Anyone tried to use a descaler for their heatexchangers?

I treated my port exchanger yesterday.

The process involves pumping "snake oil" through the raw water system at a point beyond the impeller to the exhaust, and circulating the stuff for a few hours.

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Havent yet had a chance to see if any improvements on engine temps but will make sure to report.

curious to hear if others have done this procedure?

I have read many reports of folks using Rydlime to circulate thru their systems. All have reported great results.

I have not tried it. I am stupid and still do mine the old fashion way....taking things apart, rodding them out, etc. Lots of labor but I get to look inside everything and I feel better. Maybe it's the single engine thing...not so bad to do it once.

Twice might*make me feel differently.....

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No No I think we're smart. What does all that stuff do to gaskets, seals, metal ect ect. It's like liquid plumber it would seem. I think it's something that should be done mechanically and by hand. Seems like a relatively easy job that can be done on a rainy day. Is this the same stuff that's put in radiators in cars to get a few more miles from an old one?

I copied the following from a forum several years ago I have never tried it but may do so this summer, Sorry I don't remember the name of the original poster*
Steve W.


Quote Starts
"Ok, I've been refining this process now for a couple of years, and am ready to share it with the forum...
This works for ANY heat exchanger that can be isolated - genset, engine primary, transmission, and your AC system!

You will need:

1. Inexpensive 500gph bilge pump with a 3/4" outlet. 20 feet of 16ga wire and a lighter plug
(or suitable means to connect it to ship's 12V power)
2. About 15' of 3/4" hose.
3. A 5 gallon bucket.
4. 1 gallon of Ph-Ospho-RIC (from Home Depot, found in the paint department - about $13) This is phosphoric acid and a detergent.
5. Chemical resistant gloves and safety goggles are highly recommended.

To clean the H/E:
1. Close the seacock going to the H/E you intend to clean.
2. Remove the hose connections to the H/E. If it is a genset or A/C unit, there is a good chance the connection is 3/4" hose.
If so, you're in like Flynn. Mains will have a larger hose inlet typically; 2" is popular.
3. If the inlet is up to 1", you can get nylon hose-barb adapters at most hardware stores to adapt 3/4" to up to 1".
Buy the ones you need for your specific H/Es once. If the inlet is LARGER (e.g. 2") take one of the
hoses to Home Depot or Lowes and come up with the PVC fittings to make up an adapter; 2" hose, for example, uses a 1-1/2" PVC coupler,
a 1-1/2 to 3/4" threaded adapter, and a 3/4" hose barb to MIP nylon adapter. Fit up the pieces dry in the store and buy what you need.
PVC fittings require PVC cement. Make up the fittings you need to adapt to the hose sizes in question.
4. Connect the output of the bilge pump to the OUTLET of the H/E using the adapter if necessary and half the 3/4" hose.
Take the other half and connect it to the INLET, and run the hose back into the bucket. Place the bilge pump in the bucket.
THE BUCKET MUST BE ABOVE THE H/E YOU ARE CLEANING TO INSURE THAT ALL AIR WILL BE EXPELLED.
5. IMPORTANT: Remove all zincs from their plugs, and reinstall the BARE PLUGS. DO NOT LEAVE THE ZINCS IN THE HEAT EXCHANGER!
5. Add roughly 2.5 gallons of clean water (half full). Turn on the pump and insure that the pump retains prime while circulating the water.
6. Add approximately 1/2 to 3/4 gallon of the Ph-Ospho-Ric to the bucket.

Allow the acid to circulate through the H/E until the foam and bubbling on the surface of the bucket's liquid STOPS.
The amount of time this will require depends on how badly fouled the H/E is; it is not uncommon for this to take an hour or two.
Phosphoric acid will "parkerize" steel and iron along with removing all the rust (a good thing!), and will ignore the cupero-nickel
used in heat exchanger bundles. It will dissolve the organic, mineral and salt deposits, which is what you want.
The solution will turn dark as it works. This is normal.

When the bubbling stops, turn off the pump. Drain the solution back into the source bucket.

Reconnect the original hoses and immediately start the engine or other device, allowing it to run, to flush any remaining residue out of the system.

Make sure to flush the hoses and pump with clean water when you're finished, and reinstall the zincs in the plugs.

You're done."
Quote ends


-- Edited by Steve on Monday 16th of May 2011 07:11:18 PM

This is great. Thanks for posting it Steve.

Ron

this is precisly the process we use. It works great.

I had a 5 degree increase in my operating temperature, that I could not solve by dissassembling and using rods etc.

I then followed the above instructions and 2 hours later, problem solved. I now keep the setup in a box for easy H/E maint.

Last winter I cleaned the HE in situ with white vinegar. Vinegar is very safe and cheap and can be*spilled and mopped up without risk. No messing around with serious acids.

Filled it through a zinc pug and left it for two weeks and then drained. Worked a treat as the engine ran about 5 deg cooler at WOT. It's so easy, I'll do it again this winter.

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Yes, I have used this procedure with Osphoe (phosphoric acid) and it does wonders. I may switch to muriatic acid next time

thanks for posting Steve, the one thing i want to add to the list is the fact that you will not be able to pump it through the water pump with the impeller in place.
i choose to circulate it after the pump, so my entry point was after the pump and before the HE.
if you remove the impeller then you could go through the pump as well. not sure if that makes much difference.

I was going to try muriatic acid in my genset heat exchanger while in place. Diluted it about 4:1 with water. It immediately ate up the gaskets! If you're going to use it, I'd suggest removing it and using a bucket.

the solution i used is from this company:

http://www.maritimeexpressions.com/MEultimatedescaler.html

it is sold in local boat supply stores and well recommended. the liquid appears fairly harmless and according to the labeling it is completely safe.