts on the same side in such close proximity in order to move that metal heater pipe to one side to take off the thermostat housing!. I wonder if perhaps the cylinder head bolts should all be tightened down as per normal and then two extra nuts applied to the studs to hold the brackets in place?
Anyway, can anyone suggest the cause of this gunge> It really chokes up the housing and the thermostat so that no water will flow. I presume that I'll just have to scrape it and clean it and replace with a new thermostat after backflushing the system? The actual immediate history of the vehicle is not known otherthan it's a 95% completed restoration and that the engine has supposedly been completely rebuilt, 'though how long it has sat since I really don't know!
AS usual all helpful advice is more than welcome![frame][/frame]
The last photo shows the two components and some of the white gunge. To illustrate my dedication to getting the job done I wanted something of black plastic to put the gunge in so that it would show up well in a photograph. To that end I had to consume a whole, unopened packet of thos rather nice Cadbury's chocolate finger biscuits so I could have the black tray. Now THAT'S dedication to the cause!!!!

[kevin s]

The inside of the water pump and thermostat housing on ours were the same, it seems to be crystals forming from the alloy parts reacting with coolant due to lack of anti freeze / corrosion inhibitor, in our case the water pump and by pass pipes were ruined, I would adise you also check the water pump.

Kevin

[db6431]

Hi
Lovely looking Minor
The gunge is a mixture of oil and water, this can happen if head gaskets fail and coolant mixes with the oil. It can also form on engines that only do short journeys, never getting warm and the water is condensation that forms the sludge with the oil.
I think a good clean is needed, fresh oil and lots of driving

[bmcecosse]

Can oil and water ever mix to form white crystals??? I suspect it is more just hard water residue - I would remove what I could - leave the thermostat out - and try some citric acid in the cooling system - running it up to temperature (blank the radiator) and leave it to react for maybe 48 hours - then drain off. And flush/reverse flush with hose pipe.. You were v lucky to get the thermostat housing off as easily as that! And yes - a check of the water pump condition will be wise. It all rather belays the claim that the engine has been overhauled......

[blues2rock]

I second what BMC says re the origin of the white stuff.
Re your comment about the metal heater pipe being retained inder head stud nuts, those brackets and the engine steady should be on top of the head stub nuts, retained by a second nut.
There are three lengths of head studs, long ones for the rocker posts; medium for the above brackets; and short for everywhere else.
The medium length ones can always be obtained from a mini specialist if the Minor people don't have them.

Good luck with the clean-up.

[Coalmossian]

Can oil and water ever mix to form white crystals??? I suspect it is more just hard water residue - I would remove what I could - leave the thermostat out - and try some citric acid in the cooling system - running it up to temperature (blank the radiator) and leave it to react for maybe 48 hours - then drain off. And flush/reverse flush with hose pipe.. You were v lucky to get the thermostat housing off as easily as that! And yes - a check of the water pump condition will be wise. It all rather belays the claim that the engine has been overhauled......

Firstly, thanks to all for your suggestionsHowever, despite Roy's idea ( and blues2rock seconding it, I don't think it's anything to do with hard water and calcium compound deposits. I well remember hard water from the days of visiting great-aunts and grandparents in my teens, and the formation of that horrible scummy layer in the bath!(Didn't half make you feel embarassed about one's grubbiness!)
Up here in the North East of Scotland we have exceptionally soft water..somewhere around 5.5-6.5 on the pH scale. Do get minute amounts of "scale" in kettles and the like, but generally the acid water slowly eats away at copper water pipes and brass unions, and I know for a fact that this vehicle has spent at least its last two years in this area.
One thing that I have just noticed while cleaning the thermostat housing is that, while being made of alloy like any other I have come across, it isn't an original part as it bears the legends "KMI Sri Lanka" and "No 12" cast into it. So 'tis obviously a repro part. Could it be made of an inferior alloy perhaps which has reacted with water/coolant?[frame][/frame]
On the subject of cooling system flushes and coolant additives with corrosion inhibitors, would members care to make recommendations? What do YOU use, and where is it available?
Thanks again in anticipation

[bmcecosse]

Last two years locally perhaps - but was it running? If you take some of the sludge out - does it dissolve in boiling water? Or kettle descaler , or drain cleaner (caustic soda) or citric acid? Some kitchen experiments are called for! And yes - that part could be made of something 'different' if from Sri Lanka......... Is that the only place where the sludge was found? The heater pipe -yes - longer studs and a top nut - I missed that from the earlier post!

[Coalmossian]

Last two years locally perhaps - but was it running? If you take some of the sludge out - does it dissolve in boiling water? Or kettle descaler , or drain cleaner (caustic soda) or citric acid? Some kitchen experiments are called for! And yes - that part could be made of something 'different' if from Sri Lanka......... Is that the only place where the sludge was found? The heater pipe -yes - longer studs and a top nut - I missed that from the earlier post!

