Pocket Trey

Is using Motor Flush safe for 1gen RX7?

I have been using Motor Flush on pistons all my life. It works great!!!

I am unfamiliar with the effects of it on a rotor engine, especially with the OMP working.

Is it safe to use? If so, do I have to disconnect the OMP lines of for the 5 minutes it takes to flush the engine?

Please send comments.

Jeff20B

iTrader: (13)

I'd say it is not needed.

Pocket Trey

What????

The flush procedure as a whole or disconnecting the OMP?

Do you think is a good idea to flush it?

I have owned the car for a week now. It runs good but I always perform this procedure on all my cars especially when I have to replace the oil pan gasket. My gasket is leaking so that is why I want to do that now.

Thanks

Jeff20B

iTrader: (13)

If you've gotta take the pan off, why bother with the flush? I say take the pan off, clean it manually, since for one thing you will do a far better job than any product like that could ever do, and put it back on with RTV and maybe a gasket (some like the gasket while others don't - I've tried it both ways and prefer the gasket).

Don't touch the omp unless it is leaking.

Pocket Trey

I am trying to understand the ratinale in your answer.

The motor flush will clean all lubed components to include the oils lines to and from the Oil filter and oil cooler and the OMP and the lines that feed the carb. This will dislodge any crud on those lines and crevices.

Motor flush is not for the oil pan.(only)


Now if there are no other components I need to concern with then yes your answer would be right, but I find hard to believe that there is nothing else to clean but the pan.

Thanks

PercentSevenC

Waste of money and a bad idea anyway. It's basically just kerosene; it'll strip the oil film away from the bearings. Besides, if you're changing your oil regularly it's completely unnecessary. If you aren't, you might dislodge something and cause blockage in the oil passageways. I wouldn't do it, especially if you don't have a good oil pressure gauge (the stock one isn't). If you feel like you need to use something, use Seafoam.

blackdeath647

iTrader: (2)

i started doing a bit of research not long ago, maybe a week or two, and decided against it basically because, well they're good for piston engines, takes away all the oil residue, but due to the fact that rotaries need the oil...i wouldn't risk it, but that's just me.

Rogue_Wulff

The flush will not get into the main body of the oil cooler. Until the oil reaches ~160F, most of it is simply bypassing the oil cooler, due to an internal thermal bypass.
Any product that does get into oil cooler, would stay there when you drain the oil, and be reintroduced into the engine later. (not good)
About the only area in a Rotary that can have any sludge buildup, is the oil pan itself. Therefore, I agree with Jeff. Skip the flush.

Pocket Trey

AWESOME POST



That is why you start with a cold engine and do it for three minutes only.

I will do it and post the results later.

I believe this will give new life to the engine as it has done to ALL of the cars I have owned before.

Thanks
Juan

djessence

I believe its gonna **** ur engine but to each his own at the worst or be a complete and utter waste of money and time at the best..

You asked for the opinions with rationales and advice and shunned it.

A key bit of advice is the majority of products that are good for pistons often end up harming rotaries.

Kentetsu

When you're done running the flush through your car, come back and talk to me about how to stop the smoke screen coming out of your tail pipe...

I've tried this type of product 4 times, and it ruined every motor I tried it on. What can I say, I wasn't always this smart. Every motor smoked afterwards...

Pocket Trey

Were they all rotary engines or not.

I have used this product over 15 years now and NEVER had a problem.

This is why I asked the question and no one has given an answer with facts as to why it is not good for rotary engines.

blackdeath647

iTrader: (2)

idk if anyone HAS tried it. I know i haven't simply because i didn't want it ******* up with the omp nor anything like that, ....if you still wanna do an engine clean up and ****, just use Seafoam man, it works like a charm, and it doesn't hurt rotaries.

bliffle

Pocket,

You seem determined to use this stuff on your car regardless of what experienced rotary owners say, so go ahead and do it! Then report back here on how it goes so that we know and learn.

I notice that you are new, only 22 posts, and I wish you success. May you keep on posting. I just hope that you don't blow your engine and then go away telling everyone you know that rotary engines are no good, that yours blewup in spite of the special treatment you gave it.

blackdeath647

iTrader: (2)

+2 on that lol........anyways here's a link to my thread which quickly changed my mind about using the motor flush...once again it's up to you.....https://www.rx7club.com/1st-generation-specific-1979-1985-18/seafoam-760432/

Rogue_Wulff

I tried to give you the facts. You even said it was an Fact 1. Most, but not all, oil bypasses the oil cooler until the oil temp reaches ~160F.
Fact 2. The flush that does get into the oil cooler, will remain in the oil cooler when you drain the oil.
Fact 3. The flush that remains in the oil cooler, WILL get back into the engine later. This is not good.
Fact 4. The oil pan is virtually the only place an sludge can form in a Rotary.
Since you are already planning to drop the pan in order to fix an oil leak, skip the flush, and just clean the pan, if needed, while it's off.

