skotx

The other day I was going to take the car out for a spin. It didn't start on the first try, which is very uncommon. Got it started and had a lumpy idle, which smoothed out in about 10 seconds. About 1/8 mile away from the house the low coolant buzzer goes off and I've got white smoke coming out of the tailpipe. The car was at about 45C degrees according the PFC.

Sounds like an O-ring, right? The next day I added some coolant and started her up: no champagne bubbles or white smoke.

More info, if it matters... my gas tank is more empty than I usually let it get and this was the first tank that I ever used MMO. Does that stuff mix well with gasoline, or was I trying to send a higher concentration of MMO through my injectors?

Thanks, Scott

Sesshoumaru

iTrader: (1)

If that mmo is standard oil it causes problems. Pre-mix is what is used (mixes and burns better).

you also need to put it in before you fill up (to mix it). You might have had a high concentration settle to the bottom.

Rated R1

I have been running MMO for over two years without a problem. Several other forum members on here run it as well!

Sesshoumaru

iTrader: (1)

I don't know about MMO but normal oil is different than pre-mix oil.

CCarlisi

I had the same symptoms and it was my o-rings. The car would run off one rotor when it first started then the other rotor would come on line after it pumped all the crap out of the chamber.

DCrosby

I thought we had no "O" rings.. I thought they were called water seals !? Or are those different from rotary "O" rings ???

spurvo

water seals = O-rings when coolant issues are being addressed... The water seals are litterally rubber strips coated on one face with teflon and joined together at the ends to make the O. Unless you get the aftermarket ones from someone (Pineapple, amongst others..).

skotx

Thanks for the replies.

MMO = Marvel Mystery Oil and it was my understanding that many people used this as a pre-mix. I guess I didn't do enough study because I don't know whether people use it pre or post fillup.

I'll check the coolant tonight, start it up, and go get some gas without pre-mixing, but it still seems to be toying with me regarding the o-ring failure.

paw140

Even if it was the MMO (and I don't think it is - it is miscible with gasoline), that still doesn't explain your low coolant buzzer.

SERIES7

I remember reading somewhere that there is a new and improved, stronger, more heat tolerant O-Rings? Can someone please confirm?

CCarlisi

There are more heat resistant o-rings, but combustion gas temp still exceeds the temp range of the 'upgraded' o-rings by several multiples so I don't see the point.

As I understand it (someone correct me if I'm wrong) O-ring death occurs as follows:
1. The combustion chamber heat output exceeds the cooling system capacity.
2. The metal components of the motor begin to expand and deform due to extreme heat and 'hot spotting. '
3. The rubber coolant o-rings are exposed directly to the same combustion cycle heat that was extreme enough to warp the metal.
4. The combustion cycle heat fries the o-rings.
5. The housings often remained in a warped state even after cooldown.

Therefore, upgrading the o-rings seems like trying to solve the problem after it has already passed through the fan (step 2). Even if the o-rings are able to survive the heat there is a good chance the housings will be warped.

mp5

iTrader: (3)

I think it is possible that under normal load the expansion of the motor and the subsequent "loss" of sealing by the o rings at "higher temps" could give you those symtoms,kinda now it leaks now it doesnt!

rx7_lover

mine with MMO for little over a year, no problem here

spurvo

CC, that makes sense, but you can also add that overheating the engine (seems to be in the 250F range from what I've read) will deform the housing to plate interface to epose the rings to exhaust gas temps. Once that happens, it's all over.

I ran MMO for six months with no smoking problems. I was running 4 oz per full tank of gas (like 1:400). Then I realized it made no difference as I'm running a thoroughly stock engine.

Enthu

iTrader: (1)

I ran MMO in my fuel for about a year, but recenty switched to AMS-OIL 2-stroke racing oil. The engine seems to like it more than the MMO. If you can find this stuff I'd reccomend it.

I'd heard MMO has a corrosive nature, and decided to not leave it to chance.

Fd3BOOST

iTrader: (7)

Uhh yea, they fix themselves..

Dude if the seal is broke then it is broke.
The rubber i snot going to meld itself back togther.