Thanks Roy for your invaluable, and rapid, input.
I've kept some of the white sludge to experiment with, and I'll try citric acid and descaler as well as boiling water. It does seem to partially dissolve in hot water ( about 55-60C). I'll do it tomorrow and let you know.
Presumably you guys are saying to check the water pump as it's made of alloy too?

[bmcecosse]

I would - it's only 4 bolts and a gasket.......

[PaulTubby]

I disagree with the heater pipe mounting saying longer studs and double nuts.... this is not the case, the pipe is fitted direct to the block and held on with the cylinder head nuts and torqued down in order... if you raise the the pipe it will be quarter of a inch higher and bottom hose wont be as good a fit on the pipe.... Your cars pipe was fitted how they was when new.... you could put longer studs and double nuts but do you really need too? how often do you plan removing this ....

here is a photo showing where the pipe goes into bottom hose, if you raise it, it will be to short I feel for a good seal




Also the gunge I feel is just a mixture of it being stood along time and no antifreeze .... this shows in no way that the engine has not been reconditioned... just give it all a good clean and flush and should be ok.. I would remove the water pump and bypass and clean aswell as all hoses.... hopefully heater matrix will be ok and a good flush work...

[bmcecosse]

Longer studs are correct....

[PaulTubby]

.

[bmcecosse]

My 58 car certainly had the longer studs - yes - all 3. It's madness to secure the pipe with head nuts!

[blues2rock]

If using only long and short studs has become commonplace it might account for the surprising number of head gasket failures that have seen reported on this site!

I would not offer an opinion on concours standards as I am no expert on that, but can say that the heater pipe seals perfectly OK when sitting on top of the head nuts.

Either way each to their own - I'll stick with sound engineering practice.

[Coalmossian]

Now boys!! No fighting over the studs issue! I think I might go for the longer ones though!!
Roy, I've done my wee experiment to see what dissolves the gunk! I've used
boiling water ( which, of course, doesn't stay hot for long!)
Mr. Muscle sink and drain unblocker ( caustic soda ),
Citric acid,
Concentrated Hydrochloric acid.
So far it would appear that the two extremes of the pH scale are having the greatest effect, though no exciting bangs or effervescence so far!
I've had a good look at the top hose and shown in the accompanying diagram how much of the gunk is in it.
I've also shown photos of both ends and the contents.[frame][/frame][frame][/frame][frame][/frame].
All that gunk appears to be only in the vicinity of the thermostat housing. There is none below the level of the thermostat.

[blues2rock]

Judging by that last photo I think your minor ate something that disagreed with it.

[Coalmossian]

Blues2rock, Are you suggesting perhaps that when I flush the system out I should use some sort of laxative formula? Any suggestions as to the offending "meal"?
As for my wee experiment;[frame][/frame]
The gunge seemed largely unaffected by boiling water, but then the water cooled very quickly. I could have pursued this further but didn't really think that suggesting boiling some up in one of my good lady's pans would really meet with instant approval!!! Absolutely no sense of adventure, some people!
Citic acid did nothing noticeable.
Both the concentrated hydrochloric acid and the Mr. Muscle sink and drain unblocker did the trick and dissolved the gunge with the former giving a yellowy coloured solution and the latter giving more of an orangey solution. Sadly I have no pH paper here to find out if the gunge is itself acidic or alkaline.
Having done this, the results tell me...................not a lot, really!
Any PhD chemists in the house?
I do think, however, that the alloy is playing a major role in this, possibly aided and abetted by periods of time sitting idle!

[bmcecosse]

Trouble is - conc HCl is not going to do the rest of the engine any good....... I had hoped the Citric may do the job - we sometimes use it dissolve gunge in steam boilers..... Is the gunge ONLY in the 'stat housing - or throughout the block? have you pulled the water pump yet?

[blues2rock]

6 pints of Guiness might do the trick - always works for me.

On a serious note, could the gunge be a consequence of mixing different types of antifreeze? Or perhaps a reaction to something else that has been added to the cooling system?

[Coalmossian]

Roy, Gunge does seem localised to thermostat housing. None below thermostat seating on the head and, as shown in hose photos, plenty at the thermostat end tailing off as you get closer to the radiator connection.
Haven't pulled water pump yet but plan to tomorrow.
I agree that conc HCL circulating around my block is NOT a good idea!!
And, Blues2rock, what a waste of Guiness!! I seem to remember some ales from when I was a lad down in Lancashire. Massey's?? The would be much more suitable.....watery and not a lot of flavour!