Pocket Trey

This is ridiculous.

22 post does not make me inexperienced. It says I dont have time to do computer stuff after I am done working. I an mew to the site yes.

Just because people have 2K posts does not make them expert or experienced. It makes you a heavy post that's all. In fact, it says you spend more time behind the computer than working on your car. LOL

I am a mechanic(12 years now). Just not an auto mechanic, but I work with turbo shaft engines in the aviation comunity. Very similar to a rotary engine minus the combustion chamber.

Give me facts and I will listen to you. If you dont have the facts and you post your opinion thats fine too but dont make it seem like I am an (a hole) when I just want to be convinced with facts not myths.

If you have done the procedure in a rotary and was a negative outcome I want to know why it was such and if it was because of poor employment of the product or or not.

Ehron

iTrader: (1)

I am helpful.

Pocket Trey

It was an AWESOME POST

It has many facts.

Yet the oil cooler will not open until it reaches 160deg right?
Then it is safe to say that I do not have tio worry about the product entering the oil cooler and getting trapped inside it because when you start the procedure you do so with a totally cold engine. Run it for 3 minutes and shut off. That does not let the engine to reach the 160deg.

Tell me if I am missing something there.



OOOOOHHHHHHHH

Wait

I just read your post once again

Sorry

So the oil cooler will trap some oil even before it reaches 160deg?


WOWOOWOWOW

That really changes my perspective then.
I do agree that if some is trapped it is not a good thing.

Confirm this is what you mean. I thought there was a check valve to the cooler that opens at 160. You are telling it will still let oil pass through?

Sorry for the confusion.

Pocket Trey

I

ireyes

I have a GSL 1985 with 269,000 miles. I read a thread that the person suggested to flush the engine with Seafoam and then add water thru the intake and manually rotate the engine and leave it like that for a day. Once done I changed the plugs. rotor cap and wires. Also changed the oil filter and put back the carb. It smoked for a while but after a week, it only smokes when its cold for about 10 seconds. Obviously the motor has not been touched internally but it runs great. Later on I placed a new oil pan gasket and the pan was clean.

Pocket Trey

Did it smoke before you did that procedure?

Mine does not smoke now. I will perform the procedure today and will post results either tommorrow or the next day.

I will take every precaution. So I will probably remove the oil cooler and clean it after the flush and before running it again. It is pretty simple to do anyway. so why not.

Rogue_Wulff

The bypass doesn'y open till around 160F. However, it does not bypass 100% of the oil, it mearly allows the oil to flow thru an internal hole or thru the oil cooler. Once the oil leaving the cooler reaches ~160F, the bypass closes the internal passage, forcing all the oil to flow thru the cooler.
If you insist on running the flush, the definately flush the oil cooler afterwards. Just be aware of the almuninum crush washers used on the 79-82 front mount oil coolers. They are a one-time use item. Trying to re-use these have resulted in many oil coolers having cracked bungs where the lines attach.
If you have an 83-85 12A, it doesn't have a real oil cooler anyways........

Pocket Trey

Thanks

Good info. Pretty much what the book says on the subject.

My plan is to get the flush done, remove the little oil cooler and remove the bypass valve(Book says it opens at 149deg) I will verify that too. Flush the oil cooler separately with oil and reinstall.

There are 2 washers and o-rings that are one time use in my oil\c cooler (according to the book). I won't mess with any of that. I will remove it just to be on the safe side since you guys are so enfatic about it, but in all honesty, if you look at the size of the oil cooler and the amount of fluid that can be trapped inside it to me is of no real concern in comaprison with the amount of oil that circulates through the system.

We use something similar with our turboshaft engines and it works like a charm although it is highly corrosive and not performed well can destroy a 1M engine within 30hours of use.

The substance we use is called "Gas Path". Smells like diesel but NOT Very corrosive nasty stuff.

Anyway if you think of anything else, let me know. In about 3 hours I will get off from work and go work on the flush.

Fingers crossed.



One more thing.

Discussions like this is what let us make informed desicions. In no way there was an intent to discredit or belittle any of the people giving suggestions, however, I think I will be doing a lot of good to my engine(I hope I'm right). On the other hand if I am not; I can't say I didn't know better. You guys mentored me at it's best. Thanks for that.

We can all only hope that this procedure does as well as I think it will and that I can document the success for others like you guys benefit and bust the myth of flushing the engine.

Crap. I forgot my camera. The car is cooling down. I guess I will use my cell phone camera and see if that's enough.

djessence

Discussions like this will always exist, IE synthetic vs non synthetic, fram filters etc.

Let us know what happens, just seems like far too much risk and effort to go through