Heat exchanger cleaning

I

ians

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Hi
Has anybody used or had any experiance with cleaning products such as Rydlyme
for cleaning heat exchange and oil cooler systems.
Been on boatdiesel and there are so many different ways and stuff from vinegar to brick cleaning solutions people have used
Do any of these work, or am I just been a lazy git and should remove the units and have them cleaned professionaly

Ians

engines are Kad 42s
 
Hi,
I have VP AQD40's which have a heat exchang matrix similar to a car radiator rather than a tube stack. These are very difficult to clean but what does work is Caustic Soda solution, preferably warm or even hot if you can achieve it safely, run through from the outlet to the inlet (ie against normal flow) using a circulating pump and a bucket then flush with fresh water. You have to be very carefull not to splash this on yourself of course and rubber gloves, goggles and a charged hose to hand are vital, but with a little thought and planning it can be achieved safely and it works. I believe brick cleaner works as well used in a similar way. If you have a tube stack however it is best to remove it and rod the tubes carefully. if it needs futher cleaning take it to a radiator specialist and they will boil it up in their cleaning tank.
Regards
Eddie
 
The only success I've ever had has been removal.
Tried all the solutions(cleaning products) and the only solution was get em off!

Stripped the blighters off My Ford 140 Turbo and My current green thing.
Take em off renew, the end cap seals while your at it.
When they are off you can physically "see" that they are clean and undamaged.
Pain in the butt I know but at least you can prod the tubes clear etc etc.
Carefull like, so's yer don't damage owt.
As above the end caps condition can be checked.
Blighters for corroding whilst yer not looking.
Get em off Pal !
Volvo Manual said "must be pressure tested" (oil cooler).
Just renewed every rubber bits and "O" rings etc and carefully reasembled.
Been ok for 30 hours so far.
Checked oil pressure switch/sender thingys whilst I was grovelling about the bilges.
Pressure switch all corroded and fell apart in My hands.
Would not have noticed if I had not decided to pull things off.
Bleedin frightening!
Question--What makes you think they need cleaning?
 
Hi Richard
What make me think they need cleaning, well
Last year the temps we creaping up and running hotter than normal, mainly only on WOT, on cruise at 3200/3300 both temps are round 180/185 go to WOT they get up to 200, and a nats cock hair over.
Been through all the other things, post side have replaced the coolant pump (was leaking) b-----d of a job, overhauled seawater pumps, new temp senders, back flushed system, removed CACs and cleaned (were actually like new)
swapped gauges etc, no impellor bits in system.
Engines are suite as a nut, will cruise all day at cruise revs , but it bugs me that they are running hotter so I see there is a problem and its a bit of preventive maintenance.


Ian
 
Richard

Starboard started creeping near end of 2005 season, port mid 06 season.
both temps come up same and drop pretty much same when easing back on throttles


ians
 
Thinks /forums/images/graemlins/confused.gif Fixed a Mates Sabre last Year.
Did the heat exchanger strip jobbie+ changed the thermostats.
Checked em out for operation with the (stick em hot water check) but one was the wrong heat range, if you get My drift.
Can,t be that though, if your engies were ok previously.
Seems like crud could be it!
 
Yep, forgot to say have changed the thermostats, that was the first thing
Have learnt from previous mistakes, try replacing the cheap things first !
lessons learnt from replacing a starter motor, lots of money, nothing wrong with it,
replaced £10 pound solonoid, all working again.
 
Hi Ians,
I've had problems with my cooling system that lead me to having the heat exchangers cleaned.

My engines are quite a bit older (1980), but I wouldn't go down the route of stripping an exchanger again unless it was a last resort. The problem is that they don't go back together once they're old and/or you bust them trying to break them apart (the stack and case are different metals and corrosion gets a hold).

What I discovered was that the fresh-water side of the stack doesn't get too dirty anyhow (it's in a solution of water and anti-freeze), and the raw water side (which does get blocked with calcium and bits of anode) can be rodded out easily enough with the end caps removed (I just use a straightened wire coat-hanger).

I would double-check all of the following before adding cleaning solutions or having them stripped down;

- raw water impellors are within one season of being new, else replace (they lose their flexibility)
- intakes are not resticted (collapsed hoses, blocked hull intakes etc)
- fresh-water pump belts are not loose/slipping
- exhaust bends are not blocked with rust, debris etc
- coolers are rodded through and clear
- thermostats are working correctly

Good luck - cooling problems are no fun ;o(

Cheers,
Paul
 
Know what you mean Paul ref stripping the exchangers.
However the end caps will have to come off to do the rodding bit.
Used a welding rod to clean the barstewards last time!
Brass/ bronze end caps and zincy luminum body+ salty enviroment.
Great combination innit? /forums/images/graemlins/confused.gif
 
One thought, if you have impellor pumps, is the pump chamber 'cam' getting worn, this will reduce the pumping capacity.
 
Eddie - I'm surprised you would use caustic soda to try to dissolve carbonate/bicarbonate/n-carbonate for which acid would be the obvious choice. e.g. de-furring a kettle.
 
Now I can remember using caustic soda to clean out the exhaust pipe on my Yamaha FS1E many many years ago.
This did work, although I was also told after using the caustic soda, pop a bit of petrol in the exhaust then drop a match in, (please note I was very youung back then) this also worked but unfutunetly too much petrol was added and the exhaust did not survive !! I fortunetly did !!

ian
 
Try citric acid, does not attack anything other than the crud left by the sea water, mix it up with hot water and hear/watch it fizz at it eats up the crud. Also great for clearing lime scale in kettles.

And cheap to buy and safe to use.
 
Ah, but the muck in the exhaust pipe is not quite the same as that in the heat exchanger. The former would be more akin to the muck in your oven, where caustic is used for cleaning.
Glad you survived!
 
Have just done the job on my Volvo 40A.Was unable to clean the matrix so took it to local rad specialist who shoved it in his tank over night.Temps were creeping up at around WOT.
Cleaning bought everthing back to normal.Easy job to do and usually you can get away with just new O rings and not have to replace super expensive rubber boots inside each end of heater matrix block.
 
The problem is that I am on rivers and we get mud sucked up into the system, add a bit of heat and you basically end up with a brick growing inside the heat exchanger, hence the Caustic or Hydrochloric acid treatment.
Regards,
Eddie
 
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