poor_red_neck

Ok, like I said, I am a COMPLETE rotary n00b....

I saw this thread, is a rotarty like a 2-stroke? I have to mix in the oil when I fill up at the pump???

If so, ARE YOU KIDDING ME?
If not, what the hell are they talking about?

13bpower

I has it's own built in oil injection system. Uses about a quart of oil from the engine every 1000-1500 miles.

AreExSeven

You don't HAVE to do it.

The RX-7 has an OMP (oil metering pump) which injects oil into the cumbustion chamber to help lubricate the seals. The oil obviously burns away because of this, so you need to add oil often.

The OMP is know to have problems though, so some people don't trust it because if it breaks and the engine isn't getting lubed correctly it is not going to last. People remove the OMP and block it off. Then every time they fill up their gas, they pour some oil into the tank (premixing), so that it gets into the combustion chamber as if it were being injected by the OMP.

If you leave the OMP in, you do not have to premix, but you can for added safety.

RETed

http://fc3s-pro.com/TECH/FAQ/premix.htm


-Ted

1987RX7guy

iTrader: (3)

yeah it is just a hell of a lot better to use two stroke oil than regualr motor oil.

GTIguy

Ok after reading all this I only have one question. Does the engine still burn about a quart a month with the OMP disconnected? Also the article from FC3S, they say that there could be problems when the fuel injection turns off when the throttle is released... Has anyone had any known problems from these cases? I would really like to know.

1987RX7guy

iTrader: (3)

The engine should no longer consume that much oil since the two stroke is being injected by the fuel injectors. The lack of injection when off the throttle is not a big problem since the two stroke is designed to leave a lubrcating layer even after burned durring the combustion cycle.

l33trx7

are there any problems with the oil clogging the injectors? Also what about the issue of uneven mixing? I'm not bashing premixing, Im just curious.

1987RX7guy

iTrader: (3)

well on the mixing question: I only pump after going for about 300 miles or so when the fuel light comes on. then I put in the 16OZ of two stroke and pump gas. I think that 15 galloons mixes it up nicely. Plus the oil i use is TCW3 certified so it stays suspended in the fuel indefinatly. On the clogged injector thing I don't think it does. I doubt anyone would fail to mention that if it had happened to them.

AreExSeven

I don't think the injectors are the problem. I think its the OMP itself, and sometimes even the lines, which break really easily.

The ratio of mixing can fluctuate enough that it does matter how much you put in. As long as you have a general idea of how much per gallon, you should be ok.

l33trx7

ah. I doubt I would go to premix. Knowing me I would mess up big time. Either way thank you for answering so quickly. ^_^

1987RX7guy

iTrader: (3)

well there are those setups that use the OMP to inject two stroke and all you do is fill up a little tank and keep the leve up. so you don't have to remember when filling up but you are still reling on the tiny injectors to to the job well.

J-Rat

iTrader: (2)

Premixing has been proven to not only distribute better, it also burns cleaner.

Jarrett

theonlygreat

here's a question just out of curiosity, when fuel is injected into the intake manifold it turns from a liquid to a gas right? so what is the oil doing during this phase? and does anybody have an oil slick in their manifold from premixing?

1987RX7guy

iTrader: (3)

haha


the oil burns also but as it burns it is designed to leave a lubricating layer behind. look for my thread and follow the link and read it carefully it is all outlined there.

christi

A forum user on here known as "billy" .... he did the 2-stroke. After trying it out, his car started to overflow and coolant gushing out of his car. We are still uncertain as to what caused that problem, either...but that is the ONLY problem he had (only thing I saw anyway) after he tried to 2-stroke / premix.

Otherwise, I think it's pretty cool.. I just wouldn't do it if I am not having any failure problems with my OMP.

edit:

whoops, maybe my response has nothing to do with you, but I thought I'd post.

RETed

Actually, that's not quite correct.&nbsp The fuel is still finely atomized into the intake charge.


-Ted