Latin270

I wonder if this will work on my girlfriend! lol

Manntis

asked NAPA to order it, they said they normally carry it but are just out of stock ATM. Last guy I talked to said they don't carry it at all. I wish they'd stick to one story!

85 FB

Fair enough. All hail the mighty 13B and all its fuel injectedness!

trochoid

iTrader: (6)

Ah, but there's the rub. If you want to clean the dynamic chamber and the butterflys in the the tb, adding Seafoam to the tank won't work, all those parts are pre-injector. To clean those parts, and they do do need it occasionally, one needs to tap a fitting in the intake duct, just before the tb and use the vacuum draw method.

I have seen dynamic chambers so carboned up that I have had a hard time even beadblasting the insides on them.

85 FB

So, how would you utilize a vacuum draw method in the intake tube? Wouldn't it just be better to put it in a pump-spray water bottle and spray it into the throttle body?

Anex 570

Roger that, I've delt with a few like that. Days in simple green helps though. The biggest problem I've had trying to spray before the throttle body is have the hose blow a flame back out at me heh. Removed the AFM once too.

trochoid

iTrader: (6)

The afm needs to see air flow for the engine to run and the revs need to be kept up because adding any liquid into the combustion tends to kill the engine. One way around this is to prop open the door on the afm, but it can be tricky matching the afm signal, throttle opening and injector pulse width so that the engine runs well enough to accept the Seafoam.

It's easier to tap the intake duct for an 1/8" barb just before the tb. Cap the barb when done, it will be there for the next cleaning.

85 FB

So, with a barb fitting in the intake hose right before the throttle body will draw a vacuum to suck the SeaFoam out of the can? Or, would I kind of have to help it by nearly turning the can upside down, provided of course I seal up the top of the can to keep it from leaking. I've just never done, nor heard of, something like that before.

teamzzyzx

Since there seems to be several different methods to get the SeaFoam into the engine, what do the 12A guys do? To me, it seems like adding it to an 1/8 thank of fuel and sucking it in the vac. line is the same? It all feeds to the carb, am I right?

Just lookin for some clearification, becuase I just bought a bottle of it at Pep Boys last night and its sitting in one of my bins waiting for the 1/8 tank mark.

Thanks

Kentetsu

Yeah, just dump it in the tank and you'll be all set..

trochoid

iTrader: (6)

Ok, I'll try and coallate all this in one post so one doesn't have to read the entire thread.

12A Carbed engines:

Adding to the tank: Will clean the ENTIRE fuel system, from the tank to the exhaust ports and everything in between. Waiting till the tank is down to 1/8 th full or so, cleans it harder and faster. Adding it to a full tank would be a good preventative maintinence proceedure, i.e. every oil change.

Inducing through a vacuum port: Does not clean the carb, it by passes it. This is a good method to try and unstick a seal due to carbon build up. Drop a spare vacuum hose in the can, keep the revs up just enough to keep the engine from dying, no more. Suck in 1/2 of a can and shut the engine off. I usually let the revs drop and allow the Seafoam to kill the engine. This keeps the mix in the combustion chamber so it can work on the carbon. Let the car sit, overnight if you can. Fire the engine up and run the rest of the can through it, then take it out for a hard drive.

13B FI engines:

Intank method works the same as the carbed engines, with the following exception. The fuel/Seafoam mix cleans everything AFTER the injectors inside the engine. It does not clean the Dynamic Chamber or the throttle plates.

Now you are thinking, what difference does this make, the fuel doesn't get that high in the intake and it should be clean anyway. WRONG. This is because of the dynamic effect of the intake and the exhaust overlap rotarys have. Exhaust gas gets pushed into the DC, which increases the intake charge into the other rotor. Exhaust gas carries with burnt and unburnt fuel mix, and lo and behold, carbon. Eventually the carbon deposits build up inside the DC and on the inner side of the throttle plates, which can cause them to stick and/or not close as designed.

To clean this area, the Seafoam must be introduced before the throttle body, but the first vacuum port is the gasket/vacuum port plate between the throttle body and the DC.

Therefore, I recommend tapping a 3/8" NPT X 1/8" hose barb, just prior to the tb. There will be some vacuum in the intake duct, not a lot, most of it is right behind the throttle plates. You may wish to use the spray can Seafoam, with the plastic extension on the nozzle, in this application. When done, cap the nipple for the next time. Cleaning the tb and DC isn't needed often, annually at most. This is also the preffered method for unsticking seals as noted in the 12A part above.

Now, as a side note for the vacuum method. Water works too, and no, before you ask, you cannot hydrolock the engine. It works in the combustion chamber only, it needs the heat and compression to turn to steam. It is not as effective as a chemical solution. I often use it as a follow up to the Seafoam treatment.

So there are the Seafoam answers. Any other questions, I have a novel answer, think for your self, it will give you a better understanding of 'How It Works", lol.


Jon, this thread is making me think too hard with all of the questions. If you don't archive the thread, at least do this post.

Manntis

I just dumpd a bottle of it into the Dodge at 3/4 tank, since it says it treats up to 95 litres.

