1979 RX7 problems
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1979 RX7 problems
I just got my 79 RX7 shipped to me finally from Ca. It starts up good and easy with the choke and eventually warms up OK and idles. It seems to have decent power towards midrange. It smokes like a train when you rev it up though. All of the ignition parts have been replaced and the dwell is accurate. I have some charging system problems too that I cannot figure out it has a new alternator and regulator. The wiring looks fine but when its running the check oil level, coolant level, and charge lights are all on and it doesnt seem to be charging. Also the tach is stuck at 4000 whenever the key is turned on and its not accurate when running just off idle it says like 6000 rpm. It holds pressure with the cooling system pressure tester and it doesnt run hot. Is there any way to check why the engine smokes when revved up? also has anyone experienced charging problems like this? I just wanna be able to drive it.
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first of all, welcome to the forum! Tip #1 (which you would hear soon anyway), read Trochoid's signature for the FSMs!
Well, whatever you do, don't run it low on oil/coolant. Top them off first. Then, monitor their consumption. Like Jeff said, the most likely cause of the smoke is coolant getting into the the chamber through worn side seals. What color is the smoke? White would be coolant. If it's a slow consumption of coolant, you can run it like this for a long time without a rebuild provided you do regular coolant flushes.
Do a compression test. If it passes, there's also a kit called a "Universal Combustion Leak Test" or something like that. What is does is test the coolant to see if combustion residue has gotten into it.
Charging issues could just be that you need a new battery, load test it.
I think I have an idea what you're talking about with all the lights being on/tach being stuck in voltmeter mode, like the car doesn't realize it's been started. My car did this a couple times somewhat recently but it snapped out of it right away... So I don't really know cause I never fixed it, though I think (at least in my case) it's a relay getting stuck. Look at the FSMs to figure out which one!
Well, whatever you do, don't run it low on oil/coolant. Top them off first. Then, monitor their consumption. Like Jeff said, the most likely cause of the smoke is coolant getting into the the chamber through worn side seals. What color is the smoke? White would be coolant. If it's a slow consumption of coolant, you can run it like this for a long time without a rebuild provided you do regular coolant flushes.
Do a compression test. If it passes, there's also a kit called a "Universal Combustion Leak Test" or something like that. What is does is test the coolant to see if combustion residue has gotten into it.
Charging issues could just be that you need a new battery, load test it.
I think I have an idea what you're talking about with all the lights being on/tach being stuck in voltmeter mode, like the car doesn't realize it's been started. My car did this a couple times somewhat recently but it snapped out of it right away... So I don't really know cause I never fixed it, though I think (at least in my case) it's a relay getting stuck. Look at the FSMs to figure out which one!
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I know this is an old thread... but just in case anyone looks over this...
The 1979's have an EXTERNAL Regulator.. its a small box on the left side the car and is about $120 bucks. I had the problem with the tac up at 5000 when the key was turned over and a few other electrical problems... replaced the regulator and it fixed everything. Just FYI
The 1979's have an EXTERNAL Regulator.. its a small box on the left side the car and is about $120 bucks. I had the problem with the tac up at 5000 when the key was turned over and a few other electrical problems... replaced the regulator and it fixed everything. Just FYI
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79 rx7 no charge
I just read your post you made about externally regulated rx7. The OE regulator on mine seemed to have a burnt wire. So I replaced it. That didnt work, so I bought an alternator. same problem, the battery is new, so I bought a Standard regulator. That didnt work. I have a feeling I need an OE regulator but I have no definitive charging system schematic. Any help would be greatly appreciated. I have a 79 CA model.
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no charging
I changed the oil with 20w50 and drove it around. It doesnt smoke too much when it is warmed up but it doesnt warm up fully because I am pretty sure the thermostat is stuck open. The smoke seems to be mostly oil and fuel. it doesnt seem to use any coolant. It has the Nikki 4bbl with the rats nest fully intact. Does anyone on here know these old 4bbls well? I have 2 extra 4bbls for this and a carb kit. I would like to simplify this induction system. I might try to change the thermostat tomorrow but I am SOL until I can get this darn thing to charge. Does anyone have a charging system test procedure for this? I am very close to just converting it to electronic ignition and solid state internal reg alternator. Before I attempt tearing into the engine I would like it to at least charge. The car doesnt idle either I believe the pilots in the carb are probably plugged up from sitting. Feel free to send me PMs or emails I need lots of advice. I am an ASE master L1 auto technician but I don't know much about these cars.
