Decarbing old engine - safe?

[mkaminski]

I have a 1982 Evinrude 35HP outboard. I acquired the engine almost four years ago. The boat that came with the outboard was in extremely poor shape with maple trees growing in it, yet the engine has been running fine since then despite the neglect.<br /><br />I've read about decarbing extensively on the forums and am well aware of the procedure listed in the FAQs. Is it safe to decarb an almost 25 year old motor, which probably has never been decarbed before? The only reason I ask is because my neighbor, who is a typical "if it aint broke don't fix it" type, says that the carbon build-up becomes part of the engine and the procedure can destroy the pistons since the mixture runs too hot. This sounds a little rediculous to me, but I would rather double check here.<br /><br />My reason for wanting to decarb is to perhaps gain a little more performance and hopefully keep the motor running for years to come. Thanks

 

[ZmOz]

Re: Decarbing old engine - safe?

Extremely safe. What would be unsafe is leaving the carbon as is. Your neighbor doesn't know what he is talking about.

 

[roscoe]

Re: Decarbing old engine - safe?

Do it twice, just to show him.

 

[JasonJ]

Re: Decarbing old engine - safe?

My 36 year motor didn't seem to mind it too much...

 

[timmathis]

Re: Decarbing old engine - safe?

Forget what your neighbor said and decarb that thing. Just make sure it is away from anything that you dont want to get dirty, It is a messy job. Sure you need to do it, You will be happy with the results. <br />Tim

 

[mkaminski]

Re: Decarbing old engine - safe?

I sprayed deep creep through the fogging intake and let it sit for about 45 mins. When I started it up, it smoked a bit, but there was nothing horrendoes about it. I did it two more times and the same. Am I not to expect much smoke from a 35hp outboard?

 

[ZmOz]

Re: Decarbing old engine - safe?

Depends on how dirty it was. The more carbon buildup there is, the more smoke there will be.

 

[jim dozier]

Re: Decarbing old engine - safe?

You must live on the other side of my neighbor. Everything that comes out of my neighbors mouth is automatically suspect. I can't believe some of the things that come out of his mouth. An they are never couched in terms of maybe, he's always definite about his misconceptions. Your neighbor is wrong. He is probably thinking about old car engines and the concept that old dirt and deposits keep the oil from leaking throught the seals, and I'm not sure it even applies there either. If the rings aren't broken yet and there is carbon in the ring grooves getting as much of it out as possible is a good thing.

 

[Dhadley]

Re: Decarbing old engine - safe?

How long has Helpful Neighbor Ned been in the Marine business? I missed that part.....

 

[LubeDude]

Re: Decarbing old engine - safe?

Originally posted by mkaminski:<br /> I sprayed deep creep through the fogging intake and let it sit for about 45 mins. When I started it up, it smoked a bit, but there was nothing horrendoes about it. I did it two more times and the same. Am I not to expect much smoke from a 35hp outboard?

With an engine that old, I would take out the plugs and spray directly into the cylinders, I may even remove the engine and lay it down so I could be sure the spray was able to sit on "TOP" of the cyliders for a period of time like over night. I might even turn the engine over a few times while it was laying there. I dont thing you are actually getting much done with your procedure. Seafoam will work cold, other products dont do a thing unless the engine is warmed up first.