Dirty/brown/orange colour cooling water

[Merlyn]

Yes, I have sniffed header tanks before, it's certainly not a weekly or even monthly happening but provided the smokemeter is calibrated correctly and it's not a Mickey Mouse one ( looking on the net I see loads of them out there ) you should be able to detect any HC's present in the coolant system.
Provided you keep the smoke head detector clear of the water level ( as it draws a vacuum to suck up its sample ) you should be ok to measure any unburnt fuels present in the coolant.
Where I am at we have two smokemeters which are certified on an every year basis and both have been updated with the latest software as some of the newer engines are hard to measure the smoke output levels.
Their primary use is of course smoke emissions but for example you can measure a smokers reading by his breath output ( just thought I would drop that into the conversation )
The smokers reading will clearly come up on the screen which you can then print.
Haven't yet worked out how to tell which make of cigarette gives what reading so you can tell if the sample supplier is a Woodbine fan or not, never played with that idea as yet.
As your header tank( s) bubble and throw out water on startup I would consider that maybe the sealed coolant system is, to some degree being " pumped up "
As it doesn't continue to do this after running up the offending part might, on heatup of the water expand to seal the offending part(s)
Don't know about the discolouring defect but once again it's being introduced into the system from somewhere.
Again I see it as a diagnostic process eliminating all possibilities until you arrive at the correct answer.
After all the expansion in the header tank is being created from somewhere to bring about the venting.
And bubbles do not come from no-where, they are again being created.
Why it's both engines seems weird, that's why I asked if the same person performed the refit.
Also a pressure test will indicate why the cap lifts to vent ( don't forget the pressure tester can be used to test the cap and see at what psi it lifts.

[1moley]

Here is me making assumptions. Oops! When you said 4/5 gas detector I thought you meant one of those meters you use for confined spaces. Where detecting HC was done by using the LEL function.
My understanding of these meters is all classroom based as the company policy is no crew are allowed to enter a confined space. Shortfalls of doing your cadetship and first 3rds posting with the same company.
From your last post I understand where I went wrong. My father is domestic heating engineer and uses these to test oil boilers. I suspect he won't mind me borrowing said tool for a trip

Interesting point about using the tester to measure smokers breath, My chief smokes more than the engines do. At least 10 with his morning coffee. So it would be amusing to test the smoke level in the ECR at this time.


Your point on 'heatup of water, seals the offending part' is our theory too but we have had all possible offending parts pressure tested and there is no evidence of blowby between gaskets.
We have found why the water level is rising, air is getting trapped in the top hose which is above the venting hose to header tank. If we manually vent the top hose when she is warming up, no bubbles or raising level in header tank. As to how the air is getting into the system is still a mystery.


If we cannot get a smokometer on board in next port of call I suspect the best next step is to send a water sample from each Aux engine ashore to be analysed in lab to help narrow down the search. This would also prove if the dirty water is rust or HC.

thanks,
1moley

[D Winsor]

I know this may be out there but has it been determined that the corrosion is not being generated by electrolysis? Was the alternator overhauled at the same time? If so were the ground straps for the alternator and the engine properly reconnected and any sacrificial anodes in the cooling system replaced?

[Merlyn]

