Area-51 Posted November 10 Posted November 10 Today has been a day of discovery and success while cleaning piston crowns on the 914. After reading MSDS sheets on various you-beaut metal cleaning products off I went to the magic shed cupboard. Pistons from the scrap 912 80hp were used to test some science. One was thrown in a bucket of Selleys sugar soap (oven cleaner), the other in a bucket of nanoic acid (herbicide). After 15 minutes the sugar soap had softened the varnish which could be wiped off with a rag. After 30 minutes more varnish came off with a tooth brush; and after an hour most all varnish was vanquished, and the metal was just beginning to dull a bit. After two hours the piston was stripped fairly clean and the metal had not dulled that much in total. The second piston is still sitting in the nanoic acid at the end of the day without much change at all. Then it was time to clean piston crowns. First a plastic scraper was tried and was all but useless at scraping off carbon. Then a piece of ebony was used, and was all but useless. Then a brass brush was tried which left scratch marks. Then a piece of 1.75mm aluminium sheet was tried. It worked great and left no scratch marks! Then a piece of broken piston skirt was tried and it worked even better, and left no scratch marks because it was the same hardness and material as the piston crown... After nearly 50years I just discovered this today; amazing... With all the wonder of discovery the piston crowns on the 914 all got cleaned as well as they could in the afternoon by first scraping the carbon off with the bit of skirt followed by a 15 minute soak of sugar soap and a flush out with carbi clean and Rostoff, followed by roll over until no more gunk flowed out of the ring lands, then a finishing off of engine oil. The carbon on the top of the bores came off easy after a scrape with the piece of skirt and some light wiping with grey scotch brite soaked in sugar soap. Ready for reassembly... 2 6
facthunter Posted November 10 Posted November 10 No harm with polishing the piston tops.(too late now). It slows the formation of carbon. Soak in Genthin with about equal parts of thin oil with a sealed lid or use a commercial cold bath cleaner for AL. Sugar soap is most likely very alkaline. (Caustic). Nev
Area-51 Posted November 11 Author Posted November 11 Yes, sugar soap is alkaline, sodium carbonate. It rips the carbon deposits off pretty quick. Pulled the test piston out of the acid bucket this morning. It did not clean off the carbon as well as the sugar soap, and did not dull the metal. Below are the test pieces. Right to left, acid 24hr, sugar soap 1hr, sugar soap 2hr. And a couple of pics showing colouration between 24hr acid and 2hr sugar soap.
Area-51 Posted November 11 Author Posted November 11 45 minutes ago, facthunter said: No harm with polishing the piston tops.(too late now). It slows the formation of carbon. Soak in Genthin with about equal parts of thin oil with a sealed lid or use a commercial cold bath cleaner for AL. Sugar soap is most likely very alkaline. (Caustic). Nev The pistons/barrels were not removed; just a decoke sufficient enough on this occasion. Wouldn't do a piston crown polish insitu; too much grit going into the ring lands.
facthunter Posted November 11 Posted November 11 Some rattle can engine cleaners are caustic too.. I don't use it on Aluminium.. In fact I've stopped using it at all. . Kero and hose of is better. Nev
spacesailor Posted November 11 Posted November 11 Some ' car ' makers have their own branded , ' rattle can ' decode cleaner . Tried it on a few engines , without any problems. How many hours to get a decent carbon deposit. ( on my Hummel-Bird ) . spacesailor
facthunter Posted November 11 Posted November 11 Spray in while the engine s running?? I've sprayed water into an extremely TIRED Chev and it cleaned the COKE out. it didn't matter as I'd reco'ed anther ready to drop into it. The rattle cans I'm referring to are for the exterior. of the motor and most of them these days have plenty of alloy.. I would not do it on an AERO Engine EITHER OR a collectible old car or bike. How many hours to get carbon. on the Pistons etc?". Depends on how well it is tuned. Scott bikes I have owned running on modern 2 stroke Oils NO carbon of any note in 1,000's of miles. 2 strokes just after the war would completely block the exhaust port as quickly as 3,000 miles. Nev
spacesailor Posted November 11 Posted November 11 The branded ' decarb ' rattle can , is sprayed into the inlet of a hot engine. My Hummel-Bird only gets half an hour run . Starting on the choke . Being small, it soon gets to it's normal operating temperature. But of course not for long . Three litres of fuel for the monthly run . Makes me wonder if the choke is too much . spacesailor 1