Within 1/2 hour my idle was a lot smoother.

teamzzyzx

Thank Trochoid, that was the post I (and pretty sure others) were looking for. It was a bit confusing reading all these and trying to decide on a method to use.

Manntis

It does? I thought the DEI worked by using the intake charge pulses to create virtual supercharging, much as a tuned header works by using exhaust pulses to create a vacuum and increase scavenging.

trochoid

iTrader: (6)

Good, now all of you can get busy cleaning thier engine and fuel internals, instead of sitting online and asking questions. lol.

While doing a post like the one above can get tedious at times, it has benifits for me. It makes me think about all of the systems and how they work together, which in the long run, gives me a better understanding of them, which hopefully, I have passed some of that along to others.

It's not really a question that I am smarter or know more, it's that I am stubborn and believe that I am smarter than the 'machine'. That stubborness forces me to learn what is going on in the backround of the different systems. I still have a long ways to go before I am comfortable with my understanding and knowledge of all of the systems invovled in our 7s.

Learning and gaining knowledge has always been important to me. If this forum wasn't here, I would be way light years behind on what I know. Between working on the 7s, the FSMS and the forum, my knowledge base a grown quite a bit. The forum is #1 on the list for knowledge gained, the hands on experience is a close 2nd. The FSMs are a back up for the male ego that inately says, ' I don't need no instructions".

trochoid

iTrader: (6)

It's the overlap on the exhaust cycle. If the exhaust pulse only pulled the next intake charge, there wouldn't be any carbonization in the DC. I don't disagree with your statement, but I have no other explaination for the presence of carbon in the DC.

I've seen the same thing on tb intakes on piston engines.

85 FB

Actually I have a hamster inside mine running after food pellets to keep the thing from decarbonizing.

I find that innovative hands-on is much more informative, and entertaining, than real base knowledge.

Manntis

My understanding of the DEI is thus: The exhaust pulse doesn't pull in the intake charge - what i'm saying is that the intake pulses are tuned in the DEI so one going onto one rotor creates a vacuum that helps draw the next into the other rotor after it, thereby 'pushing' in an intake charge at slightly above atmospheric pressure. All this occurs independant of the exhaust pulses, which are isolated in the exhaust, not intake, system.

Of course, if you've other information illustrating that in fact the DEI receives exhaust pulses and my understanding of the function of the DEI is flawed, I'd like to see it so I don't go on passing along erroneous infomation

trochoid

iTrader: (6)

Your are correct on the dynamic effect, no arguement there at all. The thing is, with the exhaust, is that not all of it is exhausted in each cycle. The bathtub, (compression chamber), is longer than than the exhaust port is high, and never completely expells all of the burnt fuel mix, it carries some of it back into the next intake cycle. That overlap of the exhaust is the explaination I have for the presence of carbon in the DC.

If you look at the rotor as it passes the exhaust, you will see what I mean. Also, with the dynamic effect working, it is pulling air from the path of least resistance, and the exhaust still has some pressure behind it. This results in some dilution of the intake charge by the exhaust.

Kept spreading the dynamic effect facts, I don't think many of the FI owners understand it.

85 FB

*raises hand* I would be one of them, but I think I'm slowly understanding it.

DC = dynamic chamber right?
Now what is DEI?

Manntis

DEI = Dynamic Effect Intake. It's what Mazda called the DC on a GSL-SE.

85 FB

Time to relearn everything all over again.

boyee

iTrader: (3)

i just seafoam'd my car for the first time. good stuff. lotta smoke though because me and my friend sucked half of the seafoam with a vaccum line from the carb. then poured the rest in the tank. it improved the acceleration because now it is smoother. also hope i cleaned out a little of the original cats. but now i gotta but in the new bone[r]z cat to pass smog.

p.s. when i got home from driving it in the high rpms to run a little seafoam in the tank i washed my car, my baby. i love my car!!!! long live original first gens and the rotary!!!

Kentetsu

Seafoam, it's not just for breakfast anymore...

SSRx7

I agree with some of the exhaust gasses and carbon remaining in the chamber as it continues on to the the intake port. I would assume that as the intake port is cleared by the rotor, the remaining exhaust is still slightly pressurised, and since the rotor has not yet started to pull away from the intake port no vacume is yet present, so the exhaust gas is in effect pushed into the intake port, which would cause carbon to have a chance to build up in the DC.

Now, lets throw a wrench into this theory. On turbo charged engines, the intake side of the engine is constantly under pressure, since the turbo is constantly pushinng air in. The questions are 1) is the intake charge pressure higher than the the remaining exhaust being forced out of the chamber? and 2) If the intake charge is at a higher pressure than the remaining exhaust charge, does carbon build up in the DC of a turbo engine? My reasoning is that if the intake charge is at a higher pressure, then the exhaust would not be able to find its way into the DC, because it is meeting and and being forced to stay in the combustion chamber by the incoming pressurised intake charge.


We use Sea-Foam at work for injection cleans on piston engines. The other thing that I found out is that Techron is one of the best fuel additives for piston engines, because it helps break down all the deposits in the valve train. This is actually the stuff recomended by GM engineers, but I don't know how it would do for Rotary engines. Also, have not really compared the Techron to Sea Foam directly, so I can't say which is better.

Later,
Bill