The smokemeter used for checking diesel exhaust emissions would appear to be an entirely different machine as used by heating engineers and as such you could well have a problem here methinks.
However should you be able to obtain a diesel smokemeter there could exist an opportunity for your Chief to participate without his knowledge to assist you in your investigation.
In order to set the machine up for " sniffing " or indeed a smoke test after entering engine details into its brain the machine automatically self calibrates itself by " sniffing " the atmosphere via the sampling tube, if it's not clean air it won't carry on and locks you out.
Then the smokehead internally heats up to 80 degrees and again locks you out until it reaches that figure.
Now these machines have an oil temperature probe which have to be inserted into the oil tank or sump.
So with your little Volvo it's out with the dipstick and in with the probe.
Now this probe has a sliding stop collar which should be aligned with the dipstick rod length to avert the expensive probehead sensor being wrapped around the crank. ( i.e. Project too far into the sump )
Hereby can lie a problem as some engines seem to take for ever to reach temp. so herewith is a " trick of the trade " in case you haven't encountered this problem.
Shouldn't really be done but what the hell, sh t happens.
Sometimes a cold running engine won't attain 80 degrees and you can't go on, the machine has locked you out.
Answer?
Make sure your test coincides with the morning Chiefs Woodbine/coffee break, like the valve / injection timing make sure you get the timing right.
Now I know from past experience a recently boiled cup of coffee wil reach 86 ish but won't stay there for long.
Now, here is a new home for your probe.
You do, however have to apply the love/hate scale at this point concerning the Chief.
In the event of you not being 100% conversant with this scale level one is a bilge rag and level 10 is your spotless pocket hankie.
Their useage?
Which one do you use to clean the dipstick probe of the oil present from your last test with?
Can't help you with this one but be aware the Chief may be reading this so spotless hanky might be order of the day here.
Top secret technology here mind and not to be shared.
Don't forget with our machines at least without the temp. on the screen showing 80 plus you can't even have a header tank sniff jobby.
In conclusion even smoke /sniffer tests need not be boring.
Best of luck with your HC testing.

[1moley]

I know this may be out there but has it been determined that the corrosion is not being generated by electrolysis? Was the alternator overhauled at the same time? If so were the ground straps for the alternator and the engine properly reconnected and any sacrificial anodes in the cooling system replaced?

No it hasn't. We are working off the more likely scenario that the dirty water and bubbles are connected and both engines presented the same symptoms. I will though keep this is mind during the ongoing search.

The alternators had their bearings changed but this was done in situ. As it is completely a FW system there are no sacrificial anodes in the system.

[1moley]

Ah Merlyn. I did have a giggle reading that and yet still very useful information/tutorial. Just like an MOT emission check.
(Anyone not from UK. An MOT is a test all vehicles between 3 and 40 years old must carry out. Essentially checked cars are not dangerous and systems work correctly for the road plus their exhaust emissions are checked)

I do hope I can obtain a smokemeter to carry out this ingenious test of yours. Its for science after all.

[TDC]

Hi,
This is a response I made to someone who had some cooling water issues. Sounds like your case might be different however just in case please see below.

We recently had similar on 2 of our fleet vessels. What we found was that both vessel had replaced rubber expansion joints in the last year. There is a color code for these indicating they are made with different materials depending on the application. The new expansion joints we purchased had a yellow color band and were meant to be used in water systems but there is a red color code for expansion joints to be used with water treatment. We used maxi guard as a treatment and it attacked the rubber in these joints causing black sludge in the coolers and turned the normally pink colored water to cold black.
Hope this helps.
TDC

[Big Pete]

I agree that it has to be something to do with the overhaul and it very much sounds as if exhaust gas is blowing into the cooling water.
You say that the water level goes up when you start the engine, does it go down again when you stop it? This is what you would expect if Gas was leaking in.
If the level stays up, maybe you have fuel or Lube oil leaking in?

BP

[1moley]

TDC

I have read about a very similar issue somewhere else. This may/may not have been your post. We typically use maxiguard as well but due to the colour of the water it is impossible to accuratly add the correct amount of treatment to the system.

I agree that it has to be something to do with the overhaul and it very much sounds as if exhaust gas is blowing into the cooling water.
You say that the water level goes up when you start the engine, does it go down again when you stop it? This is what you would expect if Gas was leaking in.
If the level stays up, maybe you have fuel or Lube oil leaking in?
BP

If on startup and before fully warmed through, you bleed the system. The water level in the header tank does not raise much.
If you do not bleed system. Water level rises and drops to original level once stopped.

