Is decarbing needed?

[Bwalker]

I always here people talking about the practice, but in our commercial fleet we have never de carb any of them. The motors are kept for 5-7 years and are ran every single day May-Sept. The last one I tore down because of a leaky gasket was pretty clean with very minimal deposits on the piston dome, no skuffing, had clean piston skirts and ring land areas.<br /> FWIW we use Esso TCW3 oil and 87 octane shell gasoline.<br />I guess the reason I brang this topic up is because I believe the practice does more harm than good if the engine doesnt need it. Running harsh solvents through a motor using a spray de carb like Merc Powertune would certainly remove lubrication off the cylinder walls and bearings. Not to mention all the abrasive carbon that is liberated and allowed to move through the motor.<br /> What do the pros think?

 

[ZmOz]

Re: Is decarbing needed?

It's needed like an oil change in your car...no, you don't HAVE to do it, but your engine will last longer and run better if you do. It is not bad for the motor in any way, decarbing does not use solvents that are any more "harsh" than gasoline. Decarb products also all contain oil.

 

[LubeDude]

Re: Is decarbing needed?

Originally posted by ZmOz:<br /> It's needed like an oil change in your car...no, you don't HAVE to do it, but your engine will last longer and run better if you do. It is not bad for the motor in any way, decarbing does not use solvents that are any more "harsh" than gasoline. Decarb products also all contain oil.

And, not only that, but any carbon that is lostened, will just go out the exhaust and on to your driveway. This is said so you wont do it in your driveway. <br /><br />I think what OZ is trying to say, is that if you didnt change the oil in your car and then traded it off after 50,000 miles or so, it would still be running ok. Its the next person thats going to pay for it. So, if you are happy doing what you are doing, its your call. Having a fleet of engines is a bit different than your own baby.

 

[sergioy]

Re: Is decarbing needed?

I have performed this on a few outboards I aquired and they worked way better afterwards. So I would say yes.

 

[Ron G]

Re: Is decarbing needed?

i just decarbed my 175 2 weeks ago made a world of difference .i say yes

 

[JasonJ]

Re: Is decarbing needed?

The main purpose of decarbing, as I understand it, is to make sure the rings do not get stuck. The carbon causes the rings to stick, which reduces compression, and causes uneven compression from cylinder to cylinder. A more modern outboard run on synthetic or semi synthetic lube is considerably less likely to ever suffer from this problem than a 30 year old motor that lord only knows what has been run through it.<br /><br />Most proponents of decarbing have done it to these old motors that have had a variety of oils used, and the oils used when these outboards were new were of dramatically less quality than the cheapest oil you can get today. Decarbing a 5 year old motor probably doesn't do a lot, but a 35 year old motor goes from a rattling shaking deathtrap to literally a smooth swiss watch after a thorough decarb. Hope that helps...