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Zenith single carb problems

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If Hawaii Import parts cannot procure an egr valve for you, then I suggest blocking it off. Plug or plate over the opening. As long as there is no leak, no problem...
 
The bracket they sent me is a kinda v shaped price of metal with three large holes and two small holes, one on each side of the center larger hole in it. I think this may not be a correct part for this car.
 
Ofcalipka said:
The bracket they sent me is a kinda v shaped price of metal with three large holes and two small holes, one on each side of the center larger hole in it. I think this may not be a correct part for this car.
Click to expand...

can you post a pic?
 
Moss finally got back to me and sure enough Its the wrong part for my carb. Does anyone have a photo of how the stock manual choke is supposed to be set up correctly on the 1500 with a single zienith?
 
Well I got it all back together, still waiting for the adsorption cannister but the lines are run to plug it in when it does also for now I capped off the EGR holes for now until the new part comes in. She is running okay. The idle keeps racing from time to time but that may just be some crud still in the fuel. So since she idled so well in the garage I took her for a test drive. I got about a mile before she starts sputtering out and backfiring and then cleans up runs okay for another half mile then really started get bad and dying out all the way home. I checked under the bonnet and find the fuel filter seems dry. So I hook up the electric pump again and start her up fuel filter fills up and she smooths out a little. So I take for another test drive and get as far as the end of my driveway where it dies. I start it back up and get her back into the garage and again the fuel filter is nearly dry. I think the fuel line or the pick up is bad. So I guess tomorrow I will drain the 7-8 gallons of fuel out of the tank and try to drop the tank to inspect the fuel line and possibly make a new steel line from whatever stock the local auto parts store has in. Anyone had experiance with this that could let me know what to expect other than smelling like petrol for the rest of the day?
 
I believe that there is a mesh screen at the end of the fuel pickup in the tank that gets clogged. Certainly sounds like it is upstream of the fuel filter leaving the most likely something in the tank. My guess is that you need to drop the tank. At that point, I'd blow out the lines in place. I know there are those who would put nuts or bearings in the tank to loosen crud. I'd be inclined to find a gas tank shop and let them boil it and possibly reline it.
 
Doh! just realized you have a Midget (not sure why I didn't notice before - I think I assumed because you were here... ) anyway, you might want to even moce the link to the Spridgets board if you aren't getting anywhere
 
Does the 1976 1500 qualify as a spridget? I kinda thought that term reffered to the older midgets only especially since mine has the rubber bumpers and all. Remember now while I may have rebuilt a few cars in my time, I'm a newbie to midgets so I don't quite have a grasp on all the terminology for these wonderful little cars yet.
 
Ooops - should clarify Sprite + Midget = Spridget, all years all models. BTW Mine's a '76 too but we ave up to '79
 
Ofcalipka said:
Does the 1976 1500 qualify as a spridget? I kinda thought that term reffered to the older midgets only especially since mine has the rubber bumpers and all. Remember now while I may have rebuilt a few cars in my time, I'm a newbie to midgets so I don't quite have a grasp on all the terminology for these wonderful little cars yet.
Click to expand...

The beast qualifies. :thumbsup: :wink:
 
Right on Spridget it is then. I pulled the tank off the car and, well, I knew the fuel was somewhat contaminated but I never though it could have been as bad as it was. There must have been over a 1/4 inch of crud lining most of the tank so I soaked it in simple green and water for a while then rinsed it out and a slurry of goo the likes of which I have only noticed in gas station bathrooms comes running out and still there is a whole bunch of nastiness in the tank. So I pulled out the old pressure washer and hit as much of the inside of the tank as I could. About 1/2 an hour later I finally started seeing clean metal on the inside of the tank. Finally got it clean enough to my satisfaction and treated the metal with a tank treatment and now I'm waiting for it to dry up and I'll put it back on. Hopefully this will help get her back to running right. There is a cruise night I would really like to go to tomorrow night.
 
glad that's all it was - how's your fuel filter look? Has it stopped any crud or was it just preventing flow out of the tank.
 
