Yesterday when I was driving my RX-7 it started pouring out a huge could of smoke so I removed the rod from the OMP so no oil would be pumped into the engine, and shortly after the smoke stopped, but today it happened again, but when I removed the linkage to the OMP the smoke didn't stop. There was so much smoke it was like I dumped a bunch of MMO into my engine.

I changed my oil this week and put in 20W50. I noticed a raise in oil pressure. Could the increased oil pressure have caused a problem with my OMP, or could oil be getting past internal engine seals? The engine has over 100k miles on it. Maybe it's on it's last leg.

My setup:
84 GSL-SE converted to Carb
Holley 600 Racing Beat Kit
RB Street port exhaust and header
Stock Ignition

 

Geez, there is no way the OMP can pass enough oil to smoke that much, yet people still think it does... all the time it seems.

Your problem is oil seals/O rings and/or the springs behind them.

So in other words, even though the smoke may go away for a while (as the oil seals reseat themselves), the smoke will always return. It is also NOT caused by the OMP and never will be.

The only way I could see the OMP allowing that much oil into the engine would be if its internals were bypassed so the engine recieved full oil pressure through those tiny tubes, and even then, the internal diameter is so small that it's still highly doubtful. That's my story and I'm stickin' to it.

 

On David Lane's RX-7 website, he says that he had the same problem, and then he changed the oil to Valvoline and the problem went away. (It's anyone's guess whether the problem was actually solved by putting in new oil, or if it's something about Valvoline oil. He uses regular non-synthetic Valvoline oil, 20W-50 I think.) You might want to give that a try..

 

Others have said Valvoline is great oil to use too. I remember it because of the ironic brand name.

 

20W50 is what I use here in Cali... Don't know if that would be the right for you in Washi... check the manual.

 

20W50 for summer and racing, and 10W30 in the winter is what i run.

 

In that case that sounds right.

 

I had this problem, and it turned out to be the o-rings were cracked to ****.

The deteriorated water gaskets didn't help either.

 

Ummm, this may be a stupid question, but does the smoke smell like burnt oil? When I think of white smoke pouring out of the exhaust my first guess would be coolant leakage. Just a thought...

 

That's the same thing I thought when I first read the post too. Sounded like a water seal had let go and was dumping coolant into the engine somehow.

 

In my experience, yes, the OMP can pump that much oil. The cylinder with the black o-ring on it on mine seized in the OMP itself and was feeding the engine constant oil after being stuck open. It belched smoke and wouldn't stay running 95% of the time. Installed another used - but in good working order - OMP out of an 86-88 FC and the problem went away. My car was out of commission for a good couple weeks trying to figure out what the problem was, and a fellow SE owner (who's car is powered by a Haltech...sigh...money) finally pin-pointed it. I'm not trying to totally dismiss what you're saying Jeff...but you're wrong! Haha

Zac

 

Sounds like coolant to me. Does the smoke smell sweet?

And to inform anyone, Valvoline is absolute crap. I wouldn't put it in my lawn mower. I've worked in the oil industry for 3 years now. Valvoline had to put in 3 samples to get their SAE starburst when the new requirements came out. All other brands just took 1 to pass. I run Royal Purple, and premix the royal purple 2 cycle.

 

is shell helix a good mineral oil? What about castrol GTX2?

 

I used to use castrol before i went to RP. Shell (which now owns Pennzoil) has gone to a parafin base now.
AKA Parafin wax. Go with the castrol.

 

The smoke is White with a blur tint (very faint). It seems like oil to me because the exhaust tip is wet with oil residue. I am guessing because I switched to 20w50 that the increased pressure on my old 100k+ engine caused an oil seal to fail. Does that theory hold up?

No it is not sweet smelling smoke. It smells like a car burning oil, and looks like as much smoke as when someone does an MMO treatment.

Although it is entirely possible I have both an oil and water seal failure, because my thermostat did fail a week ago, and i removed it so there is constant coolant flow now, but if my engine did overheat it could have caused some damage to the water seals.

 

The smoke is White with a blur tint (very faint). It seems like oil to me because the exhaust tip is wet with oil residue. I am guessing because I switched to 20w50 that the increased pressure on my old 100k+ engine caused an oil seal to fail. Does that theory hold up?

No it is not sweet smelling smoke. It smells like a car burning oil, and looks like as much smoke as when someone does an MMO treatment.

Although it is entirely possible I have both an oil and water seal failure, because my thermostat did fail a week ago, and i removed it so there is constant coolant flow now, but if my engine did overheat it could have caused some damage to the water seals.

 

Just this once.

Spinner, if you removed the thermostat without covering the bypass hole, you probably did overheat your engine. The bypass hole must be plugged, otherwise, the cooling system is only like 20-30% efficient.

 

What do you use to plug the bypass hole?

My engine doesn't seem to overheat without the hole plugged. I'm running straight distilled water with a super coolent additive.

 

A 1/2" NPT pipe plug if I remember correctly. Or you could weld it closed if you are handy welding cast iron.

 

White smoke = water / coolant; blue smoke = oil.

 

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I don't get why you think its oil smoke. Oil ALWAYS burns bluish. If its white, its either just mist on a cold day, or its coolant being burnt in the engine.

 

you must not have read all of my posts. The smoke does have a blue tint.

 

I don't wanna hi-jack your thread here, but mine is white smoke with a sweet smell. I've determined that it is coolant. Is there any other cause, besides a bad engine?

 

bump

 

84SE - 178k miles, MMO added to the oil disintegrated the carbon deposits around the oil control seals on the rotors and thusly turned my otherwise clean running car into a SPYHUNTER smokescreener on cold start. Once the engine warms up, the oil control seals expand and seal once again, leading to no more smoke.

Smoke is blue-tint, and thick and doesn't dissipate in the air. It's oil burning.

There's no way to fix this without an engine teardown and rebuild with new oil control seals. Join the club. Switching to 10w30 during hot summers here seems to have reduced the oil consumption due to increased oil pressure from cold start oil viscosity. High pressure causes more smoking, such as using 20w50 oil or revving the engine up beyond about 6k rpm. The high pressure allows more oil to flow past the oil control seals and get burned in the combustion chambers.

FYI, the oil is entering the intake charge due to the vacuum present there, from there it gets carried into the combustion chambers and burned, resulting in a well-lubricated engine! I picked up about 2-3mpg in fuel economy when my smoking started, but also add about a quart of oil every 2nd or 3rd fillup (500-600 miles). That's a lot of oil, but I never worry about lube starvation! HTH,