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Discussion Starter · #1 ·
I have a 1978 Exciter. I went up to the salvage yard and got cylinders,heads,carbs off a phaer 485. Every thing went well with the build, The cyclinders looked good. I honed them out and installed new pistons. It had boyseen Reed also. Now my problem is it starts and idles great, But when I stab the throttle it pucks. I dont have an air box on it yet and plan on putting foam air cleaners on it. I have cleaned the carbs very well several times. I have put new choke plungers in. The rubber plugs are in ruff shape but seem fine. I have them installed in the middle port and the other in the one with the jet in it. Is this correct? I do have new rubber plugs on order. If I throw the choke on it hits and ribs but then it will puck. I'm thinking its some Kind of fuel problem.:dunno: I am stumped here. Any help would be great. We have a backyard race coming up with pre 1982 and 440cc sleds. I guess this is what I get for trying to pull a fast one.
 

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Discussion Starter · #2 ·
Just an update. My main jets are 147.5 and my tube jet is a 3a. My floats were way out of adjustment. I checked my oil injection and that was good. My buddy is picking me up some smaller jets, 143.5. I'm at sea level. I don't think the mains were big enough to give me the problem, but not sure about the affects of the floats being out of adjustment. Wish me luck.;) Also I'm using the stock exciter fuel pump with a single outlet and I just put a T in. The Phazer use's a twin outlet pump. Does anyone think that should be a problem?
 

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Breaker of Balls
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good luck
 

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Discussion Starter · #4 ·
Ok, no luck. Just put 145 mains, adjusted the floats and oil injection, and new plugs. I also put some foam UNI filters on it since I can't use the stock air box. Starts and idles fine. I let it warm up on the stand and stab the throttle and it pukes. If I try to get into it real easy it will rev up great and sound awsome then I'll try to stab it and it pukes. Please, I need some advice.
 

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probably has to do with the lack of an airbox. even sock filters will restrict airflow. its kinda a no-no to run the sled with unrestricted air. makes them do funny things. theres alot of engineering that goes into an airbox.

a more compatable fuel pump probably wouldnt hurt either.

as for the rubber plugs, center and right are covered, as your looking to the carbs from the seat.
 

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Discussion Starter · #6 ·
Just borrowed another set of carbs off a phazer and the exciter ran awsome. Lots of power. I compared everything between the two carbs and they are identical. So I guess I must have a blockage some where. I'll keep at it but so far what a differance between the 433 cylinders and the 485 s.:D
 

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there is more to cleaning a carb than simply removing a jet or two and blowing it out.

what does a jet do? it meters fuel. if a jet is installed into a passage, and you simply clean the jet and not the passage, you havent cleaned the carb.

its an in and out thing. what goes into the carb needs to come out, be it air or fuel.

every orifice, passage, circuit on a carb should be addressed. and every one should go in one end and come out another. if your blowing air or squirting cleaner into a hole in the carb, it should show up and come out somewhere else on the carb.

this is why it is crucial to remove not only the jets, but the air/fuel screw, the float and needle, seat if possible. choke plunger, etc. if these items havent been removed and blown/sprayed through, you havent thoroughly cleaned a carb.

this is not at all directed at you, but more so written so others may see, read and learn.
 

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I would definitely take a look at your carbs again and make sure EVERYTHING is thoroughly cleaned. I had a stuck needle on my float and that caused gas to stop flowing into the carb. It is best to check everything and just like Yamadad said "when fluid or air goes in one whole it must come out somewhere else." make sure all orifices are clean.
 
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