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-   -   how often should I redline for carbon removal? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/how-often-should-i-redline-carbon-removal-60608/)

sonic7 04-08-03 02:35 PM

I think ill just stick to the ATF trick.... proven effective

My88Se 04-08-03 03:38 PM

very interesting..someone should try it....just not me. Although the nxt time someone's motor blows this may be a last ditch effort. eh?

White_FC 04-08-03 09:16 PM

I'm betting it would be doing the same thing, or close to the same, as injecting straight water into it.

$150FC 04-08-03 09:41 PM

the difference, i thought, was that the ethyl whatever stuff was poured in while the car was running. usually the ATF trick is done when the car is off, so the ATF has time to hit the oil seals.

nillahcaz 04-09-03 01:24 AM

coolant has a lube in it for the water pump. the crap in coolant "can" make it an acid that is one of the reasons to flush and fill the system. it would take days to make your shoe gummy, and if it eats your shoe it would be grippy not slipperier.

Jimmy325i 04-09-03 01:41 AM

Coolant is the only substance in your cooling system that lubricates the water pump. It is not harmful to rubber and the lubricating properties of it (have you never felt the stuff? it's pretty damn slippery) is what prevented the tires from gripping and thus making the most smoke for sean. Bleach has been used for the same effect in the past. (it's also pretty slippery stuff)

Amur, You need to come up with something someone else has published to back up your little analogies. What if the day before using the WWF container for coolant the guy used it for sulfuric acid? Maybe he also used that thing for circle jerks? Anyone who doesn't properly clean containers of contaminants isn't my idea of a smart person or a good mechanic.

Coolant hoses are not specially treated or formulated for use with ethlene glycol. The idea is rediculous!

hypntyz7 04-09-03 11:01 AM

Personally Im a fan of redlining any car I drive (that isnt being broken in from a rebuild or just had a used engine installed that week) once per driving session, be that once per day, once per week, or 5 times a day.

Now, about this maintenance debate. I am personally a fan of water injection. Not the type turbo guys run to keep intake temps down, but the type you do in your driveway as a maintenance procedure. Find a vacuum line or lines (teed together) that feed both the front and rear rotors, grab the throttle and rev the engine up to 4k or so, and dip the hose in a jug of water and let it drink. The water gets pulled in, hits the rotors and turns to steam, and takes carbon (slowly) with it.

If you're starting with an original/old used engine, Id do this 3-4 times weekly for about a month to clean as much as you can out. I'd also do 2-3 gallons per treatment. From then on, once per month. IF Im maintaining a rebuilt engine, I do this once per month or once per thousand miles to keep everything clean inside.

I have torn down engines where I had previously done this treatment, and they are always very clean, if not carbon-less altogether. The water treatment, along with straight premix, would result most likely in a rotary engine that lasted over 200k miles as the rule, rather than the exception.

As for antifreeze, I have not heard of using that as a maintenance item. I suppose it would have similar effects as the water treatment. I do concur that mazda used to use it for cold climate startups, since I remove the damned bottle on half the engine swaps I do (it aint that cold in the south). For that reason alone, I will theorize that antifreeze would not be harmful to engine internals when used for a short period of time, after all mazda did many years and several million dollars worth of R & D on this engine, I cant imagine they'd make it a policy to inject a harmful ingredient to their engine.

allenbillings 04-09-03 06:21 PM

Ethylene Glycol
 
First: Yes it is antifreeze. I specifically said ethylene glycol because there are other coolants out there these days.

Second: Go soak some seals in it. It does NOT dissolve rubber. It IS VERY slippery. That is why Mazda injected into their engines as a cold start assist. In Illinois (where I originally came from - just south of Chicago), the temperatures would drop so low that the rotary engines wouldn't crank fast enough to start. One hit on the anti-freeze injector button would let it spin right up.

Third: The best way to get it off of a windshield is straight gasoline. There was nothing wrong with the wipers. I think everyone from the colder regions has seen someone make the mistake of putting anti-freeze in the washer bottle. Only alcohol-based solutions work on glass. Here again, it is the fact the the ethylene glycol adheres so well to the surface and is so slippery that it causes a problem.

Fourth: If you don't think it's right for you--DON'T DO IT!
I still won't overheat my rotary to flush the cooling system like someone else suggested. I even read the link from the Mazda "expert" that was quoted and didn't feel comfortable doing it. Regular flushes are keeping my rotary just below mid-range on the gauge with the A/C on at 115 degrees in Phoenix!!

Amur_ 04-10-03 06:51 PM

Re: Ethylene Glycol
 

Originally posted by allenbillings
First:

Second:

Third:

Fourth:


Okay, I gotcha. :) I had some observations about coolant plus that story about the wipers, and I came to a conclusion that was wrong. I've no problem acknowledging that. I'm glad that you posted this because I want to share the most accurate 411 possible with people when these questions come up. And the next time this comes, in the Forum or elsewhere, I'll be ready (and way more helpful.) :)



hypntyz7 - that's the first time I've read a complete description of what the water injection method is meant to do, and what the results are (I'll take your advice anyday.) :bigthumb:
So I did it this afternoon. I don't know which of the vac lines go to both rotors, so I chose the one that was easiest to get at - the uppermost one on the front of the UIM.
The motor did NOT like it. :) I did the t-junction and dipped the hose into the water and the motor would bog. I finally found a nice balancing point where I would let the hose just barely sip at the water. The engine still bogged, but not as badly as before.

