To decarb or not to decarb in sunny Australia.

peterbo3

Petty Officer 3rd Class
Joined
Mar 8, 2003
Messages
79
Evening all,<br />Living in warm & sunny downtown Brisbane where the mid-winter temp never falls below 45 Deg F, I have watched the posts re decarbing with interest. I run a 75HP Mariner on my plate alloy C/C in water that is always at least 55 Deg F & normally a lot warmer. I have spoken to my Mariner dealer & also to Mercury Australia re the need to add a decarb mix (aerosol or fuel additive) to my engine & have got a BIG no. I see from the posts thst this is a regular PM procedure in the States. Is this a cold weather deal or do boaties in Fl follow this programme too. I have had several O/Bs (Johnno & Merc) & have never done this & the engines did not appear to suffer. I am able to get out on the water every day of the year however. Your thoughts on this would be greatly appreciated taking into account where I live.<br /><br />Regards,<br />Peter.<br /><br />P.S. Let's kick some arse in Bagdhad & let these towelheads know what reality is!!!!<br /><br />P.P.S. My P.S. may be technically out of place but sometimes the message is more important than the medium.
 

peterbo3

Petty Officer 3rd Class
Joined
Mar 8, 2003
Messages
79
Re: To decarb or not to decarb in sunny Australia.

Addition to above post, engine has VRO which seems to function with no problems.<br />Regards,<br />Peter.
 

SpinnerBait_Nut

Honorary Moderator Emeritus
Joined
Aug 25, 2002
Messages
17,651
Re: To decarb or not to decarb in sunny Australia.

peterbo3, I will more than likely catch a bunch of flack for this, but I, like you have never de-carbed in my life.<br /><br />I also run Mariner and Mercury.<br /><br />I have read a lot of posts on this subject.<br /><br />I still don't understand what happens to a motor if you don't do this.<br /><br />At the end of my fishing season, I just make sure that there is no gas left in the engine and to make sure I get the water out of the engine.<br /><br />Cover it up for the winter, which here in Ky. can get quite cold.<br /><br />In March, uncover boat, hook water up to it, squeeze gas ball, hit starter and ready to go.<br />Never no problem.<br /><br />Probably some people will doubt this, but that is their right.<br />All I know is what I do.<br /><br />The only other thing I do is take my batteries out and put them inside when done fishing in fall.
 

peterbo3

Petty Officer 3rd Class
Joined
Mar 8, 2003
Messages
79
Re: To decarb or not to decarb in sunny Australia.

Thanks Spinnerbait,<br />Appreciate your prompt reply. I do not winterize (is that a word?-who cares) apart from putting on a heavier jacket when I go out fishing. Would really appreciate some technical input from O/B mechanics on this one. All my mates in Brisbane are sticking it to me for this post so I need some input for or against. This (decarb) is an unheard of procedure down under so the more feedback the better.<br />Regards,<br />Peter.
 

FlyBoyMark

Ensign
Joined
Apr 14, 2002
Messages
934
Re: To decarb or not to decarb in sunny Australia.

Carbon or coking is a result generaly of lugging the engine or "cooler" combustion chamber temperatures and sometimes jus' too much oil in the gas. This can be exsasserbated by using "cheap" gas and long periods of trolling or idling. On an engine that generaly runs most of the time in "normal" weather and is not lugged(allowed to spool up to operating RPM), carbon buildup is minimal. Better fuels have a very good deterging action. BUT...in the long run At some time in the futre it would be a good idea once a year to do it anyway...it DOES NOT hurt the engine AND definitely cleans it out... :D
 

peterbo3

Petty Officer 3rd Class
Joined
Mar 8, 2003
Messages
79
Re: To decarb or not to decarb in sunny Australia.

Flyboymark,<br />Thanks for your thoughts on this. I have noted your many prior posts & see that you live in warmer climes. My problem is that I have not had any hassles with carbon buildup nor have my mates. I can see that this is a major PM issue in the States because so many experienced techs advocate this procedure. We are both using the same motors so I must ask the obvious. Our unleaded petrol in Australia is 89- 93 Octane. How does this compare to ULP in the States? Boat usage patterns in places like Fl would be similar to Brisbane. I really need some hard facts from people like yourself because I want to get max use from my motor without compromising the inherent build quality.<br />Regards,<br />Peter.<br /><br />P.S. I have not seen Saddam on the street with his gold-plated AK. Only on TV. "Dead Man Talking?!?!"
 

jim dozier

Lieutenant Commander
Joined
Jan 8, 2003
Messages
1,970
Re: To decarb or not to decarb in sunny Australia.

I don't want to start a firestorm of debate, and my experience with this issue is admittedly limited. That said, as with many things there is a kernel of truth and a lot of additional faith tacked on to it. This is often the source of much of our commerce. These products undoubtedly have some utility, and have some beneficial effect, particularly if your compression is down due to a stuck (from carbon and other deposits) ring or if you idle a lot and have a lot of carbon buildup. I used a can of the stuff recently myself "for general principles". But I am continually amazed at the "benefits" people assign to automotive and marine "maintenance" products (Look at the amazing results you can get on the back of the bottles). As Dennis Miller says "I don't want to get off on a rant here" but I used to work in the marketing of pharmaceuticals and I have watched as some of the products we marketed as essential, and drug of choice, are no longer used, because the patent wore off (read less $$). The best pill we ever made far and away was the Placebo (sugar pill).<br /><br />P.S. I live in Florida (USA) and our gas is either 87, 89, or 93 octane unleaded here.
 

FlyBoyMark

Ensign
Joined
Apr 14, 2002
Messages
934
Re: To decarb or not to decarb in sunny Australia.

All of my "outboard" powered boats have been 60 HP or less and I generaly use better gas and use the manufactures brand of oil(good quality TCW-III). In addition I usually run the engines at WOT for periods of time up to 1 hour and my engines are proped to run in the middle of their peak RPM envelope. Rarely do I troll or idle for any extended period of time. Water temperatures where I run are up to 90' in the summer to down to 60' in the winter. My boat(s) are run almost every weekend and some times during the week. Once a year as I said I run the Mercury brand of spray "Engine Tune" through the carbs. I do get some black tarry goop that comes out in small amounts. I am personally more interested in the varnish that may build up on the pistons and rings that may make them stick more than the carbon. Using higher octane only increases carbon build up because of the antiknock additives. The lowest octane your engine can use of the HIGHEST quality gasoline is the route to go. The most important "device" you can put in your fuel system is a large spin-on type fuel-water seperator filter. This will will probably save you a thousand headaches. I use this type on ALL my motors down to 9.9 HP. Running a "rich" engine will carbon and coke up to as will a lean engine fry and scuff the bores, possible detonate and scuff and fry the piston too. Most all of the problems I see here in south Florida are related to salt water use, lack of proper maitainence, cheap gas and cheap oil, water in the gas. Most of the guys that run in fresh water only, usually have no problems other than a blown engine from over reving to make their bass boat go faster. The parts guy at TNT Performance Marine here in Miami attest to this also. His comments are: Improper breakin, poor maitainence, cheap fuel and oil. He sells the parts and hears the reasons why.(TNT is one of the biggest Mercury dealers world wide located on the old "Thunder Boat Row"..)
 
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