onetrack Posted November 12 Posted November 12 (edited) I bought a Creworks 15L ultrasonic parts cleaner off eBay for under $250, and use a proprietary Ultrasonic Parts Cleaning solution from a local chemical supplier. It all works good, it cleaned up 6 grotty pistons very nicely. The Ultrasonic Parts Cleaner has an inbuilt heater and it goes to 80°C. Despite the UPC solution having a pH of 13, it didn't adversely affect the aluminium. It's watered down to a 1%-5% solution, in use. ULTRASONIC PARTS CLEANING SOLUTION - All Chemical ALLCHEMICAL.COM.AU Buy high-quality ultrasonic parts cleaning solution in australia for various applications. Trusted supplier offering reliable products nationwide. Edited November 12 by onetrack 1
Area-51 Posted November 12 Author Posted November 12 53 minutes ago, onetrack said: I bought a Creworks 15L ultrasonic parts cleaner off eBay for under $250, and use a proprietary Ultrasonic Parts Cleaning solution from a local chemical supplier. It all works good, it cleaned up 6 grotty pistons very nicely. The Ultrasonic Parts Cleaner has an inbuilt heater and it goes to 80°C. Despite the UPC solution having a pH of 13, it didn't adversely affect the aluminium. It's watered down to a 1%-5% solution, in use. ULTRASONIC PARTS CLEANING SOLUTION - All Chemical ALLCHEMICAL.COM.AU Buy high-quality ultrasonic parts cleaning solution in australia for various applications. Trusted supplier offering reliable products nationwide. Yep they are great. Just don't hang around it while its on unless you want to destroy your hearing. Tried jewellers solution at 80c. It cleans steel as new, and starts to dull alloy with more than 30min; and really darkens it if you leave stuff in for 12 or so hours. Have been using dish soap but will still dull the alloy. Tried coca cola without success... straight water or a thin oil works well. 1 1
BrendAn Posted November 12 Posted November 12 On 11/11/2024 at 4:56 PM, facthunter said: Spray in while the engine s running?? I've sprayed water into an extremely TIRED Chev and it cleaned the COKE out. it didn't matter as I'd reco'ed anther ready to drop into it. The rattle cans I'm referring to are for the exterior. of the motor and most of them these days have plenty of alloy.. I would not do it on an AERO Engine EITHER OR a collectible old car or bike. How many hours to get carbon. on the Pistons etc?". Depends on how well it is tuned. Scott bikes I have owned running on modern 2 stroke Oils NO carbon of any note in 1,000's of miles. 2 strokes just after the war would completely block the exhaust port as quickly as 3,000 miles. Nev great stuff
facthunter Posted November 12 Posted November 12 I wouldn't be doing it to anything I own. They also say to change the oil after doing it. I doubt ANY engine manufacturer would recommend it. Nev
T510 Posted November 12 Posted November 12 10 hours ago, onetrack said: I bought a Creworks 15L ultrasonic parts cleaner off eBay for under $250, and use a proprietary Ultrasonic Parts Cleaning solution from a local chemical supplier. It all works good, it cleaned up 6 grotty pistons very nicely. The Ultrasonic Parts Cleaner has an inbuilt heater and it goes to 80°C. Despite the UPC solution having a pH of 13, it didn't adversely affect the aluminium. It's watered down to a 1%-5% solution, in use. ULTRASONIC PARTS CLEANING SOLUTION - All Chemical ALLCHEMICAL.COM.AU Buy high-quality ultrasonic parts cleaning solution in australia for various applications. Trusted supplier offering reliable products nationwide. I use CT14 in my ultrasonic cleaner, does a great job on pretty much anything I have put through it from engine internals to motorcycle crank cases. 1
spacesailor Posted November 12 Posted November 12 (edited) I went to grab a photo of my last " Subaru " can of upper-engine cleaner. But either I hid it too well . Or , the grandies have used it . There is a video on Google. ' Subaru upper-engine cleaner sa459 ' To show the ease of decoding the " boxer " motor . spacesailor Edited November 12 by spacesailor Lost, one number
Area-51 Posted November 13 Author Posted November 13 8 hours ago, BrendAn said: great stuff https://hildstrom.com/projects/2010/01/seafoam/index.html Make your own using diesel naptha and isopropyl... 1
onetrack Posted November 13 Posted November 13 I've used Penrite P26 Foaming Intake Cleaner on a 3.0L diesel PK Ford Ranger, that was suffering from excessive EGR buildup, and showing an EGR fault code. It worked a treat, and the code went off. The engine seems to run better since. Penrite make a petrol version and diesel version, and they recommend you change the oil after using the product. 1
facthunter Posted November 13 Posted November 13 Some of the Subaru's get detonation problems with deposits. and have to be cleaned out with essentially naptha if I recall correctly. EGR build up is a problem when you have engine blowby oily fumes. mixed with soot. Some cars would get so much build up on the under surface of the inlet valves that the port would effectively be blocked 50% by quite hard carbon. No MAGIC solution is going to remedy such conditions. Nev 1
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