Further observation has now lead me to believe my car doesn't have an oil burning problem, and I am actually burning coolant. I have lost about 1/2 quart of water from my cooling system in about 10 miles of driving, so I guess I am going to research engine builders, as I believe I will need a new engine. Pineapple Racing comes to mind. Well at least this gives me an excuse to keep pumping money into my rx.

 

No **** sherlock. Everyone told you that it was coolant being burnt, since the smoke was white. It took you this long to figure that out?

BTW, you NEVER said the smoke had a bluish tint. You specifically said "The smoke is White with a blur tint (very faint)." You could have meant blue, but the way it sounded, you didn't. Also, oil burns with a very distinct blueish tint. Not "very faint" like you said. There could be a small amount of oil being burnt at the same time to produce that slightly bluish tint, but its probably not enough to explain the huge cloud.

 

One thing I really am disgusted with on this forum is that there are so many JERKS here that have taken the joy out of being RX-7 owners. For Pete's Sake, what value is there in your post, other than to shoot your mouth off. I love my car, and I love working on it even when their are problems. It is a learning experience for me, and I enjoy it, but some of you on here seem to take joy in shooting others down. I hope you are happy with your life, because it sure does make you look "low class" when you post like that.

 

I don't take joy in shooting others down. I simply was mad at the fact that you seemed to just ignore what some of us thought. My point was that just because there is a slight bluish hue to the smoke, doesn't mean its from burning oil.

I admit I was a little harsh, but I'm sorta tired of being ignored.

 

Ok now that’s the way RX-7 enthusiasts should treat each other. I'm sorry for ignoring you too. There were so many posts I couldn't keep track of who said what, and I was biased to think it was an oil problem, because I just changed my oil to 20W50.

 

You sure it's not an intake o-ring problem?

 

Take your rad cap off and start the car. Your rad shoould be full before you do this. Once the car fires up check your rad. If you have bubbles then youre deffinately burning coolant. Let me know what happens.

Thanks, Ed

 

Well I don't know if my coolant would bubble, because it was mostly just straight distilled water. Would it still bubble?

An Intake O-ring problem? I don't think so, because my intake is not stock and there is no coolant running through it like the stock GSL-SE intake. I have a Holley Carb kit from Racing Beat.

I drained all the coolant and ran the engine for a minute to see if the smoking would stop and it did, so I’m pretty sure that I can conclude it was coolant.

 

In my initial reading on Rotary care and feeding, I ran across an opinion that we should never run 20W-50 oil because it alledgedly doesn't scrape off as well and will leave more deposits making things worse not better. The author recommended a good quality 10W-30 oil sulemente. Think of it; MMO is thinner, not thicker than 30 weight.

 

If you have no intake o rings then it would have to be the o ring between the two housings. Mine is doing the same thing. 85 SE. There is a quick temp. fix. Do a search for coolant fix, it should point you to the right thread. It is however a temp fix, eventually it will have to be built provided that the fix works.

 

Oops, did I read your post wrong? The stock SE has no coolant running through the intake. As for a carb I don't know, but according to the book the carbed 7's DO have coolant running though the intake.
Depends on your mods I guess.

 

I've seen some photos of "pits" in the interior surfaces of the aluminum water-jacket. If a rotary overheats, the heat stress can cause small fissures / cracks to the water jacket; allowing coolant moisture to leak into the interior. This could very well be the problem.

This happened to me, once. I came home for lunch between work/school and let the car idle in the driveway to keep the ac running as it was summertime. I jumped in; running late, and was hauling butt down the road. When I came to a stopsign, my engine stalled...

I looked at the temp gauge and it was PEGGED. I popped the hood and discovered that the lower radiator hose had busted and the coolant had leaked out while sitting in the gravel driveway; under the car and I didnt notice it!

That engine creaked and ticked as it cooled down. It leaked coolant into the combustion area for ever after and if left for a couple of days, it created a white smoke screen through the neighborhood. Spark plugs had coolant on them, too.

Lesson: Never, never, never give a rotary engine the chance to overheat.

 

different viscosities are for different temps. Mazda factory recommended viscosity chart in the manual lays out what oil viscosities should be used at what temp ranges.

 

The stock GSL-SE intake manifold had coolant running through it I assume to help warm it up. My Carb doesn't have those lines any longer, so I plugged them at the engine. Make sense?

 

Appolegy (sp?) accepted Spinner. I over reacted. Its sometimes hard to read all the posts fully. But just so you know, all oil burns the same way, wether its 5W20 or 20W50. The only oil that burns different is synthetic. But I'm not going to go anywhere with that because I'll probably get flamed for bringing up the biggest controversy in all of rotary history.

 

Spinner, educate me.....I have looked through the Mazda book and it doesn't show coolant lines on the SE. If there are then maybe that is my problem. No tear down? Inlighten me on the location please. This could help me in assesing my corrective action.

 

I am at work right now so I can't look at my car, but I know there was a coolant line that came out of the back top side of the engine and went into the intake plenum, and then another hose that came out of the front side of the plenum and went into the back side of the water pump. I clearly remember this because when I took them off coolant came spilling out all over the place.

 

On the SE's there are 2 coolant lines which lead to the TB, no the intake manifold. The TB coolant hoses come from 1) the back of the water pump to the TB (Thermowax pellet, cold start assist), and from the green Thermowax pellet device back to the underside of the intake manifold at the rear of the engine block. This is the return to the system. When the car is cold, the thermowax pellet activates the 'Secondary Throttles' which essentially function like a choke on a carb'ed engine. These are the ONLY coolant passages in the upper and lower intake manifold system of the 13b SE engine.

On 12a cars, there are 2 'ports' in the lower intake manifold that route coolant from the block into and out of the lower intake manifold for the purpose of heating up the intake air charge for a better mix of fuel/air prior to combustion. These ports can be sealed off if you live in a warm climate, and often leak when the o-rings get old, leading to coolant pooling on the top of the lower intake manifold, or being dripped down onto the exhaust system where it's quickly burned off - this can be a mysterious loss of coolant if you can smell it, but not see it.

There are differences in the intake systems for EFI and carb engines around these coolant passages, as evidenced by a look at the gaskets for the 12a cars:



and the 13b EFI lower intake manifold to engine gasket - note the absence of the 2 center 'ports' for coolant to pass (note also the '6'-port induction template):



Hope this helps for clarity,

 

Spinner,

Running no thermostat on anything but a race car is a bad idea. When you remove the thermostat it is to allow the water to circulate unrestricted. Driving around at anything less than 7000-8000 rpm is to slow for that mod. At racing engine speeds (in certain classes) the thermostat becomes a restriction and the water is moving too slowly to remove heat from the motor.

Driving around on the street with no thermostat, the water moves to quickly to remove heat from the motor. Your temp gauge will accutally read normal, and infact the motor is over heating.

You situation is probably a result of both your motor over heating and then the subsiquint (sp) removal of the thermostat.

Ryan

ps. do you still have all of your fuel injection stuff??

 

Thanks Ryan, I realized this after the fact, but know I know. I have heard of people using restrictor plates instead of a thermostat, and plugging the bypass hole in the water pump. What do you think of that idea?

I do still have all the fuel injection stuff, except for my computer, which i think is called the ECU. Email me if you need anything.

 

Thats fine if you you intend to only use it on the track, if you are still doing autocross with it, you should stick with the factory Mazda thermostat. The thermostat elimination thing should really only be used on motors that are dedicated road racers.

Ryan