Decarbing an '89 4.3L OMC. Worthwhile?

[Mahoney]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

I say toss the Seafoam, I have read many of Bondo's posts, and he knows what he preaches. I would have never thought to use water, but thinking about how the steam would react in that hot chamber, and seeing that it is kicking out clouds of "crud" seems logical, and boy is it easy. Heck take a pint from the lake on the way back in once in a while and its taken care of.<br /><br />My one question in another post on this topic was; Is is fact or fiction that sometimes that carbon buildup can be beneficial to older engines? Or is it good practice to do it regardless, and it will not hurt anything?

 

[Bondo]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Is is fact or fiction that sometimes that carbon buildup can be beneficial to older engines? Or is it good practice to do it regardless, and it will not hurt anything?<br />

That's Fiction...........<br />Just a few of the Problems that Can be caused by Carbon Buildup,.....<br />Dieseling or Run-on.....<br />Detonation or Spark-Knock...... <br />Stuck Rings + Blow-by....<br />Loss of compression due to Carbon Stuck Valves....<br /><br />And,.. The List Goes On.......<br /><br />IF by chance, that a Problem arises,.... The motor NEEDED Attention AnyWay...........<br /><br />The Key is Pour the Water, Fast enough to cause the engine to Stumble+ Labor,.. But Not Stall......

 

[Mahoney]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Sold, I will be doing this next time I fire it up before taking it out for its first lake run. I am sure it is pretty fouled in there even though it sounds and runs great. <br /><br />It was run for short periods of time during the ignition upgrade and prior to its fuel system clean, it was running very rich due to bad gas and a lot of carbon had a chance to settle its way in the system.

 

[lakelivin]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

I just put in new plugs. I was thinking of cleaning up the old ones a bit & puting em back in before doing the decarb thing, then replacing with the the ones again. Any reason to do this or not?

 

[Bondo]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

I've got a Better Idea........<br /><br />Reinstall the Old Plugs,...... DIRTY.......<br /><br />Then try the Decarbonizing....... Pull the Old Plugs..... You'll "See" the difference........

 

[Mahoney]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Ha. Now I am all anxious to see how well it works, I am assuming the same precausions should be taken with anything around the exaust, as you can prolly expect a lot of sticky black exhaust.

 

[nrladeere]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Actually there is some chemistry involved in the carbon clean up. The carbon and Oxygen present in the combustion chamber are involved in a water shift reaction which create CO and H20 consuming the carbon in a chemical reaction. Very efficient and effective. This is the same process used to decoke large petrochemical furnaces. Chemcial Engineering for boaters!

 

[lakelivin]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Originally posted by Mahoney:<br /> ... Heck take a pint from the lake on the way back in once in a while and its taken care of.

I'm gonna try it, but think I'll stay away from lake water. My lake is pretty healthy, but certainly not crystal clear like some of the deep lakes I was used to when I lived up north. <br /><br />Don't think I like the idea of pouring all those microorganisms into my carb. They might be 'vaporized', but just makes me feel better using 'clean' water, maybe even distilled. Also wonder what would happen to the mineral deposits really hard water contains? Probably irrationally overly cautious, but it's a big enough leap getting myself to pour water down my carb in the first place, lol.

 

[Mahoney]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Well I tried it last night, but I think you should wait till you are running at operating temperature. I also noticed despite how good my engine was sounding, that one of the jets is clogged so I will need to blow that out this evening.<br /><br />Despite that, it was actually amazing how much water an engine can actually process! I was able to pour a pint of water into the carb at about 1500 RPM faster than I could have drank it with hardly any sputter! I will also need to check the plugs tonight and look in the cylinders to see if there is any noticable difference.

 

[Bondo]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

You'll get Much Better results if you follow All 3 Steps.............. <br /><br />Should I go back,+ edit My post,... Putting in the Step #s ??.......

