Icemark

NO NO NO- it (front cover O ring leakage) is only an issue if the front cover was removed and not put back on correctly or the wrong O ring was used or the wrong front cover gasket was used.


This won't be an issue unless the motor was recently done. It is not something that blows out after even 20K miles. If it is bad it will blow out within the first 10K miles of engine usage.

Bad info, bad bad bad.

88 rex turboII

what about the thermo pellet at racingbeat what do those do?

apreludem

i think those replace the stock one to always allow oil flow thus giving you good oil pressure all the time..is this correct?

88 rex turboII

i heard something like that.just wanted to know for sure.

Icemark

Yep, that is correct

NZConvertible

The stock thermal pellet only reduces oil pressure when the engine is cold (the rotor oil squirters are disabled to give faster warm-up). You still have more than enough oil pressure for the type of driving you should be doing on a cold engine.

apreludem

yeah..my engine when cold has normal oil pressure..once it gets warm is what worries me. When warm my idle is almost nothing for oil pressure and at around 3k rpms i'm hitting right in the middle of the 30psi and 60psi on the gauge.

NZConvertible

You should verify this with a mechanical gauge, but it does sound like the e-shaft thermal pellet has failed. I'd replace it with a new one, but solid pellets seem to be more popular...

homebrewer

No need to pull the motor to replace front cover and/or remove the oil pan. It can be done, it is not a hard job but a fairly time consuming one. I did it six months ago.

Also, don't be tearing anything apart until you check your oil pressure with a mechanical guage. The stock oil pressure guage is worthless, mine is off by 25 PSI which worried me until I got an aftermarket guage. I'm actually pushing 55 psi at idle on a warm engine and 75 psi at 3000 rpm. My guage reads much less.

apreludem

any recommendation on a gauge? and about how much? thanks...sorry to steal your thread too =(

felixwankel88

auto meter ultra lite is a good gauge, but u should make sure icemark thinks it acceptable to... cuz i give bad bad bad info

Icemark

well not normally, just this time.

and fix your signature... it is way too big images are limited to the same size as 6 lines of text.

apreludem

hmm...the autometer ones are like 40-60 bucks....any other ones for cheaper then that ? ones that actually work?

apreludem

sorry to revive this thread and i am almost possitive you guys are sick and tired of these oil pressure questions...but here is one more =)


Basically in one of the threads i was reading someone mentioned that possible causes for low oil pressure could be bad thermal pellet or O ring. So i started to read up on the symptoms of a bad O ring and Icemark mentioned that you would lose oil pressure at higher rpms and such....my question is do you also burn oil and is it visible when accelerating?

I am currently just experiencing what this guy wrote..exactly like he wrote it with lower numbers after warm up:
"Upon startup, when the car is cold the pressure is good, goes up to about 70-60 psi at 3000rpm and 30psi at idle like it's supposed to.

Once the car warms up it starts to drop and looks like this:
15psi idle
50-55 psi 3000rpm
60 psi 4000rpm"

instead of 50-55psi at 3000rpms i get around 40 or so ( according to the gauge in the dash)

I am currently in the process of buying a mechanical oil pressure gauge to confirm the readings of the one in the dash but until i get it i would like to learn more about this oil pressure problem so i can have all of my angles covered.

Thanks and sorry for the long and annoying post =).

Icemark

Yeah, that would suggest pellet failure.

If the O ring starts to go or was pinced (but has not blown out completely) the oil pressure usually drops around 4000 RPM.

So you would have

Idle=15-30 psi
2-3000 RPM = 50-60 psi
5000 rpm = 30-40 psi
6000 rpm = 30-20 psi

But with pellet failure you typically drop about 15 PSI down through the whole RPM range.

Now it would not burn anymore oil, the oil just gets dumped down back into the engine.

But an increase in oil usage and lower pressure at lower RPMs would suggest a O ring failure on a rotor.

apreludem

ah ok...so from all this info i have been reading, if the gauge is correct, then i must have a pellet failure. =( bummer.

I do read that it is not that difficult to fix, however. I have the video that explains the rebuild so i guess i'll have my hands full =( .

apreludem

and by the way, thanks icemark!

homebrewer

The #1 problem of low oil pressure in an RX7 is a BAD GUAGE OR SENDER. Do not go about fixing problems that may not exist. Please put a real guage on the engine and measure oil pressure.

My dash guage reads 20 psi low but my aftermarket digital guage is showing great pressure.

Icemark

While I would agree that you would want to check the oil pressure with another gauge before spending time or money, I would radically disagree with the #1 problem being a bad gauge or sender.

It has been my experience with over 20 years of RX-7 ownership that the pellet is the the number one oil system failure and much like the PD, replacement of it should be considered a reliability mod. The number two failure would be leaks in the oil cooler flexible lines. Gauge or sender failure is pretty low on my experience list.
Maybe because I have never ever ever had a bad gauge or sender in any SA, FB, FC, or FD I or any family member has ever owned.

Perhaps it is the oil I use (sharp Jab at Homebrewer). And the oil you use leads to more failures of the senders because they have clogged up.

Of course the gauge on the FB and FC are very simple to recalibrate as well even if there was a problem.