nolimitniceguy

if you overfilled the oil on a regular piston motor, the oil would come out of the rear main seal... what happens if u over fill a rotary?

Larz

It will reach the combustion chamber like in a piston engine if it gets too high I think.

Matt Hey

You can kill some engines by overfilling them too much. Overfilling a rotary by very much (1/2 qrt+) results in more oil being pushed into the intake (eccentric shaft ventilation system) that can build up in the intercooler or be blown out the blow off like valves. I don't know what severely overfilling a rotary engine would do.

nolimitniceguy

my oil level were low so i filled about 1/2 qt and i noticed some oil had dripped, but i couldt find where it was comin from, i checked my blow off valve and there was a lil oil in it

EfiniBoy01

That sucks, just try not to overfill it...but I do once in a while...my car is fine...

nashman69g

iTrader: (3)

Can we get some facts...

JHew84

iTrader: (9)

well the issues with overfilling a piston motor involve crank case pressure, as well as excessive oil sloshing, among others but those are the 2 most prominent... with more oil in the crank cause that will raise the pressure, which will blow out all sorts of seals, also if you overfillt he oil the crank will start to churn it more than it should which will cause the oil to get frothy and in the end instead of oil getting into all the passages you end up with a lot of air and bubbles...

i would assume something along those lines would happen to a rotary as well, as far as the oil pressure is concerned, but i really dont see any reason why it would get frothy and oil starve the motor... please someone with more knowledge step in and correct me if i'm wrong, or elaborate on what i've already put ...

Herblenny

iTrader: (13)

Really?? I think you might see oil in your intake because of your turbos not because of some eccentric shaft vent system.

I would also like to hear from some experts

TRUST

I've overfilled both of mine several times and never had issues, more oil is good for turbo driven vehicles, especially mine since they burn oil... hehe.

Matt Hey

There are other reasons why oil gets in the intake system because of blow-by, like poor sealing of the combustion chamber and very hard cornering. Overfilling the oil makes these problems worse. RX-7 racers on R compound tires run with low oil and a catch tank. They would love to have the extra cooling capacity of a little more oil but if it ends up in the intake it just makes a mess.

SayNoToPistons

...

nolimitniceguy

how/why does it get into the intake?

LUPE

I run 6.5 quarts in my RX7. You ask how I get away with it? I use a 50/50 mix of 0-30 coastal and whale oil.

ecarver2

The secret to his low weight and massive power is out...

Matt Hey

The oil gets pushed up the oil filler neck by blowby gasses and pulled into the intake by suction from the turbos. There is a hose from the oil filler neck to the plastic inlet pipe on the first turbo. The harder the cornering and the more boost, the more oil is pushed/pulled into the intake. Every RX-7 I've seen has oil in the intake. Overfilling just makes it worse.

nolimitniceguy

im takin stuff apart trying to find where the oil is comin from, i took off the elbow to the intercooler, i know its ok to have a little oil in there, but how much is too much?

Mahjik

iTrader: (1)

Llight coating is fine. It shouldn't pour out onto the floor.

nolimitniceguy

i took the intercooler off, and it had a considerable amount of oil in it, id say 2 or 3 oz.