What vac hose do you use, and does the motor respond this way when you do it?

hypntyz7 04-10-03 08:02 PM

Amur:

You chose (for an s4 NA) the proper hose. This one feeds the 4 oil injectors, which siphon straight into the engine evenly. For an s4 t2, I use the ? shaped hose above the BAC, which tees evenly into both primary intake runners. For an s5 NA I use 2 capped off/unused nipples on the middle intake, by the acv...I use 2 vacuum lines of my own, teed into one, and dip that into the water. For an s5 t2, well, you have to get creative :D

BTW, bogging of the engine is normal. Water doesnt combust. In fact it cools the internals to the point that it's hard to maintain combustion (the direct opposite of detonation/preignition, which is where the internals maintain enough heat to ignite the mixture before it should be; this is why water mist injection is effective on high power engines). The key is to grab the throttle before you dip the hose in the water, rev it up to say 3-4krpm, and hold it, dip the hose, then give it a bit more to maintain that speed. After it is done drinking, the engine will slowly smooth out, at which point you can gradually release the throttle.

Amur_ 04-10-03 08:17 PM

Oh, I know that water doesn't combust. :D I was just concerned about how the motor reacted. I was revving her to around 4k (going by my ears) when I dipped the hose, and I still snuffed her twice. :) That compromise that I settled on was still at high revs. While I didn't rev the hell out of her, she was definitely getting a workout.


edit: I'll try it again tomorrow and report back. This time I'll be more generous with the throttle. :)

ForsakenRX7 04-10-03 08:35 PM

I have a n s5 turbo. I'm interested in tryin this as well. Any ideas on where to let it suck.:D

hypntyz7 04-10-03 08:36 PM

Yeah, thats all it is, balancing throttle with water. Sometimes I find myself giving an engine near WOT and holding it there, which isnt so bad in this case because it still doesnt rev over 4-5krpm.

hypntyz7 04-10-03 08:40 PM

On the s5 turbo, you need to find the large vacuum hose for the oil injectors on the back of the dynamic chamber/throttlebody. Take it off, put either a) a smaller hose inside it, b) a larger hose around it, or c) a metal or plastic tube to allow you to join another hose onto that one.

Amur_ 04-12-03 08:11 PM

Okay, did the water injection today. Had a fellow 7 owner on the gas and things went very smoothly this time. He had it around 4k and she took the water without bogging. Thanks, Kev. :bigthumb:

cmn65401 04-12-03 11:39 PM

did you know that the sub zero starting fluid in all mazda rx7s is antifreeze. call the dealer

nillahcaz 04-13-03 12:59 AM

did you know there was a service bulletin to REMOVE the sub-zero start systems?

rotary>piston 04-13-03 01:28 AM

that's just because it did nothing and was just adding dead weight

teg/rx-7 04-13-03 02:41 AM

ok i live in ontario, north of the border, it gets real cold here, am i going to have a hard time starting my 7?

BLKTOPTRVL 04-13-03 02:58 AM


Originally posted by hypntyz7
Amur:

You chose (for an s4 NA) the proper hose. This one feeds the 4 oil injectors, which siphon straight into the engine evenly. For an s4 t2, I use the ? shaped hose above the BAC, which tees evenly into both primary intake runners. For an s5 NA I use 2 capped off/unused nipples on the middle intake, by the acv...I use 2 vacuum lines of my own, teed into one, and dip that into the water. For an s5 t2, well, you have to get creative :D

BTW, bogging of the engine is normal. Water doesnt combust. In fact it cools the internals to the point that it's hard to maintain combustion (the direct opposite of detonation/preignition, which is where the internals maintain enough heat to ignite the mixture before it should be; this is why water mist injection is effective on high power engines). The key is to grab the throttle before you dip the hose in the water, rev it up to say 3-4krpm, and hold it, dip the hose, then give it a bit more to maintain that speed. After it is done drinking, the engine will slowly smooth out, at which point you can gradually release the throttle.

I used to "steam clean" my old piston engines by slowly pouring water through the carb. It always worked for me, but shouldn't you warn amour that water does not compress and that if he "injects" too much, he may break some internals?

http://www.physlink.com/Education/AskExperts/ae15.cfm

White_FC 04-13-03 03:57 AM


Originally posted by BLKTOPTRVL
...but shouldn't you warn amour that water does not compress and that if he "injects" too much, he may break some internals?

No, since we're talking about rotaries, not pissed on engines.

RX7_ZRO 04-13-03 04:12 AM


Originally posted by White_FC
No, since we're talking about rotaries, not pissed on engines.
LMAO

Anyway, interesting topic...I'd try that steam clean trick...just need some time and someone who knows what the hell is what in the engine bay, lol, I'm stupid when it comes to stuff like this...for some reason, looking at pictures or trying to find something by description never works for me, lol

BLKTOPTRVL 04-13-03 04:18 AM


Originally posted by White_FC
No, since we're talking about rotaries, not pissed on engines.
Why? Too much water is still too much water?

White_FC 04-13-03 04:25 AM


Originally posted by BLKTOPTRVL
Why? Too much water is still too much water?
I'd like to see you hydro-lock a rotary.
The only thing that happens if he injects too much water will be that the car will stall...

Jeseth Cloak 04-13-03 05:10 AM

I'm not very experienced when it comes to RX-7 "tricks" like most of you seem to be, but my engine is running strong at 180,000 miles and idles evenly. I redline once every day or two and change my oil often. Filters get cleaned every two months (K&N). I usually shift at 3,500RPM, ocassionaly at 5,500RPM if I'm in a hurry. If gasoline itself is very good at breaking down gunk and all sorts of buildups, why would putting water or other things into you engines clean it any better?


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