 

[Mahoney]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Naw, Bondo, your instructions were clear, I was just in a hurry. In the drive, my engine runs pretty cool, and takes a good 15 - 20 minutes at fast idle to get up to operating temp. It was starting to get late and I didn't want to bother my neighbors with a V8 engine running in my drive to greet them when they got home from work.<br /><br />Ill try it again when I get the carb blown out.

 

[trog100]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

they say that for every gallon of fuel burnt during the normal combustion process a gallon of water is produced.. so water and the inside of an engine aint entirely strangers..<br /><br />trog100

 

[weatherz]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Not to beat a dead horse with this thread but, Bondo, Any idea what kind of effect doing this would have on oxygen sensors, catalytic convertors, the computers air/fuel settings, etc.?

 

[QC]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Wynter, boats don't have any of that fun stuff in the exhaust . . . yet. If your are talking about a modern car, I wouldn't want to risk blowing the residue and water through a catalyst or at the O2 sensor. Also the computer should return to the correct A/F ratio etc. afterwards if it is an EFI marine engine.

 

[lakelivin]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Tried it the other day with the old plugs but didn't notice too much of a difference after. <br /><br />Bondo: <br />I had the engine at operating temp and uppped the rpm's, but pouring the water at anything more than a trickle would stall it. Stalled once, shot it with some carb cleaner to get it started again, and then finished with the rest of the water.<br /><br />Haven't changed the points on my boat yet this year. Any idea as to whether new points & plugs first might provide 'hotter' combustion and improve the process?

 

[trog100]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

new points and plugs wont provide "hotter combustion" they might help keep things going by providing a better spark thow.. he he<br /><br />to be honest the engine would need to be under load to get your desired hotter combustion conditions.. ever thought of getting a friend to squirt some in while cruising..<br /><br />another method would be to fit a little nipple to the top of your flame arrestor.. fit a pipe to it connected to a sqeezy bottle.. u could give it a dose then on a regular basis..<br /><br />fit a little 12 volt pump and u could do it at the flick of a switch.. he he<br /><br />war emergency power as and when required.. he he <br /><br />trog100

 

[Reel Poor]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

I would stick with the sea-foam. It also cleans intake manifold and cylinder head runners. Water does not. Water cleans only combustion chamber, piston tops and some of the exhaust.<br />This water thing makes me think about something simular; FUEL INJECTOR CLEANER, when used, is not actually cleaning the injectors {although it will cut varnish, but not trash]. Its designed to clean residue that forms in the intake, cylinder head runners and the backside of the intake valves. This build up restricts runner flow volume, i.e. restricts air and fuel flow to cylinders. Fuel injector cleaner cleans this residue so the engine can breath again. Results, better performance, throttle responce, easier starts,ect.<br />This water trick was pretty common practice when they used to put lead in gas. Lead produces a lot of carbon build-up. Not as much problem with unleaded fuels.

 

[rybad]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

I have done both the "water" method, and OMC (Johnson/Evenrude) also make thier own versions of "Engine Tune-Up in a Can". I actually use the OMC one usually twice a season on mine and it makes a difference. The engine runs smoother immediately. The OMC method is the same.. run eng. to op. temp, spray in until the engine actually dies out, then you let it sit for like 3 - 13 hours. Then fire it up and it runs like new..<br /><br />I also have had luck with the straigh water method, but the OMC version actually coat the entire intake system with solvents, and is "supposed" to work better.. it's like $8 a can, and you need a full can for each engine.<br /><br />-Dave

 

[rogerwa]

Re: Decarbing an '89 4.3L OMC. Worthwhile?

Somebody mentioned it earlier but a dose of Berrymans B-12 in the tank once a year will keep your carb nice and clean from any gum buildup.<br /><br />This works especially well in outboard layed up with gas in the carbs. It can sometimes ( although not always and doesn't replace) avoid a carb teardown.<br /><br />Last year my friends late 70's or so Evinrude 70Hp would stumble on take off. I told him I would help him tear down the carbs later, but I put some b-12 in the tank and it stopped stumbling almost right away. He thought I was a genius. His kids now tell him to ask me when something is broken, because they say I can fix anything. It doesn't get any better than that..