mikexj1020

I know there are many idle and carb threads on here I really just want to know if this seems like a vacuum leak or needs a carb rebuild. and Why is my engine Steaming/Smoking

Car: 1985 Rx7. Sat for 12 years. Now has New: Fuel pump, fuel filter, tank boiled and sealed, clutch master & slave, cap, rotor, plugs, wires, New radiator, new brakes and battery all fluids and oils changed.

After fuel pump, filter and tank boiled. All I had to do was turn up idle a little and she idled and ran great. Car wasnt run much for a month or so, Did radiator and now its runs like this and the engine steams. ...and yes she doesnt overheat and i added antifreeze.


This is Engine with choke on, warming up running at 3000 RPM.
Runs pretty strong, but seems to have misfiring condition
http://www.youtube.com/watch?v=_IbIueGvOAI

After engine warm up, it stalls out because of lean, but engine Steams/Smokes.
It smells like antifreeze and is coming from the middle of the engine. I do not see and pooling or leaking on my driveway.
http://www.youtube.com/watch?v=7g51L-c23UI

This is after Warmup/Choke disengages. Engine runs lean ans stalls.
Will continue to run with foot on and but wants to die, Engine will rev to rev limiter though. Does this seem like a vacuum leak or carb rebuild. She ran pretty decent a month or a so ago. But this car has sat for 12 years.
http://www.youtube.com/watch?v=mhpmPr2HVng

Thanks for all your help

RotaryEvolution

iTrader: (30)

probably dry rotted lower intake to block gasket, may be due for a carb rebuild as well.

rent a pressure tester from a local auto parts store, remove the air filter assembly and pressurize the system to see if you can pinpoint where the coolant is leaking from.

mikexj1020

Okay thanks, I will look into the intake manifold Gasket. Do you think that is for the rough idle or for the steaming antifreeze leak

For an 85 12a would the first on posted on this site be the one I need.
http://www.mazdatrix.com/c-2.htm

john smack

iTrader: (12)

You will want to replace the o-rings as well as the gasket... and yes the first one is what you need

mikexj1020

Okay. I know you all prolly think I am a super noob with these questions but the O-Rings are the 11th picture down from http://www.mazdatrix.com/c-2.htm which leads to this link http://www.mazdatrix.com/getprice.as...m=13-1130-8527

Pinpointing problems and finding the correct parts is not always my strong suit, wrenching however I am decent with. I am pretty good understanding but Rotarys are a different beast.

Im gonna get a propane torch tank and test for vacuum leaks and get the cooling system pressure tester as well. This will all be on Wednesday and Friday I will keep this forum posted. Anymore info would be great.

Thanks guys

Kentetsu

Yeah, if you're getting steam off the motor itself, check the O rings between the block and the intake manifold.

As far as the idle issues, there are two adjustments: the idle speed, and the idle mixture. Turn up the idle speed until the car will stay running, then adjust the idle mixture until it runs smoothly. Your idle speed will probably be way too high at this point, so now you turn down the idle speed a bit, and readjust the idle mixture to smooth it out again. Just keep doing this until you get to where you want to be (700 - 1000).




.

mikexj1020

The Idle Mixture screw has that anti tamper cap on it. I heard that in order to remove this cap the carburetor needs to be removed

Kentetsu

www.sterlingmetalworks.com Lots of info on these carbs, including an adjustment procedure.

RX-7 Chris

iTrader: (19)

It is a little hard to remove the cap with the carb in but it can be done. You will have to remove the carb anyway though to replace the gasket and o-rings.

You shouldn't have the adjust the mixture if it has never been messed with.

mikexj1020

Okay, well I still need to rule out the The intake leak with the coolant pressure test. Could be possible that there's a vacuum leak at the intake too. The car was running good a month ago and wasnt being ran. It never idled this rough. I'm getting a propane tank in there this weekend and spray it around the intake

boyee

iTrader: (3)

check your air control valve too. there could be an internal vacuum leak. you can swap it with another used known working one. if you can, remove the hose that goes from the acv to the air filter assembly and try to get the engine rpm to be at 2500 rpm or below and you should not feel any air coming out of that hose. when you rev the engine though, air will come out but after you stabilize the revs, air should not come out at 2500 or below rpms. any rpms higher air will flow out of that hose.

also with the choke pulled out, it shouldnt be at 3000 rpms. that is way too high. the choke idle speed normally is around 1000-2000 rpms depending where the cable is set at as well as how far you pull out your choke rod.

also check your timing.

thanks for posting the videos. they turned out really good and helps us troubleshoot as well

74RX4

iTrader: (10)

If your car sat for 12 years the carb needs to be rebuilt. Sounds like you might have a vacuum leak. Check this hose if you still have emission control devices installed.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/hose-question-750125/

mikexj1020

Okay this is all good info thanks guys I wanna start these test on the car but the weened just can't come soon enough.

@74RX4 I did check that hose b.c I've seen that post before but I think I will go over it again.

mikexj1020

So for an update:

- I did a pressure test on coolant system And held pressure for 10minutes at 10psi.
- The smoking I beleive is the oil leaking by the bottom of the engine onto exhaust manifold. After running engine for extended period of time smoke went away. Went out next morning instead of waiting a week to restart the engine. There was no smoke.

- I have been researching and building my confidence in rebuilding the carb. I hosed the engine down with starting fluid and the idle never raised, also used propane tank but it didn't seem to work.

Do you all think if I were to remove the rats nest that I may solve my problem. Or should I just rebuild the carb and hook all emissions/rats nest stuff back up.

Thanks for input

mikexj1020

Last Week I took the car for a spin up and down the block trying to not take my foot off the gas from having it stall. I realized I didnt have my wipers hooked up and i turned right around. Then tried to see how low I could get the idle to be with my foot on the gas. It stalled like 4 times in a row when trying and now the car wont start. Figgured it was flooded, waited a few days, clean the plugs, cranked it with no plugs and disconnected the FP. Reconnected everything and now the car does not run at all, only runs a bit with starting fluid. Gas does shoot into the carb but does not run. Time for a rebuild.

Kentetsu

Verify that your ignition system is functioning correctly. You could be describing a carb issue, or a loss of leading ignition. Ignition is a lot easier to check, so I'd start there.

mikexj1020

So I know not many people have followed this thread but I still think its worth an update and you will ALL get a laugh out of this one...

So a few months ago, the car ran good and Idled stong.
Then the car would idle very lean and stall but still rev up to rev limiter with full power.
Then the car completely stopped running.

So I figured that the carb was shot and needed a total rebuid. I got the carb rebuild kit. Read sterling metal works and other write ups over and over. I removed the carb from the car and right before I was gonna tear into it I decided to check the fuel pump. The pump had low pressure.
...I removed the FP and tested it with one end in a container of gas and the other into an empty container so it would catch the fuel. The fuel pump is operating functionally. So my next thought, was clogged fuel line or no fuel in tank. I ADDED FUEL TO THE TANK AND PROBLEM SOLVED. Oops, forgot to add gas to it. (I shoulda watched Sling Blade "Aint got no gas in it")

So i put the carb back on and hooked everything up (I also replaced just about all of the vacuum lines while I was at it. I got the car running again but it went back to poor idle but revs high and drives okay with foot on gas. I turned the idle screw up a little bit more, and NOW she idles. She idles very lean and sometimes stalls but still idles. The idle is around 1000 RPM. She runs great down the road. I think i need to adjust mixture screw or still may need rebuild.

Check video

http://www.youtube.com/watch?v=rDV2E1muYFY