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ok as most of you know ive been working on my 87 AC jag 440 f/c , yesterday i changed the fuel lines, they were the originals and were kinda brittle i was hoping that it would cure a gas smell from my sled,i noticed a wettness on the base of the carb, was hoping it was the line ,but no luck it must be the float bowl gasket so i guess i will pull the carb, now the manual says vm34 but im not sure if it is alumium or zinc, but carb kits carry two diffrent part nos so i gotta figure which it is ? is there any way to tell ?, also im sure this carb has the stock 300 main jet in it , im thinkin it might be a bit rich the book says run a 280 main below 5000 ft altitude at 0 to +20 degrees so i was figuring on a 285 main just to be on the safe side of rich, what do you guys think? any help, comments, feedback, is always appricated, thanks
 

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On a lsed of that age I think the carbs should be taken apart and cleaned. It's hard to believe that the pilots arn't partly plugged. Also the wetness you see may be fuel leaking by the needle and seat.
I don't believe that mikuni makes a 285 Main Jet. the half sizes don't start until below 200. You will have to decide on either a 280 or 290.
The Aluminum carb will stay shinny were a Zink carb gets a white corission on it. If you scrape a spot the aluminum it will be shiny and the zinc will be a dull color if scraped.


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I could only find 1 carb listed for that sled a VM34-315. I've got an 88 Eltigre with VM38s that really smelled of fuel when it was sitting in my garage. I replaced the fuel lines and took the carbs off, cleaned the needle valves and adjusted the float levels in the carbs. That was 4 years ago, fuel smell is gone. I thinks the needle valves were not closing completely, just letting small amounts of fuel seep by. Prior to that it was a bear to start, now it could be -15 and it starts on the 2nd pull. Good luck, I'd try the cleaning first, you might not have to replace anything.

RtkatZL8
 
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