Would anyone advise against doing this in a higher mileage - 60k mile original engine? Of course you'd want the benefits of the clean but the seals are all getting older and more prone to cracking etc. I've done this once before at about 54 000 miles and it seemed to be pretty effective on terms of idle, vacuum at idle etc, even built boost noticeably faster but I'm wondering if The process is too stressful for an older miled out engine. I run a simple boost activated a/i system if that has any bearing

 

Yeah, alot of bearing I think. Auxillary injection makes water ingestion redundant. There's no point to it. As I mentioned earlier and as confirmed by Karack, you're already de-carboning everytime you go into boost....along with controlling knock and cooling.

 

I'd like to know the answer this, my FD is at 120k on the original engine (KNOCK ON WOOD!) and this is the first time hearing about steam cleaning.

I get a slightly rough idle during the hotter parts of the year which have gotten better after upgrading my cooling system, but I'm almost possible it's never been steam cleaned.

 

Your location says Japan. 120k kilometers or miles? If miles, nice job! But you're still on borrowed time. Don't change anything that you normally do. LOL. I'm curious to see how much longer you have. Are you 100% sure it's original?


60k is nothing to worry about. Steam it and keep on trucking. It won't hurt anything... only help.

 

Q; do i need to replace my spark plugs after steam cleaning or is not necesary?

 

120,000 kilometers, it's still what I would condier high mileage. I'm about 99% sure it's still the original engine. It's spent most of its life mated to an automatic gearbox and generaly unabused and well maintained.

The part about don't change anything I normally do, that's my original mentality.

 

Change the sparkplugs if they're old (like normal). Steam will clean them a little, too, but if the electrode is worn, they should be replaced.

120k kilometers or 60k miles (give or take) is not a big deal as long as the engine has been maintained and not completely flogged. If your FD has been used like a regular car, the engines can last 100k+ if they've been well looked after.

 

You'll be fine. My fd when I bought it had 63k on it "original engine". I did the steam cleanings twice a year. Engine never had flooding issues ever. I also changed my plugs and fuel filter once a year. My engine finally died at 108k due to me over boosting.

 

I had my first attempt at steam cleaning today. I started out by myself then quickly realized I couldn't control the throttle, check the exhaust, make sure the hose was still submerged. So I enlisted the help of a friend. Is it easier (as far as the throttle is concerned to do one rotor at a time? I had a t connector and did both at a time, but my friend had a hell of a time from keeping it from bogging out and when it would almost bog out the next second it was revving to atleast 6k (I never asked what he revved it to in an attempt to save it, all I can tell you is that it was earsplitting being so close to the engine). Would it be easier to do one rotor at a time? Would that have a less erratic idle? On a side note I did notice 1 hg/in vacuum more than usual.

 

do not do one rotor at a time.

idle will be erratic no matter what.
i never did one rotor before but i heard that doing one rotor at a time is bad.
just deal with the bad idle

when i do steam clean by myself. i run the water line thru my sunroof and i sit in the driver seat so i can do ensure the line stays submerged in the water and control throttle.
having a friend is helpful to have tho.

 

Zman, what a great idea, ill just buy longer vac hose and do it myself. Thank you so much for your input.

 

i did my stock FD yesterday, did one rotor at a time and had no problems controlling idle. what i have noticed its a smoother operation, no more CAT smell, better compression, i would say its worth it and its super cheap.

 

why are people doing one rotor at a time? just hold it somewhere around 3000+rpm and leave it there. its not hard if your using the throttle pedal. do both at the same time. takes less time too

i don't really have any proof that its bad to do one rotor at a time.only that i was told years ago not to do one rotor at a time.
but simple reasoning say that its a bad idea for obvious reasons. imo

heres a start.....think about what you doing when one rotor has smooth power generated and the other one is erratic.

anyone with some testing background on the subject want to chime in?
thanks in advance

 

Yes, 10-month thread bump. My apologies

There has been some discussion recently on RX8Club.com regarding decarb and steam cleaning, and many of the older 8 owners have been rejecting the benefits of decarbing (in all or in part), with largely the same complaint of "I've pulled apart many engines with and without decarbing and I can't see a difference". But no one really had any quantified info on before and after impact. You guys here have plenty of info, but all too frequently it is rejected as being from a different engine, as if carbon removal properties change or the benefit of carbon removal no longer exists for the Renesis

So I did a test using a borescope to get before and after pics: Decarbing - Before and After Rotor Pics - RX8Club.com

I used both seafoam and distilled water to see if there is a difference between the two, and largely, there isn't in small quantities. Seafoam is expensive enough ($12 for 12oz vs $0.89 for 1 gallon of water) that I didn't go to high quantities of seafoam.

