|
Carburetors and Carb Tuning.. All info about old school carb set ups.. |
Welcome to Rotary Car Club. You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today! If you have any problems with the registration process or your account login, please contact contact us. |
|
Thread Tools | Display Modes |
06-11-2008, 09:34 AM | #1 |
1988rx7
|
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 |
RCC Contributor
|
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 |
RCC Contributor
|
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 |
06-13-2008, 08:44 AM | #5 |
1988rx7
|
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 |
Rotary Fanatic
|
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 |
RCC Contributor
|
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? |
11-20-2008, 06:05 PM | #9 |
Rotary Fan in Training
|
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 |