Heavy Smoking 1979 RX7

1988rx7 · 06-11-2008, 09:34 AM

Hi, I am new to site.
I owned a 1988 rx7 convertible for about 7 years, but last year she was killed by a little old lady.
Now I own a 1979 Rx7 that I am restoring. I got her painted, did the interior, changed the dash, she is almost ready...

But now I have a Big problem. She started smoking alot, I changed the oil one day and the next driving down the highway she began smoking so much I couldn't see the car behind me.

I parked the car thinking I broke an oil seal. Talking to a friend was told that maybe the rod from the carb to oil metering pump got stuck and was letting the pump inject lots of oil into carb, hence the heavy smoke.

Have verify the rod and its not stuck, when even further to lubricte with silicone that area.
After a week of the car sitting, I tried starting her, and she worked no smoke.
Took her out for a long drive, no smoke. That night I tried to go to Blockbuster to get a movie, she started smoking like crazy.

I am stuck, not familiar with the nikki carb, don't know how to troubleshoot this problem. Could it be the carb, the choke that stays close and sucks the oil, vacum leak, or the metering pump?

Car has original factory setup, original engine with 135k miles, no aftermarket parts.

Need help please.

Kentetsu · 06-11-2008, 08:12 PM

Check your oil level, make sure you didn't overfill it. If the situation is due to bad oil control rings, you might be able to get by with the use of Lucas Heavy Duty Oil Stabilizer. I used that in my old motor for a couple of years, because without it I would throw a smoke screen like James Bond only better.

Sterling · 06-12-2008, 06:40 PM

What weight did you use, Kentetsu?

Kentetsu · 06-13-2008, 05:03 AM

I used 20/50 Castrol GTX, along with about 1 quart of the Lucas. After that, the only time it would smoke was at races when I would be decelerating from redline or higher. You can see it in some of my videos, and its not much.

What happened was, I used the Haynes manual to find out how much oil for an oil change. The information provided was incorrect (had to look in the back section for updated information to get the correct amount), and as a result I overfilled the system. Everything was fine for a few miles, then I let off the gas to catch my off ramp and all of a sudden I couldn't see anything behind me. The entire freeway had to slow down until the smoke blew off the road.

So, in my experience, overfilling the crankcase will blow out the oil control rings in very short order.

But still, I got another good 20k miles out of her like that thanks to the Lucas...

1988rx7 · 06-13-2008, 08:44 AM

Kentetsu,

First of all thanks for the reply.

As far as oil amount, I used 4 quarts of Castrol GTX 20W50.
Then changed the oil to 10W40 thinking it was too thick. But I had the same results. The problem is intermittent, in one occation as I was ready to go home from work and I started the car with the choke, she started fine no smoke, but I didn't get to the corner when she started smoking. I pulled to the side and turned the car off. I opened the hood and played with the oil metering rod, pushing it up and down several times. Closed the hood and started the car, and believe it or not when I started the car, she smoked while she cleared the engine for about a minute and then no smoke, got home with no problems.
I will try this weekend using the 1 quart of Lucas Heavy Duty Oil Stabilizer and 3 quarts of 20W50 Castrol GTX.
I'll let you know how it goes.
If the oil rings are bad, wouldn't I feel loss in power?
She feels strong as ever.

Jeff20B · 06-13-2008, 01:23 PM

You wouldn't feel a loss of power because the oil seals don't seal compression; that is to say they were not designed specifically for that purpose, as the side, corner and apex seals were. The oil seals are oil scrapers with a sharp edge and a sealling o-ring with, held against the side plate by a long wavy spring under each one. You can purchase competition outer springs which apply a little more pressure; I like to use them on boosted engines because, as I said earlier, they weren't really designed to hold compression, but what sealing they do do, helps keep some of the boost from leaking inside the sump area of the engine, and therefore there is more available to make power.

Just bite the bullet and rebuild your engine. Sounds like you need new o-rings and possibly new oil seals too. Band-aid fixes only work for so long.

Kentetsu · 06-14-2008, 10:19 PM

I forgot to ask what the smoke smells like... I guess I may have jumped to a conclusion since you mentioned the oil change.

Does the smoke smell like burnt oil? Gas? Coolant?

1988rx7 · 06-16-2008, 04:26 PM

Kentetsu,

It smells like burned oil. Its not coolant nor gas.

Bought the Lucas Oil stabilizer but didn't egt to try it yet.

Will keep you posted.

Thanks

BigTeddy · 11-20-2008, 06:05 PM

More then likely its your oil control rings not working properly or on there way out, and only working when they want to...

Assuming that you have an old motor with no rebuild, 20/50 was the way to go, even on the new motors i build for myself or my customers i still use 20/50 weight for the all around assurance of knowing im getting good lube...And on older motors with high miles and wear and tear on them having a weight that high is crucial in sparing more miles out of them...

Let us know what happens

teddy

06-11-2008, 09:34 AM	#1
1988rx7 1988rx7 Join Date: Jun 2008 Posts: 5 Rep Power: 0	Heavy Smoking 1979 RX7 Hi, I am new to site. I owned a 1988 rx7 convertible for about 7 years, but last year she was killed by a little old lady. Now I own a 1979 Rx7 that I am restoring. I got her painted, did the interior, changed the dash, she is almost ready... But now I have a Big problem. She started smoking alot, I changed the oil one day and the next driving down the highway she began smoking so much I couldn't see the car behind me. I parked the car thinking I broke an oil seal. Talking to a friend was told that maybe the rod from the carb to oil metering pump got stuck and was letting the pump inject lots of oil into carb, hence the heavy smoke. Have verify the rod and its not stuck, when even further to lubricte with silicone that area. After a week of the car sitting, I tried starting her, and she worked no smoke. Took her out for a long drive, no smoke. That night I tried to go to Blockbuster to get a movie, she started smoking like crazy. I am stuck, not familiar with the nikki carb, don't know how to troubleshoot this problem. Could it be the carb, the choke that stays close and sucks the oil, vacum leak, or the metering pump? Car has original factory setup, original engine with 135k miles, no aftermarket parts. Need help please.

