Removing Carbon

T-290

Seaman
Joined
Jul 21, 2001
Messages
56
I'm certain this is not the first time around for a question such as this however I havn't seen any previous posts So here goes, I have a carbon build up problom due to a malfunctioning carb that I am in the process of rebuilding the motor is kicker is a 79" 6 H.P. Evinrude.<br /> The parts man at a local marina suggested spraying a cutting oil( Carb Tuner) that he sold me to clean the carb parts proir to rebuilding through the carb into the running engine! He advised me to be carefull from a standpoint of not clearing out all of the oil that I could seize the motor due to the lack of lubrication from this cutting oil! I have heard of one other method of spraying water into the carb of a running motor! Fact or Fiction to these methods? What's the best solution for removal?
 

DaleT

Chief Petty Officer
Joined
Mar 16, 2002
Messages
469
Re: Removing Carbon

The engine tuner is safer by all the accounts I've heard, not to mention easier. I did it for the first time not to long ago, expect alot of white smoke to come out of the engine. Just follow the directions on the can. The h2o method also works but it sounded a good deal more complicated when I read about how to perform it.
 

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,065
Re: Removing Carbon

The h2o method was used allot on car engines in the late 70's when the emission control systems were installed. I would use the spray tuner available from evinrude.<br /><br />Bob
 

petryshyn

Commander
Joined
Oct 3, 2001
Messages
2,851
Re: Removing Carbon

Ditto ditto<br /><br />It also wouldn't hurt to remove plugs and spray directly into combustion chambers. Pull the engine over a couple times and let sit.
 

T-290

Seaman
Joined
Jul 21, 2001
Messages
56
Re: Removing Carbon

Thanks to all for your acknolwledgement .....T-290
 

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,612
Re: Removing Carbon

I recently removed the cylinder head trying to insure water passages were clear, and cleaned the pistons and the head at that time with carb cleaner and a rag. I sprayed with some lubricating oil before reassembling. I managed to get off a lot of carbon without much difficulty, and didn't seem to create problems. It strikes me that there is less risk this way than loosening up the carbon and then letting the engine blow it out the exhaust -- probably a better cleaning job too.
 

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,065
Re: Removing Carbon

Removing the carbon on top of the pistons is important and it satisfies your view of it being gone. Spraying the cleaner directly into the cylinders from the top is good but the spray MUST also go through the carberators to properly loosen the unseen carbon on the piston rings.<br /><br />Bob
 

Yepblaze

Lieutenant Commander
Joined
Jun 1, 2001
Messages
1,686
Re: Removing Carbon

The carbon buildup on the piston crown and the head area are of less concern than the carbon you may not see between the rings and the ring grooves on the piston. Also in the exhaust ports. I've seen old 16:1 Lawnboys and other two strokes just stop running due to port plugging. It'll usually become evident above idle as more gasses try to exit the chamber. Sometimes a good popsicle stick probing is needed.
 
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