Pete187Rock

Hows it goin folks, i just purchased a 1990 RX7 vert 1.3L non turbo and so far my issues are as follows:
Thermostat housing leaking at neck
White smoke at WOT
check engine light at decel
TPS code 12 stored in computer
When A/C is on idle gets erratic but idles fine with it off


Any help with this would greatly be appreciated, thanks

iceblue

Pull it apart and replace gasket or use RTV
Are you sure it does not have a bluish tint? I am going with oil being burned over a coolant seal. What year is the car? And how is the tune up and oil situation? Could be a warn side seal, something wrong with OMP, or coolant seal. Use a coolant compression tester to verify that it holds a 13psi.
I do not know
http://fc3spro.com/TECH/HOWTO/TPS/tps.html
Clean your BACV valve

WonkoTheSane

iTrader: (2)

Is the smoke only after you let off of your throttle at WOT? I know that all rotaries I"ve seen have a bit of white smoke if you're flooring it then let of quickly (Like when racing), its due to it injecting enough oil for high RPM, but then your RPMs drop faster than your OMP's injection rate.

In addition to IceBlue's idea of a coolant pressure test, i'd recommend getting a regular engine compression check done, that's the easist way to tell if there's something critically wrong with the engine.

Listen to IceBlue for the rest

Pete187Rock

WEll when i say the neck of the housing is leaking its leaking where the previous owner tried to jb weld it up the middle. I think it needs replacing and cannot find one for less than 80 bucks.

The smoke seems to be mostly white though it may have a blueish tint to it its hard to say. Its weird though sometimes it does it at WOT, sometimes it does it at decel but mostly after i WOT for a bit. I had a hard time getting about 5k but i sprayed some CC in the TB and it helped alot now it gets to around 7k but still seems like it doesnt want to pull hard past that.

What is a BACV valve? Im a mechanic of 8 years but ive never messed with Rotaries before.

When i drive it to work tommorrow ill see if i can distinguish the color of the smoke, since its been raining its hard to tell through the window tint.

If you know anyone who has a thermostat housing for this i really need it, my add coolat light came on as i was leaving work today. I have seen the leak and it looks like a little water gun squirting water out of the side of the housing itself. Thanks for the help by the way.

WonkoTheSane

iTrader: (2)

hmm.. Check the compression of the engine, and get back to us..

As far as finding a water pump/thermostat housing, you should be able to pick one up really cheap.. just check the "for sale" section of this forum. it's on the main page.

The BAC valve is basically an "idle controller".. it sorta deals with maintaining a good idle when a sudden load kicks in (Like when you turn your AC on). It's on the throttlebody.. Just look in the Factory Service Manual.

What!? You don't have a factory service manual? Well, you need to check out the FAQs at the top of this section, it has a link where you can download the entire FSM for free.

Good luck

Pete187Rock

Sweet info man, thanks.

Pete187Rock

Also would like to know if i did bad on this deal. So far i got about 2500 in this car. Has new convertible top, A/c Blows cold, new tries, brakes, car runs good but has the problems listed above.

WonkoTheSane

iTrader: (2)

sounds fine to me.. If you have low compression, you're may be in for an engine rebuild/swap. If you don't have low compression, its probably an oil seal going, and there's a lot of people that drive for a while with that happening, just keep an eye on your oil pressure gauge. As long as the body's straight, and you're happy with it, then you made a good deal

I'd guess that you're in for less than 75 bucks to fix everything listed above, if you use the "for sale" section and buy used stuff. (assuming the engine internals are in good shape).

