Mazda Rotary Club

General => General Technical => Topic started by: Jake on September 02, 2005, 12:49:21 PM

Title: Carbon buildup
Post by: Jake on September 02, 2005, 12:49:21 PM
Hi Guys,
          Just found this browsing in the internet about carbon buildup on an FD:

If your carbon problem still persists, you can try “steaming” it out. This method seems a little safer than the harsher methods outlined below in the “Carbon Lock” section, but it’s still more direct than just driving your car hard. The basic theory is this:
You take an old windex spray bottle (any old spray bottle will do) and clean it out thoroughly. Fill it with water. Get an assistant to sit in with the car parked, and rev the engine to about 3k. With the top off the air cleaner assembly start spraying the heck out of that bottle. The engine will bog and you’ll be introducing water into the Air/Fuel mix. This water turns to steam inside the combustion chamber and the steam helps lift the carbon and send it out the tailpipe. Many people have reported good results with this method, but it’s still a little vague how much water you need or how long to do it for. Until I get more info and update the article, I say just use an entire bottle or two of water. You hand will hurt from all the squeezing, but hopefully your car will thank you.

Has anyone ever tried this?  Is it a safe and helpful thing to do?  Would it help carbon buildup at all?  I don\'t have any problems with carbin buildup (as far as I know) but just curious.  Cheers

Jake
Title: Carbon buildup
Post by: davegttph1 on September 02, 2005, 12:54:27 PM
probably drown your engine :eek: to be honest I think its the same theory as that 10k boost. I dont think I\'ll be trying it in a hurry
Title: Carbon buildup
Post by: nikp on September 02, 2005, 01:07:11 PM
I have heard reports that there\'s no such thing as Carbon lock problems with rotaries - just a myth. But I have no opinion or hard facts either way!
Title: Carbon buildup
Post by: MillSpeed on September 02, 2005, 01:12:33 PM
Jesus christ, that\'s gotta be a wind-up! Spraying big gobs of water into your engine? Fookin nuts! The only safe way to introduce water into the intake charge is with a proper water injection system, which introduces the water as a super fine mist. I\'ve heard of engines that run WI being torn down and the internals are spotless.
Title: Carbon buildup
Post by: rmagictastic on September 02, 2005, 01:33:32 PM
the theory is good, but.........i would strongly suggest against performing this exercise.

the engine is not designed to recieve large quantities of water.

As mills said, water injection is a different matter, a tempered supply.

The idea being to make the air heavier and denser(colder) and as we all know, cold air=dense air, and the more air = more fuel=more power.

 I am sure that mills will tell you that this needs delicate set up, to provide the exact quantity of water under certain conitions.


N
Title: Carbon buildup
Post by: Donato on September 02, 2005, 01:38:12 PM
Drop two tea bags and some sugar in there too and tell me if you get tea out of the exhaust..?  :)
Title: Carbon buildup
Post by: rmagictastic on September 02, 2005, 01:39:30 PM
Quote from: DonatoDrop two tea bags and some sugar in there too and tell me if you get tea out of the exhaust..?  :)

LOL :)

il have coffee with milk and 2 sugars please.  :cheers
Title: Carbon buildup
Post by: nikp on September 02, 2005, 01:53:52 PM
I prefer mine with brown sugar and cream please! :)
Title: Carbon buildup
Post by: Jake on September 02, 2005, 02:31:24 PM
Cheers guys, thought it sounded a bit dodgy so I thought I\'d ask about it...this forum\'s great  :)  :)  :)
Title: Carbon buildup
Post by: Trevrx on September 02, 2005, 04:24:12 PM
Why is it dodgy? You will only be spraying a fine mist much the same as water injection, just at an earlier stage of induction.
Title: Carbon buildup
Post by: Martiny on September 02, 2005, 04:27:06 PM
I would like to get Carl\'s perspective on this. It sort of sound feasible.
Title: Carbon buildup
Post by: nikp on September 02, 2005, 04:28:47 PM
Well, i\'m not sure i\'d want to send a load a water through a turbo charger spinning at something like 150,000 rpm. I\'m no turbo expert, but a load of water going through a high precision item like a turbo could turn out to be a real problem!
Title: Carbon buildup
Post by: davegttph1 on September 02, 2005, 04:29:19 PM
Trev, a fine mist? at only 3k revs? the idea behind water injection is the water disipitates into the heat from the turbos when on full boost cooling it down.... too much of the water will just drown the engine....
Title: Carbon buildup
Post by: davegttph1 on September 02, 2005, 04:31:16 PM
spraying water INTO the turbo can cause the housing to crack.... hot metal and cold water do not go....
Title: Carbon buildup
Post by: nikp on September 02, 2005, 04:43:29 PM
Quotehot metal and cold water do not go....

Plus there\'s the momentum of the water droplets being flung about at 150,000rpm. Ok, so at idle on a cold car it probably wouldn\'t be so bad, as they won\'t be spinning, or not very fast. But the instructions say do it at 3000rpm (Engine speed) which means the turbos would be spinning.
Title: Carbon buildup
Post by: Jake on September 02, 2005, 07:35:54 PM
It would be great to get Carl\'s or another tuners opinion on this.

When I saw it I wondered how feasible it might be because if it would work it\'d be great for people who were getting carbon buildup.  I\'m just apprehensive about the idea of spraying that much water through the intake tract unless I\'m 100% it wouldn\'t cause any damage to the turbo.  I wouldn\'t have thought it would cause too much damage to the engine as you\'d imagine it\'d be introduced slowly by the time it\'s worked it\'s way through the intake system to the engine, although I\'m just guessing, I could be completely wrong.
Title: Carbon buildup
Post by: FD3SNuttah on September 02, 2005, 09:32:38 PM
this is one of those things that has to be proven i guess. I myself am a little sceptical of this idea for the same reasons others have said in this thread.

Besides i hear that water injestion for an engine is precarious as it is (unless its metered), i wouldnt purposefully do it, especially to a rotor!

why dont you just use some injector cleaner thats supposed to remove carbon deposits.
Title: Carbon buildup
Post by: RobbieRX-7 on September 02, 2005, 09:40:10 PM
i read about this ages ago..it cant be as good as a proper engine cleaning  chemical to clean your engine internals though can it..probly a loada bollocks.
Title: Carbon buildup
Post by: FD3Typer2 on September 02, 2005, 09:40:41 PM
1. How would you know you have carbon buildup in the first place? (And I am not being sarky!)


2. I cleaned rotors from my previous car while it was being rebuilt, and they had to be soaked overnight in carb cleaner and then brushed to remove the carbon. (Although the amount of carbon was excessive as there was a problem with the engine) I seriously wonder how a shot of a cleaner in a running engine could do a good job in such a short time.
Title: Carbon buildup
Post by: FD3SNuttah on September 02, 2005, 10:20:33 PM
the idea is to use it for a while, like every three thousand miles.

THe other way is to blast your car ALL the time, ever notice how race car engines are much cleaner than street ones? its cos they stay on wide open throttle all the time carbon doesnt have a chance to "stick".#

here is a product that can help you out i reckon you should ask them about suitability in a rotor.

http://www.chevron.com/products/prodserv/nafl/auto/content/fueladd.shtm
Title: Carbon buildup
Post by: Jake on September 03, 2005, 10:25:23 AM
I don\'t have any problems with carbon buildup myself.  I\'ve also just put some injector cleaner through the system so it should be fine anyway, just curious mainly.  Apparantly the symptoms of carbon buildup can be the car not running smoothly, loss of power etc. although I\'m just quoting what I\'ve read.