bahlorm

the 85 rx7 is the first car I have had with a carburetor. I know they are not as easy to start as fuel injected but this is just crazy. Weather if the engine is already warm or not, it takes around 3 minutes to start this thing when its around 60 degrees outside. When the engine is cold it takes close to 5 or 10 minutes and I have to use starting fluid almost every time. I just went outside to start the car and I pulled out the choke sprayed starting fluid in the car and gave it a little gas when it got close to starting. It almost got it once or twice but the battery died before the car would even start! I have given this car a tuneup and I get spark, I am getting fuel, I am just not getting a good fire without it taking a long *** time every time I shut the car off. What could be going on with it? And I am also wondering if this also could have to do with timing since I had a post earlier wondering if my car may be out of time. Which I was going to check this morning, but I couldn't get it started and don't have time to charge the battery and do everything before work.

Mr_Miles

iTrader: (1)

mine starts with barely two turns hot or cold. maybe your timing is wrong. I had a ford that would do what you're describing when it was hot and it turned out to be timing.

how does it run when it does start? does it get really hot? does it chug?

ray green

iTrader: (14)

Obviously there is something wrong, the car should start right up whether hot or cold.

Have you checked for vacuum leaks? Are your plugs clean and dry, not fouled with gas or oil?

Some patience and systematic checking will solve the problem(s), which is (are) probably not too serious. It just seems that way when the car isn't running.

bahlorm

The plugs are brand new. I just got them 2 days ago. And the car doesn't really have the power I thought it would and when I am not on the gas it jerks just a little bit. Also when I am idling and I get on the gas real hard it acts as if it will stall and then it will take off. But during acceleration and driving at a constant speed other than a lack of power it drives good.

t_g_farrell

iTrader: (1)

I think in another thread you stated this car had been sitting for a few years and
you were having other issues with its performance. Let me clue you in, you have a
30 year old car that needs every piece of rubber replaced, all fluids changed and
all wear items inspected/refreshed. I mean hoses, spark plugs, brakes, anything
thats a wear item. You also have 30 year old wiring that may have issues especially
with grounds and such.

My advice to you is to have about $1000.00 set aside to throw at this thing. Put it
up on jackstands and go thru one subsystem at a time until your done. Then
make sure its adjusted and timed correctly and see how it runs. Even after all of this
don't expect it to be a steady DD because you'll have other issues popup
randomly until its all sorted.

I don't want to come off as being mean here but the reality is that this car will need
a lot of TLC to get it to a state of stability. From your post it sounds like you have a
different expectation.

RX-7 Chris

iTrader: (19)

I agree with tg completely. I dumped about $1500 into my new car before is was a good DD and I still have a few things I need to do

Kentetsu

I was having a very tough time starting mine this spring. Finally it flooded so bad that it was down for two days. Even though I had spark on the leading ignition, I had eliminated every other factor I could think of so I threw in a 2nd gen coil pack. Fired right up as soon as I touched the key.

I had always thought that if you confirmed that you had spark, you could move on. But apparently there is spark, and then there is SPARK. So you might consider this mod.

Also, after shutting the car off, pull the air filter off and see if you have fuel dribbling into the carb barrels...




.

DivinDriver

iTrader: (15)

Properly tuned with a stock set-up, a cold start consists of:

1) turn the key to on and pull the choke
2) if the car's been parked for a couple weeks, give the pump about 10 secs to fill the lines and bowls (I can hear the pump sound change when the floats close)
3) turn the key to start; within less than 5 secs it'll be fired up and running at high idle

A hot start consists of turning the key and waiting a second or so.

No need to touch the gas pedal IF you have everything hooked up and working, in either case.

kutukutu1

iTrader: (5)

a properly tuned carb, and correct timing will get the car started hot or cold, mine does not have a choke or anything and even at 20 F it will start on the second crank. if its cold i always pump it 3 times then crank. but i am sure its poor carb tuning.

bahlorm

I am pretty sure it is timing. I advanced the timing a little and it started a little bit easier and it gave this car a **** load more power than it had. It is still just not timed correctly. In the morning I will be bringing out the timing light and setting it right and see how well this thing fires. I also noticed that the car is so hard to start because it is flooding itself when it is shut off. Last night it got to the point to where it would not start and I had to take out the plugs and unflood it, and right after I did that the car fired up perfectly.

Kentetsu

Did you perform the check I requested (see post above)?

bahlorm

I have found out that when the car is shut off gas is still leaking into the carburetor and causing it to flood itself. I am getting a rebuild kit this weekend and I will try and get it done, and hope I don't screw something up lol.

Kentetsu

Possible causes of your issue (fuel entering barrels after shutdown) off the top of my head:

1. Return line restrictor missing or installed backwards.
2. Float bowl solenoid faulty or disconnected.
3. Gas tank venting issues.
4. Charcoal cannister lines obstructed.
5. Float level too high.

