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1990 FJ1200


Johan Roelofse
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Hi guys. I got a fj1200 last month, stood for 2years. Well, got the bike, fitted rings, spark plugs and cleaned the carbs. When trying to sync the carbs, it doesnt idle. Mixture screws is 2 turns out, float correct, jets(pilot and main) newly fitted. Bike runs well if I close the intake of the 4th cylinder carb. Gas going to all the carbs, Struggles to start as well. while i am keeping the bike running with the accelerator and sprying some engine start on carb no 4, it runs well for a few seconds. Took the carb apart, and now if I crank the engine, gas spits out of the air jet. WTF! any anwsers?

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Have you checked the diaphragms ? If they are leaking then getting it to idle will be a problem, if you find that the diaphragms are holed then you can paint then with a rubber solution to seal over the leaks, I have used in the past PLASTIDIP paint, it's flexible enough to move with the rubber and is not affected by petrol. To check take the things out and hold them up to the light, if you can see through anywhere then that's your problem. If you want to buy new then you had better be sitting down as they cost a bloody fortune, the cheapest I have found in the UK are from the FJ owners club and I think that was something in the region of £144 for the 4 follow this link http://www.fjcatalogue.com/catalog/item/7220095/7430630.htm to see them for yourself. Hope that helps if that is your problem.

Other than that I have heard that if the bike sits with fuel in the carbs for a while then it tends to block the air ways inside the carb NOT the fuel channels but the air flow, the only way to clear them is to get them into a sonic bath and leave them for hours as they are really difficult to clean, from those that know it has been known to have to actually ditch the carbs altogether as they can be impossible to clean. Sorry about that but them's the facts that I know, if you read the back issues of the FJ owners club magazine you can read all about it yourself.

Just had another thought on this and as it's the number 4 carb then it might just be that one that's blocked inside, especially if it was on the side stand for a long time, number 4 carb would be the lowest due to the lean of the bike, just a thought really might help you or might not.

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