'81 510 Wagon Resurrection

[spoiledmilkwagon]

Hey y'all,

 

Just rescued a 1981 510 Wagon, all original North Carolina car. Z20s engine, 4 speed manual, a little rusty but that doesn't bother me much. The car drives fantastic, no issues there. My issue with the car right now is that it does not idle below 1050 rpm and "diesels" badly when switched off. If I can get the idle down, it idles rough and eventually sputters and dies. Seems to be running rich. I've gone through all the vacuum lines to assure no leaks, adjusted timing, and exhausted all (2) tuning options for the Hitachi carb, ensured that the choke and idle shutoff solenoid are both working properly. Also went through the ignition system from coils to plugs, all is well there. It seems my issue is no fuel in the idle circuit as I have fuel dripping from my primary at idle (tried removing idle cut solenoid pin with no change). Took the carb off the engine, disassembled and cleaned thoroughly. Replaced with new gasket and no change. Have a new carb on order but wanted to know if I'm missing something obvious (or not so obvious).

 

Thanks!

Edited August 29, 2023 by spoiledmilkwagon
All text was highlighted accidentally.

[datzenmike]

Is it still dripping? If yes this would indicate that it's flooding or float chamber is over full. There should be a small round sight glass on the front of the carburetor with a dot on it. Fuel level should be close to the dot. 

 

 

The idle cut when ON allows fuel down to the idle mixture screw. Turn screw out to add fuel to the idle and in to lean it out. You didn't mention any adjustment so that might be it.

[spoiledmilkwagon]

Mike, yes, after the cleaning, its still dripping. The fuel bowl level is right on the dot. While the carb was off, I measured the float level and float drop with a feeler gauge and they were both right on the money. As for the idle adjustment screw, I turned it all the way in and backed it out 3-1/2 as per the carb document I have. Seems to make no difference whether its 3 turns out or 10 turns out. I can cover the primary with my finger and the car will immediately die indicating there is no fuel in the idle circuit. The only way I'm able to keep it running now is to have the throttle adjustment screw turned in a few turns.  

[spoiledmilkwagon]

I'll add for anyone reading this... replaced my carb with a $90 Chinese Ebay hitachi knockoff and it runs perfectly. Wasn't expecting much but took the chance and I'm thoroughly pleased.

[datzenmike]

I would replace the fuel filter if not done previously to keep that carburetor clean. Well that's good news about the Chinese carburetor. Let's hope it continues.

 

Don't throw away old parts. There is always something on them that can be used.