Decarbing my I/O?

Stamey

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I was over in the general engine repair forum, where all threads are locked, so I can't post there. Anyway, I saw a post by gss036 from 2003 regarding decarbing outboards with Sea Foam. That post talked of the benefits of decarbing 2-strokes, but also 4-strokes.

What I would like to know, from the more experienced mechanics of I/O's, is if it is a good idea to decarb my Merc 228, or other I/O configuration?
Is it a good idea to set up a separate fuel system to do a few decarbing cycles on my I/O, or would it be better to just regularly put Sea Foam in my fuel tank and just run it?

I also read about letting Sea Foam soak in the cylinders to free up rings. I don't know how good an idea this would be with my V-8, because I imagine the Sea Foam will work it's way down into the oil pan and may cause problems down there. I certainly would like for my rings to seal better though.

What about just dumping Sea foam down the carb, engine running? Would that be beneficial to the rings?

Thanks,
Chris
 

Fordiesel69

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Re: Decarbing my I/O?

Sea foam is over rated. GM top engine cleaner is much better. It works well thru the intake system and allow to sit overnight. Also pull plugs and dump some down each hole. This will loosen the stuff on the piston tops. AutoRX mixed with the engine oil will loosen the ring packs, but will take you two seasons to get results. One season with autorx, the other season with just oil as rinse. On the third season you will see the oil filter begin to pick up the debris the autorx dissolved.

Overall, this is all a waste of time. Keep fresh fuel in it, fresh oil, and go boating.
 

Bt Doctur

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Re: Decarbing my I/O?

You can decarbon the engine by using a high idle and about 12 oz`s of water poured slowly down the carb throat.
 

Fordiesel69

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Re: Decarbing my I/O?

Only after a hot run at 3/4 throttle to raise heat temps. Otherwise not very productive.
 

Don S

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Re: Decarbing my I/O?

Why do you think you need a decarb? It's not a cure all.
 

45Auto

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Re: Decarbing my I/O?

I decarb my I/O's every time I decarb my car.

(I've been driving over 40 years now, never decarbed a car in my life ....... )
 

Fordiesel69

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Re: Decarbing my I/O?

Using a product like autoRX will do a very slow & safe clean of the engine, but quite frankly frequent oil changes are the best. Like every 100 hrs.

Personally after running auto RX on 2 engines I did not notice any difference. Leave it alone and enjoy the water. Do maintain it on schedule and if it makes you sleep better, do it a tad earlier.
 

Bondo

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Re: Decarbing my I/O?

You can decarbon the engine by using a high idle and about 12 oz`s of water poured slowly down the carb throat.

Ayuh,... I agree,...
If I'm gonna tear down a runnin' motor, I'll do that just before I start the tear down...
The combustion chambers will look brand new Clean...

I don't have much faith in, nor have I seen any positive results from Any "Mechanic in a can" products, including Sea-foam...
 

Stamey

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Re: Decarbing my I/O?

I don't know that I need to decarb. As I read the post from gss036 it mentioned the fact that the carbon problems were not because of the 2-stroke oil, but because of fuel additives, and mentioned 4-strokes also, so I wondered if that train of thought would apply to my I/O engine, rather than just outboards.
Just a post that got me thinking and I figured I should ask before I acted on anything.

Thanks,
Chris
 

Don S

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Re: Decarbing my I/O?

If you start blindly doing everything you read on any website for no other reason than "You read it ...." you are in big trouble.
 

singlesupra

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Re: Decarbing my I/O?

Leave the carbon on the pistons, it adds compression :)
jk, but imo if you havnt found a reason to do it, leave it alone
 

Bondo

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Re: Decarbing my I/O?

Ayuh,... Decarbing with water sometimes helps in a dieseling situation...
If, it's being caused by carbon hotspots on the pistons or valves...
 

Stamey

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Re: Decarbing my I/O?

If you start blindly doing everything you read on any website for no other reason than "You read it ...." you are in big trouble.

Hence why I asked before acting.
But I have heard things about Sea Foam before, and thought I'd ask. Maybe it has no place in an I/O situation, only outboards. That's the impression I have now.

Thanks,
Chris
 
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