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The electrical part sounds like classic RX-7 Alternator (or regulator) problem.
as for smoke, If the car was stored in cold temps during shipping the coolant may have frozen and distorted some seals and joints to cause leaks. Rather than a heavier oil, which may not help and may reduce oiling quality, you might try Lucas Oil Stabilizer, which a couple guys here (but not me) have tried successfully.
as for smoke, If the car was stored in cold temps during shipping the coolant may have frozen and distorted some seals and joints to cause leaks. Rather than a heavier oil, which may not help and may reduce oiling quality, you might try Lucas Oil Stabilizer, which a couple guys here (but not me) have tried successfully.
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Ya so I am going to pickup where I left off with this. I converted the alternator to the solid state one. I still need to run a switched lead to it but would like to do this through the factory wiring. I found a SMOKING deal on 225/60/13 tires so I am going to pull it out of the hole tomorrow and work on the carburetor. It looks like there is an oil leak near the oil injection assembly.
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I tried to get the Rx7 started today and it doesn't seem to be getting much fuel. Do I have to completely tear down the carb to clean out the jets or is most of it accessible leaving it on the car? It won't stay running. Have to pump the pedal constantly to keep it running.
#17
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Sounds like its time for a carb rebuild. Its not expensive and not hard to do on the Nikki. Just make sure you get a good kit like the GP Sorensen kit that comes with aluminum crush washers instead of fiber washers for the banjo bolts like in other lesser kits. The Nikki is really not any different from any other carb so if you have experience with others the Nikki should be no problem. Its well worth the $25-$30 for the rebuild kit and about 3-4 hours of your time to clean it up real good.
Also, if you search the 1st gen forum, I posted a thread on converting the 79's externally regulated alternator to an internally regulated one, dealing with the electrical side of things. I didn't particularly like the thread about this in the archives since when I did it that way I didn't retain the stock function of the voltmeter/dash light. My thread is a full conversion replicating the function of the external regulator in relation to the dash functions.
Also, if you search the 1st gen forum, I posted a thread on converting the 79's externally regulated alternator to an internally regulated one, dealing with the electrical side of things. I didn't particularly like the thread about this in the archives since when I did it that way I didn't retain the stock function of the voltmeter/dash light. My thread is a full conversion replicating the function of the external regulator in relation to the dash functions.
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Cool I bought a KEM carb kit a few years ago. I have a couple of spare nikki 4 barrels so I may just rebuild one of them and then put it on. I would like to eliminate as much of the emission controls on the carb. I want to retain the stock lights and the choke however.
85rotarypower do you have a link to that thread? I put in an internally regulated alternator but haven't permanently wired it up yet. I would like to get the voltmeter function to work.
85rotarypower do you have a link to that thread? I put in an internally regulated alternator but haven't permanently wired it up yet. I would like to get the voltmeter function to work.
#19
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Here is a link to the thread. https://www.rx7club.com/1st-generation-specific-1979-1985-18/how-1979-alternator-upgrade-967330/
I think I've included all the required information in that thread. Hope it works out for you and if you have any questions, feel free to ask.
I think I've included all the required information in that thread. Hope it works out for you and if you have any questions, feel free to ask.
#21
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Just FYI but a Nissan Frontier alternator will work fine in place of the stock alternator. The Blg wire in the external regulator is where you need to attach the alternator regulator wire for the internally regulated alternators. Just got done with that **** festival on my 7 today.
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Just FYI but a Nissan Frontier alternator will work fine in place of the stock alternator. The Blg wire in the external regulator is where you need to attach the alternator regulator wire for the internally regulated alternators. Just got done with that **** festival on my 7 today.
how many wire is it?
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