Pete187Rock

OK did the drive to work this morning and theres absolutely no smoke on start up, which im considering is a good thing. However, if you drive it easy say below 3500 rpm , it doesnt seem to smoke at all, but, when you play a bit and get the rpms up, this is when the smoke starts. Its mostly a white smoke but if it has a bluish tint to it its really faint. After about 2 or 3 minutes of driving it hard it all goes away and it wont do it again till i let it sit and get cold. Changed the oil today and put 15/50 mobil 1 synthetic in it and it seems to like it alot.
So judging by my description of the smoke what could it be? AM i lookin to rebuild this thing or not.

iceblue

^ without compression numbers cant say. But i would not think so for a little time atleast. Perhaps it is just starting to get a little tierd nothing major. Maybe they had a very light oil in and causing it to leak past the oil seals.

Pete187Rock

Yeah but this much smoke almost caused me to get pulled over today when i really hit it good. Do you think once i get the tps right and the thermostat housing fixed that this may help with the issues with the smoke? I wanna try something tommorrow, im gonna baby it for about 15 minutes and then rip on it some and see if it still smokes. Its almost like it collects somewhere after it sits and when you really gun it, it releases what has collected. Where it is collecting i have no clue because ive never messed with Rotaries. I couldnt even explain how they work yet but im learning about them. IF this was a 3.4.6. or 8 cylinder or a motorcycle i could tell you exactly whats goin on but never messed with the Rotary motors.

iceblue

That much smoke ehh :-/, Bad oil seals. When the car is sitting it seaps past the side apex seals laying oil into the combustion chamber and buring off, under high accel greater oil pressure is creating pushing past the side seals, burning it off. Requires a rebuild to fix sorry. My word of the internet I would not go soly on best bet is to ask a local rotary macanich to see it as I or "we" can not see the smoking.

Maybe this will help you.


Have a coolant pressure test done I am sure you have one being a seasond mecanich and see if it holds 13PSI. If not and tere is no external leaks more or less the car has ben over heated, leaking coolant into the combustion chamber. This can cause rust on the side irons and cause premature ware of side seals as well under server cases warping the motors. If this happend a rebuild may not be possible do to the warped internals. A new block will be required.

Pete187Rock

IF it was leaking coolant that bad wouldnt it be smoking all the time not just for the initial run and go away?

WonkoTheSane

iTrader: (2)

not always, it may be just leaking in when things are cooling down, and contracting.

any way to get us a video of this?

and just to be a nag, have you done a compression check yet?

Pete187Rock

Havent gotten around to getting video of it or done the compression test or the TPS configuration. I work almost 12 hours a day so when i get a slow chance at work i tinker with it but not much. I drove it to work this morning and drove it moderately but just moderate throttle to about 5k shifting for about 5 minutes. After that i decided to dog it a bit and what would you know, no smoke at all. I think the gaskets or o rings or whatever is leaking oil or coolant expands and seals once the motor gets warm. When its cold its not quite amking a good seal. Just my theory.

Pete187Rock

bump

Pete187Rock

Im planning on selling this car but after owning a rotary i plan on getting a newer version, one that i dont have to work on as much.

WonkoTheSane

iTrader: (2)

Um.. I don't think you've planned that one out too well... The 91 is the last year of the 2nd Generation Rx-7.. That means that you can only trade up one year. 93-95 are the only years that they brought the 3rd gen to America.. and if you think getting a 3rd gen will be more reliable, you definately want to wonder over to that section of the forum.

Pete187Rock

Well i was thinking more along the lines of the new RX8.

iceblue

That is like comparing ice skating to hocky. I own both cars and love them both but a different game they are.

Pete187Rock

Well right now i dont have alot of free time since i am a Novice Roadracer and work more than full time as a mechanic. ITs all i can do to get my bills paid down so i can go full out next season. I guess its just having something newer that you dont really have to bother with as much is what i meant. I love the second gen RX7 and i wish i had time to tinker with it.

full-cruise

iTrader: (5)

beating on it isnt going to make matters better youll just end up with more smoke then your starting out with. i have a coolent neck from a S4 if your looking for one still. i can send it to you what i paid for it + shipping. pm me if your interested

Pete187Rock

How much and will it work on my 90 RX7 1.3L non turbo? Send a pic to r1o8c7k@comcast.net if you can.