Rydlyme - How Much

jon and michie

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Hi - I am hopefully going to get to the boat this weekend and get the oil cooler, Heat exchanger and Intercooler off.
So my plan is to clean them up when I get back home (let them soak) then rebuild the following weekend.
anyway how much rydlyme do I need ? do you put the cores in a pure mix or is it diluted down ?

Jon
 
IIRC it's a 50-50 mix. I found about 5 litre mixed (10 litre total) was enough not only to pump around an attached system but also leve about 5 litres in the bucket for the pump to scavenge.

My heat exchanger I was quite surprised holds only about 3.5 litre so I think if you buy 5 litre you'll have sufficient reserve stock for the next time you do it.

on another note if you are taking it all apart. i.e. no aluminium bits, all brass inserts. You can use brick cleaner at a tiny fraction of the cost. Just dip it for an hour, rinse very well, then rod. But do rod. Once again even after acid dipping when everything came up clean there was still one or two raw water tubes blocked in each heat exchanger and as I have discovered (Thanks VP) that the raw water flows 4 times across the heat exchanger, blocking just one tube actually represents a significant percentage loss circa 10% of cooling flow. Bit scary that.
 
Thank you BruceK - just so I am not going to get confused why would I need to pump the rydlyme around when the oil cooler - heat exchanger and the intercooler is going to be taken off the engine and taken home - I thought I could just dip them in a bucket of the stuff ?
Jon
 
Thank you Piers - I am planning to remove the oil cooler - heat exhanger and aftercooler off the engine to soak them in a bucket at home.
so am I correct in thinking that I do not need to use a pump?

Jon
 
Thank you BruceK - just so I am not going to get confused why would I need to pump the rydlyme around when the oil cooler - heat exchanger and the intercooler is going to be taken off the engine and taken home - I thought I could just dip them in a bucket of the stuff ?
Jon

Jon
With Rydlym you have the option of pumping it around insitu. From a small bilge pump in a bucket connect it via hose to the to the heat excchanger outlet (or if yours has a slightly different circulation to a KAD42 the hose that leads to the exhaust elbow). Then fit a drainage hose to the oil cooler inlet (or if yours has a slightly different circulation to a KAD42 the hose that leads to the raw water pump) leading back to the bucket and pump.

This is the common way of doing it but as I have found out is not always successful if tubes are thoroughly blocked simply because it cant get there to do its work. Also you cant check the intercooler air passages for cleaning.

Much better to strip and rod. You dont have to put items in a bucket per se to give them a rince in Rydlym or brick acid before rodding. They are a bucket of sorts alread. Just stand them upright and fill. (Note I wouldnt use brick acid instead of rydlym when insitu on the engine, just on the brass cores)

Even when rincing them first in descaler I still found one or two tubes per core blocked. It doesn't sound a lot but due to the nature of the routing across a core it's a sizeable percentage loss. i.e. There may be say ~40 tubes in the heat exchanger but the water passes through it in 4 loops i.e. 10 tubes per loop. If any 2 are blocked thats a 20% reduction in efficiency
 
edit.

remember Rydlyme etc will only dissolve limescale. It wont do squat for any other debris that's caught in the system. be it vegetable, bits of impeller etc
 
Quite a coincidence Piers, as I sit here writing this I have a similar pump setup pushing Rydlyme through my port engine coolers. I’ve been using it for years, and as you know, it really is excellent stuff.

My problem now is finding someone to sell it to me at sensible prices. I phoned Rydlyme earlier today and they were as much help as a chocolate teapot! They gave me the name of a local supplier that no longer seems to exist!
 
I pump it also around the whole sea water circuit. Rydlyme works best when agitated.. and pumping achieves this so works faster. I normally pump for 4 hours.

One thing to note the Cummins aftercooler has cupronickel body and copper fins something when dipped the copper plates the cupronickel as I found out.. so dipping isn't an option for them. Not sure how the Volvo stuff is constructed?

Don't forget to remove the zinc's!

Rydlyme here is about $110aud for 5l so about 55quid I dilute 1:1 for 10l..

Steve
 
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Hi - I am hopefully going to get to the boat this weekend and get the oil cooler, Heat exchanger and Intercooler off.
So my plan is to clean them up when I get back home (let them soak) then rebuild the following weekend.
anyway how much rydlyme do I need ? do you put the cores in a pure mix or is it diluted down ?

Jon

They claim that 1 US gallon will remove approx 2 lbs of limescale. If you can make some questimate of the amount of scale you will know roughly how much Rydlyme you will need. That will be independent of the dilution rate but the more dilute it is the slower it will react.
You will be able to speed the process up if you dilute with hot water , or warm the mixture ( max temp is 80C IIRC).
1:1 is the recommended dilution as already mentioned .
 
Quite a coincidence Piers, as I sit here writing this I have a similar pump setup pushing Rydlyme through my port engine coolers. I’ve been using it for years, and as you know, it really is excellent stuff.

My problem now is finding someone to sell it to me at sensible prices. I phoned Rydlyme earlier today and they were as much help as a chocolate teapot! They gave me the name of a local supplier that no longer seems to exist!

Rico Services. https://www.ricoservices.co.uk/prod...h[cat]=0&search[price_range]=0&search[form]=1

Worth negotiating....
 
I bought an ebay rifle cleaning brush set. Just a few pounds. Use that to rod the tubes out.

I spent enough time in the army dodging the wrath of SM's gunsmiths when bits of 2x4 wads jammed in the rifle barrel to risk some attachment coming off when wedged in the tubes. There is only one entry point. Get something wedged in there and you're in deep. I went for threaded rod 5mm, as if it jams you can unscrew it. I went for 5mm because the inner diameter is 5.5 mm. The threads give a gentle scrape but not enough to wear the tubes. Horses for courses though. I wanted crud out, not a polish.
 
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