Might be a few more, but those are the ones I can recall encountering. A carb rebuild will not address any of them, but they are all fairly simple to check and cheap/free to fix.

smellycat

Mine did the same thing when I got it. Carb is gunked up. Floats are not working ... stuck open. $20 kit 6-7 hours Vrooomm

bahlorm

How do you check the float?

I just used my donor carb to see if I could even find out how to get to the float. I was actually surprised at how easy it was, and the bowl is covered in rust. I also have a feeling that most likely the one on the car right now is the same way after sitting for so long and one of these came from a junk yard and were supposed to be rebuilt.

Do you have to have the car on to find out? I have been told from a few people that there is a possibility that they probably aren't working correctly since the car was sitting for a year and a half to begin with. I just figured it was in need of a rebuild though.

Kentetsu

You can check the float function by observing the level of fuel in the float bowls. There is a small window on the front and back, fuel should be at the halfway point.

t_g_farrell

iTrader: (1)

Not to be a broken record, but your going to have to go thru each system and
clean and refurbish it all or it will constantly be giving you issues as you stumble
into the next area that needs attention.

bahlorm

Yeah I understand that but working with a budget and a limited amount of time I just have to do things one at a time to get this thing running well. For the moment preventing it from flooding itself is the main thing I am working on.

smellycat

I'm with you on a budget. If the floats are stuck open you will flood oz's down the intake. Mine was pouring gas and it would puddle on top of the butter fly till i tapped the throttle. I poured a bottle of marvel mystery oil in the gas tank. hoping it would clean up the carb. Maybe that will work.

One Idea . Fill up the floats in the carb. then unplug the fuel pump under the compartment behind back seat. it should run a long time just off the float chamber
If that makes it run. you know everything is good except the gunked up Carb

bahlorm

Okay I will try that tomorrow. I plan to take this carb apart and clean it out the best I can. I just don't know exactly what really needs to be clean other than I already plan to clean the float bowls and the jets. Then I will probably just spray some carb cleaner everywhere I can to make everything look as clean as I can. After I do all that I will fire it up and let it run, shut it off and see if there is anymore fuel leaking into the carbs.

smellycat

The carb and all the cables are really confusing. take lots of pictures. You might be able to pull the gas lines off at the carb, plast a can in there. When I had My carb apart. the only part that was gunked was the float chamber and the little valves they open and close

bahlorm

Yeah I took my carb apart and there was like 1/4 of an inch of gunk just sitting at the bottom of the float bowls and everything was gunked up. I just soaked it in carb cleaner and put all the jets in a cup with carb cleaner to soak in. I will be putting it together today since it has had close to 24 hrs to soak up and I will see if it helps anything out. I also realized the fuel filter in the back of the car was so old, it came out in 3 pieces and it was hardly even letting gas pour out of it. So after being told that was changed. It obviously was not.

bahlorm

Okay, before I had a flooding problem. I took the carburetor apart replaced the floats, cleaned the float bowl (that was full of gunk), cleaned the jets out (that was also full of gunk), and put in a new fuel filter (even more full of gunk). I also took off all the vacuum hoses leading to the rats nest, and capped off all the places where the hoses go (and I made sure I did them all). The car used to have a hesitation when you hit the gas and now that is gone, the car now idles at 900-1000 rpm and I can live with that. This car just drives amazing now when I just took it out. BUT when I took it out the car would not rev past 4500 rpm. It had quite a bit more power until I got to that point then it was acting like it was red lined. I know my gauge is correct and before I took the carburetor apart it would rev past 7000. I am wondering if maybe there is something I forgot to do, or maybe if there is something I did not do correctly when putting the top of the carburetor back into place. The car idles and drives perfect until you hit 4500 rpm then it will just stop. So does anyone know exactly what could be the cause of this? Like could there be a vacuum hose I may of missed? If so which one would be the cause of this? Or is there something inside the carburetor I may of done wrong?

74RX4

iTrader: (10)

Sounds like your secondary throttle plates are not opening. Make sure you have the linkage from the diaphragm hooked up.

You can put the gasket between the upper and lower carb bodies on backwards and vacuum will not reach the secondary diaphragm.

http://intertron.com/ron/images/sv2.jpg
http://intertron.com/ron/images/sv3.jpg
http://intertron.com/ron/images/sv4.jpg

bahlorm

Since I really only needed the upper gasket, I just bought some gasket sealant. Is that vacuum passage in the upper or lower part of the carburetor? I might of gotten it covered by the gasket sealant on accident or maybe it is leaking. Maybe it is best just to get the rebuild kit for it then if that is the case.