(ENGINE) Internal engine cleaning. What one can learn when he searches.
 

It is amazing what you can learn when you do a little searching. What turned into "Can I/Should I steam clean my engine?" turned into a full blown research into the best way to clean a rotary.

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This thread pulled up a member who said steam cleaning is a no-no.

https://www.rx7club.com/1st-generation-specific-1979-1985-18/my-problem-steam-clean-290236/

However, Rotary Resurrection doesn't say anything ill about doing such a procedure.

http://www.rotaryresurrection.com/1s...injection.html


Vipernicus' thread in the Archives says to use a spray bottle and to stick it down the carb. Tho, what I find discouraging is how A LOT of threads focus on 12As and not 13Bs, due to most members owning the former, not the latter. I wish there were more threads for us 13B owners. :( Makes me wish some Archive threads were updated to help the EFI owners.

https://www.rx7club.com/1st-gen-archive-71/other-decarbonizing-rotary-featured-article-281207/

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Then I stumbled across this thread asking about the INFAMOUS SeaFoam. And, Trochoid's first response gave me a lot of think about.

https://www.rx7club.com/1st-generation-specific-1979-1985-18/sea-foam-561878/

And, in this thread, I can't believe I made such a newb remark. :rlaugh: Thanks to Trochoid for schoolin' a newb. :lol: AND for later on posting the best advice yet.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/anybody-use-seafoam-rotary-545613/


All this searching stemmed last night from me just wondering about doing steam cleaning on my motor. I have a gallon of (unopened) distilled water and also a spray bottle. Now, I'm not sure which method I should persue.

• My 13B has 200,500 miles on it.
• I run Royal Purple synthetic oil/gear lube throughout the drivetrain.
• I do not use premix.
• Usually, when my gas tank nears 1/4, I dump in a can of SeaFoam and RUN IT.

Now, after doing all this searching (and quite possibly more still after I post this) I'm wondering and considering about what would be the best course of action. This is a list of possible things to do. Depending on what people say, I'll go out and do it.

• Run 250:1 premix through the gas tank.
• Have the top vacuum port on the front of the dynamic chamber suck in the gallon of water while keeping RPM past 3K.
• Have the top vac port on the front of the DC suck in SeaFoam.
• Have the brake booster vac line suck in the gallon jug.
• Have the brake booster vac line suck the water via the spray bottle.
• Have the brake booster vac line suck the whole can of SeaFoam.

Any thoughts, suggestions, comments?

I was told by a few knowledgeable members that depending on how the previous owner treated the car, I should have another 50K miles left in it. Which is a good thing because I'm not making the money to do a rebuild. Yet. I'm just looking for health and longevity. :)

Thanks for compiling all the info but i think decarbonizing a rotary is easy. Don't waste time with a spraybottle of water, that takes forever.

1. Buy a big can of Gumout Carb Cleaner, spary it thru the intake after the AFM with engine running. It'll clean out the throttle plates, plenum, and motor too. Spray the whole bottle, you'll be amazed how much better it runs.

2. Put two bottles of SeaFoam in the tank and drive it like you stole it for 30 minutes.

Now when people say to induce it into a vacuum line into the manifold, is it like just taking some 5/16 hose or whatever, into a nipple on the manifold, and just pouring it in or will the engine suck in as much as needed at a time? I am wanting to try this sometime.

Tilt the can upside down too, right?

You must have spent a lot of time researching last night, well done. The threads you've cited cover decarbonizing as well as any I've seen. The only post that I disagree with is the one that states there's a danger of hydrolocking the engine. While this is common and can easily happen in a piston engine, it's nearly impossible to do with a rotary.

As to which vacuum line/port to use for ingesting of either the Seafoam or water, I'd need to look at the colored vacuum diagram that's floating around in many different threads. My personal opinion is to ingest either liquid at the earliest point of the intake system as possible. Reason being that the dynamic effect the FI engines makes use of pulls exhaust gases, along with building up carbon deposits all the way up to the Dynamic Chamber. I've found some DCs, in both S3s and S4s heavily caked with carbon. That carbon build up is the main reason the BAC valves need occasional cleaning.

You should be able to find one of the vac ports the go directly to the DC, that's the one I'd use.

Taking an extra piece of vac hose, (5/16"), connecting it to an intake nipple/port and dropping the other end in a container of Seafoam or water will suck the container dry in no time, just like using a straw on a glass of chocolate milk.

Great info but I stand by steam cleaning. I've never had an issue just a smooth running motor!

The vacuum diagram for a 13B. Hey, Jon, would this be considered Archive worthy? :)


https://www.rx7club.com/attachment.p...1&d=1199062215

Forgot to include this.

The vacuum port Trochoid is talking about is the dark purple one located right under the BAC valve labeled "Manifold Vacuum". :)

So I take it as a bad thing?

Reason being, I am getting a Lake city side draft much like this one:

https://www.rx7club.com/showpost.php...55&postcount=3

I guess my best bet is to run it through the tank.