Anyone remember what the trick was with getting a 454 carb to do worth a crap. My cousin's is acting up again. Blowing black smoke and dying all the time at idle. What was it they did to help this? I know he needs to clean the air filter, and needs a plug, but still, something isn't dialed in right. I took the damn carb apart and cleaned it out tonight, but thats about all I can do. I don't know anything about adjusting them.

 

4 years later, its still a piece of crap! Too bad I didn't get any replies to this one back then. But, while I'm on it, anyone know what the float height should be for a 1998 454 with a 34mm Mikuni carb?

 

Try 14mm or in US speak .6".

 

I found that in an old post, but its extremely high. Like so high that it would have the float fully extended downward with the valve shut full time. I suddenly noticed that the threads are worn on the choke cable, and thus, its like the choke was on full time, because it wasn't even barely attached to the carb. So I have it cleaned up and back together and if the cable comes out again, we'll just get a new one ordered. I've got a feeling that was what was wrong with that thing this time around. They don't call it "The Poorwheeler" for nothing.

 

Andy, when you have the carb apart be sure to check the jet tube and the needle very carfully for wear. The tube will show the most wear but I always replace them together. If unit is loading up on idle and dying then this is the most likely cause. Tube gets worn and hole gets either to big or oblong and needle can't shut fuel off at idle so you are pulling fuel through idle and main and over fueling. The 454's were a bit fussier to work on but they are a battleaxe. Have seen them take alot of abuse and there are still alot of them out there. Hope this helps,TORK