To decarbon or not to decarbon ?

Roberthill

Petty Officer 1st Class
Joined
Dec 3, 2012
Messages
317
Finally got a break in the weather took my 1957 35hp out fishing . Had sprayed cylinders with SeaFoam and let it set a couple days . Had a can of CRC marine tune up after engine warmed up started spraying in carburetor ,lots of smoke , after doing several sprays gave it a heavy dose and motor died let it set for about half an hour , started back up crept throttle to wide open , ran great , better than ever .
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,944
Freeing up the rings does make a difference. One the better 2 stroke oils(XD-50 is one) will go a long way in keeping carbon buildup low. I know I going to get feedback that any TCW-3 oil is fine. Well XD-50 isn't TCW-3 certified, neither is XD-100. But both of these oil far exceed the Spec, are marketed by an engine manufacturer and are two of the very few that are designed for DI engines. DI engines are well known for hard carbon issues.
My 98 Ficht with about 50 hrs on it with a TCW-3 oil HEAD.JPG
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Roberthill, assume that you have used CRC Power Tune UP before, right ? we both agree that after product application, OB idles nicely and runs at full throttle much smoother than before.

Jimmbo, imagine how much more carbon build up an OB can collect if it were the old 50:1 mix technology...

Happy Boating
 

Roberthill

Petty Officer 1st Class
Joined
Dec 3, 2012
Messages
317
Sea Rider this is the first time and the first engine that I ever decarboned . I never was made aware of doing this to an engine before now . It runs a lot smoother now both idling and especially wot. I will admit my age , was born 1940 worked on engines since I was 16 but no formal training , only on mine and friends and family cars and boats. I'v learned a lot from this forum which consists of guys like you . THANKS
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,944
Jimmbo, imagine how much more carbon build up an OB can collect if it were the old 50:1 mix technology...Happy Boating

Actually most conventional 2 strokes heads are much cleaner than this, ever with 24:1 and many hours of use. Direct Injection engines have some different characteristics regarding how the fuel is burnt and what kind of carbon forms. They require oils better the TCW-3 to prevent carbon like shown in the pic and prevent it from forming behind the rings. BRP and Mercury both market oils for DI engines. As I said earlier the BRP XD-50 and XD100 oils aren't TCW-3 cert but are much better oils.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Sea Rider this is the first time and the first engine that I ever decarboned . I never was made aware of doing this to an engine before now . It runs a lot smoother now both idling and especially wot. I'v learned a lot from this forum which consists of guys like you . THANKS


Roberthill, Thanks for your kind words, much appreciated, wanted to thank you too for testing CRC Engine Tune Up. Find that too many boaters on this forum likes going per assuming things, word of mouth or plain theory in many boating topics, instead than testing practice results which is the way to go.

I'm a big fan of CRC, apply product overdose each 100 metered worked hours along spark plugs set change. Restores lost agility & smoothness instantly.

CRC Decarbon.JPG

Disassembling carb's silencer each time to apply product is a waste of time, a short cut is to drill a tiny hole same diam of the red cannula in middle silencer. If it's a multicarbed OB, drill a hole for each carb, no need to remove anything, just spray through hole and voil?. Would recommend to seal cannula against base with proper glue, will avoid cannula from popping off when valve is pressed.

Happy Boating
 

alanfox55

Chief Petty Officer
Joined
Nov 17, 2011
Messages
476
I have a 97 Mercury 30 hp that had low hours on it when I purchased it. I also have a 93 Johnson 70 hp that had low hours on a rebuild when purchased but hadn't been run for about 16 years. I used Mercury engine clean in the gas with both of them and for the first couple of starts black stuff would come out of the prop. Afterwords no more black stuff and they started faster,idled and revved better and seemed to smoke less. I now use it in every tank full. I've also read a lot of good reviews on Yamaha Ring Free I think it's called. Yamaha says to use it for regular maintenance. I've used their carb soak with great success so I would expect Ring Free would work as advertised too.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Those canned carbon removers are good if you're a non regular Sea Foam user.. Alan, good to know that have experienced performance difference using those way to go products...

Happy Boating
 
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