06-11-2008, 08:12 PM	#2
Kentetsu RCC Contributor Join Date: Feb 2008 Location: Grand Rapids, Michigan Posts: 530 Rep Power: 18	Check your oil level, make sure you didn't overfill it. If the situation is due to bad oil control rings, you might be able to get by with the use of Lucas Heavy Duty Oil Stabilizer. I used that in my old motor for a couple of years, because without it I would throw a smoke screen like James Bond only better. __________________ "Learn from the past, or it will become your future...." '85 GS 12a + LSD/Sterling carb/Respeed coilovers/Respeed front swaybar/Respeed adj. rear spring perches/Illuminas/Bilsteins on rear AutoX vids @ http://www.youtube.com/user/Kentetsu1

06-13-2008, 05:03 AM	#4
Kentetsu RCC Contributor Join Date: Feb 2008 Location: Grand Rapids, Michigan Posts: 530 Rep Power: 18	I used 20/50 Castrol GTX, along with about 1 quart of the Lucas. After that, the only time it would smoke was at races when I would be decelerating from redline or higher. You can see it in some of my videos, and its not much. What happened was, I used the Haynes manual to find out how much oil for an oil change. The information provided was incorrect (had to look in the back section for updated information to get the correct amount), and as a result I overfilled the system. Everything was fine for a few miles, then I let off the gas to catch my off ramp and all of a sudden I couldn't see anything behind me. The entire freeway had to slow down until the smoke blew off the road. So, in my experience, overfilling the crankcase will blow out the oil control rings in very short order. But still, I got another good 20k miles out of her like that thanks to the Lucas... __________________ "Learn from the past, or it will become your future...." '85 GS 12a + LSD/Sterling carb/Respeed coilovers/Respeed front swaybar/Respeed adj. rear spring perches/Illuminas/Bilsteins on rear AutoX vids @ http://www.youtube.com/user/Kentetsu1

11-20-2008, 06:05 PM	#9
BigTeddy Rotary Fan in Training Join Date: Sep 2008 Posts: 46 Rep Power: 0	More then likely its your oil control rings not working properly or on there way out, and only working when they want to... Assuming that you have an old motor with no rebuild, 20/50 was the way to go, even on the new motors i build for myself or my customers i still use 20/50 weight for the all around assurance of knowing im getting good lube...And on older motors with high miles and wear and tear on them having a weight that high is crucial in sparing more miles out of them... Let us know what happens teddy __________________ One Turbo At A Time

06-12-2008, 06:40 PM	#3
Sterling Premium Vendor Join Date: Feb 2008 Posts: 74 Rep Power: 18	What weight did you use, Kentetsu?

06-13-2008, 08:44 AM	#5
1988rx7 1988rx7 Join Date: Jun 2008 Posts: 5 Rep Power: 0	Kentetsu, First of all thanks for the reply. As far as oil amount, I used 4 quarts of Castrol GTX 20W50. Then changed the oil to 10W40 thinking it was too thick. But I had the same results. The problem is intermittent, in one occation as I was ready to go home from work and I started the car with the choke, she started fine no smoke, but I didn't get to the corner when she started smoking. I pulled to the side and turned the car off. I opened the hood and played with the oil metering rod, pushing it up and down several times. Closed the hood and started the car, and believe it or not when I started the car, she smoked while she cleared the engine for about a minute and then no smoke, got home with no problems. I will try this weekend using the 1 quart of Lucas Heavy Duty Oil Stabilizer and 3 quarts of 20W50 Castrol GTX. I'll let you know how it goes. If the oil rings are bad, wouldn't I feel loss in power? She feels strong as ever.

06-13-2008, 01:23 PM	#6
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	You wouldn't feel a loss of power because the oil seals don't seal compression; that is to say they were not designed specifically for that purpose, as the side, corner and apex seals were. The oil seals are oil scrapers with a sharp edge and a sealling o-ring with, held against the side plate by a long wavy spring under each one. You can purchase competition outer springs which apply a little more pressure; I like to use them on boosted engines because, as I said earlier, they weren't really designed to hold compression, but what sealing they do do, helps keep some of the boost from leaking inside the sump area of the engine, and therefore there is more available to make power. Just bite the bullet and rebuild your engine. Sounds like you need new o-rings and possibly new oil seals too. Band-aid fixes only work for so long.

06-14-2008, 10:19 PM	#7
Kentetsu RCC Contributor Join Date: Feb 2008 Location: Grand Rapids, Michigan Posts: 530 Rep Power: 18	I forgot to ask what the smoke smells like... I guess I may have jumped to a conclusion since you mentioned the oil change. Does the smoke smell like burnt oil? Gas? Coolant?

06-16-2008, 04:26 PM	#8
1988rx7 1988rx7 Join Date: Jun 2008 Posts: 5 Rep Power: 0	Kentetsu, It smells like burned oil. Its not coolant nor gas. Bought the Lucas Oil stabilizer but didn't egt to try it yet. Will keep you posted. Thanks