The filter was catching a small amount of crud before but now that I cleaned and reinstalled the tank it is full of fuel and instead of being kind of brownish it is now nice and clear like it is supposed to be. I was just getting her down off the jack stands when the rain started to come down in buckets. I'm hoping it will let up in a while and I can try another test drive. Also I checked the fuel gauge sender while I had it out and found it was stuck. I just moved it up and down a couple of times and it loosened up and seems to be sending the proper signal to the fuel gauge now. The motor still doesn't idle very smoothly still yet even after it gets up to operating temperature. I think it is still running rather rich as I see a little bit of smoke coming out of the exhaust and the plugs look all sooty still yet every time I check them. I keep turning the adjusting screw in the dashpot counterclockwise about 1/4 turn at a time but it doesn't seem to affect the engine operation at all. Also I think I found a picture of how the choke cable is supposed to mount on the internet. It looks like it is a really small little metal clip that just snaps onto the side of the bracket that holds the throttle cable. Anyone know where I can find one of these? I'm going to try the hardware store and see if I can't figure out a workable alternative.
 
Okay rain finally stopped and I took it for a test drive, it was fine for a couple miles around town so I figured I'd try the freeway. As soon as I tried to accelerate up to speed she started bogging down and died out. So I hook up the electric fuel pump as I know this one is good and try again. But it still won't go on the freeway. I get back off the freeway and she gives me some trouble for a little bit then cleans up and is fine again. She seems fine until I try to put a full load on her. The only possible thing I can think of is the adjustment I made to the float since nothing else is showing any fault that I can find. After she cools down I'm going to try and put it back to the factory setting. Anyone have any other ideas what might be causing this? She is so close to running right but the problem still seems to be eluding me.
 
excuse me, but do I recall that you have two fuel pumps, one back by the tank and the other someplace else, and that you are not running them both? I had a problem similar to what you seem to be experiencing with a Jeep once...running the mechanical pump in the engine and using a new tank with an internal pump. It had symptoms a lot like you are describing. Once we dropped the tank and remover the electric fuel pump, our problems disappeared. Just a thought here...get the gas flowing at a controlled constant and retune! Good Luck

Bruce
 
Let's eliminate.

1. presumably tank is clean - check
2. fuel pump not an issue as problem appears with either pump.
3. (just to make sure it isn't a fuel line issue - have you disconnected the fuel line at carb and turned over the engine to see that good flow comes out?)


This leaves the carb and basically 2 possibilities

1. float
1a. check float level - 16-17 mm (.625-.672 in.)
1b. check the float jet - attach a small piece of hose, blow through, turn
upside down, should close and reopen when right side up (or manually close
with finger when adjusting float)

2. Carb itself - this is either rich/ lean/ choke (rich)

when it bogs down, I presume it feels like it is drowning rather than getting too little gas? In which case richness is the issue.

In this case, I'm going to go back to suggesting you restrict airflow - I know I sound like a broken record on this but, I tried it and it worked. The ZS was not designed to be adjusted like an SU. thus most adjustments you can make are too fine for a big difference. (at the bottom of this post will be links to just two of the discussions)

OR - what's up with your choke? These originally came with water chokes. I presume yours has been converted. I was talking to Joe Curto (stateside carb guy) and he said, take the choke off and manually adjust the lever to see if you can adjust richness. You might have choke permanently partially on.

those are my two best guesses - let us know how it goes.

https://tinyurl.com/dyauq9

https://tinyurl.com/bvpes7
 
The electric fuel pump is one of those aftermarket type ones that is hooked up on the firewall not the tank. Just FYI. I'm going to check that jet again as well as the float level today JP. Something else occured to me that I'm going to check. I think it's fine but I haven't disassembled the distributor to verify the weights and vacuum advance are okay. I'll update after I've done all that.
 
Checked the distributor it was fine. Readjusted the float and cleaned the carb again there was some sort of strange residue in the throat. I'm not sure what that could have been. I took it for a test drive again and this time it got up to speed on the freeway and was good except for a few minor performance problems and the idle still being a bit rough. After the EGR valve comes in I'm going to try the tape on the filter to see if that will lean it out right.
 
may have been old varnish? anyway, glad to hear you're making progress!
 
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