[Merlyn]

1 Mosley,
Have you joined up the sniffers club yet?
Been waiting with baited breath here,
Or have you drawn out and bought yourself a million adapter pressure tester kit?
What's the answer?
Don't tell me you have drilled and tapped the top hose and screwed in one of those vent only air bleeders?
Or has someone opened fully the keel coolers valves?
Go on, own up?

[1moley]

Apologies Big Pete, I missed your post before. Water raises/lowers with startup/shutdown.

I hope this will satisfy your curiosity Merlyn and allow you to move back from the edge of your seat

As far as I can find out we do not have a smokemeter on board, so unfortunately I have not had the pleasure. Also we do not have a keel cooling system. We have a HT/LT system with plate coolers.

But I have a curious update!, I rejoined the vessel in the last week and the problems are very much reduced. The dirty water appears very similar to when we paid off.

According to our back to back crew no work was done on auxiliary engines.


Due to the colour of the water it was impossible to judge how much treatment chemical to use in the system before and as we were flushing often we believed it to be a waste. Also around this time we noticed the earth straps on both units were still disconnected and neatly tucked under the plates. We presume some contractor from drydock.

The disconnected earth strap to us would explain the dirty water from corrosion but not huge built up of air when the engine was started and warming up. (Yet once at operating temp system was all okay).

Just before our departure we calculated how much water was in the system and added the appropriate amount of chemical and reconnected the earth straps to both units. We did not notice a change in symptoms.

Rejoining the vessel, water was not as muddy from when we normally rejoin, and after a thorough flushing it is now possible to achieve okay analysis using our testing kit for nitrate ppm The water level does not raise on startup/warmup. We only flushed yesterday but by now the water is usually quite dirty. The photo attached shows current sample and I will try to get find a pic of the old dirty water.
We are still monitoring and are not convinced the above work solved this problem. There is an idea that with all the muddy/dirty water this somehow self-sealed an exhaust gas leak somewhere?

Anyone with an idea of how the above work carried out stopped the introduction of air, only at start/warmup of unit. Please post.
I was wondering if electrolysis was causing the water to break its bonds into oxygen and hydrogen where the oxygen rich environment accelerated the corrosion. But would have thought if this was possible it would continually happen and not at a temperature range of 65 to 70degC. Where running temp is 76 to 78deg.

Many thanks to all for your help, and to D windsor for his idea of checking earth straps.

1Moley.

[Merlyn]

Concerning the now absence of air in the system apon start up without any obvious defects cleared I will stick my neck out here and venture thus;
Someone on board has slipped two bottles of "steel seal " into the header tanks under the cover of darkness into each engine being in the pay of the firm who carried out the repairs.
If the ship has received a visit from the piston/ liner overhaul firm people whilst alongside then this is perhaps more predominant than a James Bond seaborne raid with grappling irons whilst lumping about in the North Sea.
I do know this "Steel Seal " splodge does work because I myself have used it in similar cases to " shut the problem up and make it go away very cheaply and quickly "
As a matter of interest engines with head gasket/cracked heads problems due for replacement and or sale,
Out with the injectors, in with the camera, locate an obvious water leak dripping into the cylinder, back in with injectors ,
in with the splodge ( two plus tins ) start up and off you go.
Soon no more excessive build ups venting from the header tanks and thus no more overheating.
Many hours later out with the leaky cyl. injector, in with the camera and guess what?
No coolant anywhere.
Job done.
Gotta hand it to these modern day sealant boys, seen this repair last for years with no problems.
Just a thought.
We have a saying from the sixties for happenings similar to this in order to shut up deck hands etc. when they used to pump you for reasons as to why.
" It's what we tend to find " and leave it at that.
No point in discussing it further with anyone as behind the scenes we knew no more than them but didn't want anyone to know that.
Still do it today.

( at least I had a go in attempting a conclusion?)

Ps
it's £52 nett a bottle!

[Merlyn]

PPS,

Also had success with that lower O ring.

The liner one that is.