I did notice that you guys recommend doing both rotors at once, and in general I would agree with you. However I can only barely keep the Renesis running by submerging the tube in water completely on just 1 rotor. Both rotors would probably kill it completely, and I would prefer not flooding my stalled engine with water... Might have something to do with the side exhaust ports instead of your peripheral? Unknown.

None of this is really news to you all, but I figured that people might be interested in seeing the pics.

These are with only 6oz (admittedly not much, but it's what the 8 guys have been doing in general, so I was looking to see what they are actually doing)





And 1 face of rear rotor after 1 gallon through just it:



Definitely showing carbon removal on a significant scale.

 

I'm curious, how much seafoam do you usually feed through?

I agree that you wouldn't have a problem, it's just 103 times more expensive per unit

 

About 1/3 of the can. Or if its really got a lot of carbon build up the whole can ( depending on size ).

 

Hmm, interesting. I wonder what would cause the difference in what you see vs what I did... Water and seafoam at a half-can level worked pretty much equally. I kept going with water because it's cheap and by the time I finished a gallon, it stripped nearly all caked carbon from the rear rotor, with only caked carbon sections left being close to the seals, and even that was starting to get stripped away.

 

I may have done the steam cleaning wrong but i always have used seafoam. I'm 14 and i kind of have a rotary tune-up place at my house lol. So please don't think i don't know what I'm taking about since I'm younger.

 

Interesting to see this here.

I first got curious about this when I changed a head gasket on a motor that was leaking water jacket to piston. You guessed it, that piston, its valves and combustion chamber were very noticeably cleaner. Attached is a picture, which one do you think had 'coolant injection'?

Next time I saw this process in action I watched my friend (a Master tech for Mercedes Benz) shoot a garden hose full blast into his 1950s MB 190. He started slowly and gradually increased the throttle and water flow to maintain it at around 3000rpm. Eventually he was at full throttle and controlled the engine speed with the the amount of water he was injecting. This was through a carb mind you!

My theory behind this is only a certain amount of the induction charge can be water before it fails to ignite. If you have the engine at full throttle, and you modulating the water content with the idea of keeping the engine at a fixed RPM you are in essence keeping the percentage of the charge at the break even point. Ie there is too much water in the charge for there to be enough power to accelerate the motor, but there is still enough power in the charge to maintain RPM. I can't say from experience if this is at all a good idea with rotaries, but I watched it not break a piston motor.

At first the cloud out the exhaust was black... then after a few minutes it turned gray, and after another few minutes white. He let it go for what felt like 10 minutes while it was blowing white, backed off the throttle and water. Reinstalled the air cleaner, drove it around the block a couple times then changed the oil.

So to address those earlier that said this doesn't work on piston engines. No it actually does, and you can get quite aggressive with it while not hurting things.

 

I would guess that the bigger problem is getting it spread evenly between the cylinders on piston engines, though this largely depends on the design of the LIM and the location of any service ports. Example, if I were to try this on my MSM, it has just 1 service port, and it's in the UIM, above the center two cylinder runners. I'd expect that it would have trouble reaching #1 and #4. Aux injection would work because it keeps it a spray that would get mixed more evenly with the air flow and make it into all 4 cylinders. Ingesting like this doesn't have that benefit.

 

I actually also did a test on a piston engine with water/meth injection.

I have access to a extremely advanced borescopes ($40-50k), I borescoped the engine before running water injection, and after about each gallon of water I ran through the engine. I'll try to dig up those threads.

heres an example before:



after 2 gallons (same cylinder):



Keep in mind, it took me about one tank of gas to run through a gallon of water, so this noticable difference is only a month apart.



Reference threads with more pics:
Before:
A peak inside my motor - Mazdaspeed Forums
after 2 gallons:
-+- Progress of Methanol Injection in cleaning my motor -+- - Mazdaspeed Forums

I run a devils-own water injection system on my Rx7. I'll probably borescope it as well if i get the chance.