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Motorcycle Repair/1990 fatboy oil hose routing


oil lines
oil lines  
QUESTION: i replaced my oil tank. i neglected to mark hoses. in my diagram i have numbered the nipples. i had 1 going to 7, and 3 going to 8. when i started bike oil poured out of 9. i switched 1 to 8 and 3 to 7, upon starting it did same thing. HELP

ANSWER: Is that all you did was replace the oil tank? Did you open the cam cover?

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QUESTION: hi mike,
no. all i did was remove my existing tank and replace it with another. is it some kind of sump in the engine that that oil went into if i originally had the hoses crossed. and if i have them correct now as indicated, would the oil keep coming out until it empties. i am at a loss and confused. thanks for the quick response.


Your numbers on your diagram are a little hard to see, so I will just describe where the lines go. The lowest time on the tank is the feed line which goes to the feed side of the oil pump. If you are looking at the oil pump the feed line would be on top of the pump towards the outside of the bike. Once the oil goes through the motor it comes out the return side of the oil pump, located right next to the pump side. Oil then goes to the oil filter and then back to the oil tank. By your picture it would be the nipple to the left on the tank where the two nipples are close to each other. The other nipple is the vent from the engine case. You might have had the oil lines installed correctly, but if you had a lot of oil in the bottom end of the motor when you start it you will get oil out of the line that is not connected. The oil pump cannot pump the oil out fast enough so that is what happens
Good luck and happy riding

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Mike Wells


PLEASE READ BEFORE ASKING A QUESTION!!! I CAN ONLY ANSWER QUESTIONS ABOUT HARLEYS !!! I DONT KNOW ANYTHING ABOUT OTHER MODELS!!! IF YOU ASK A QUESTION ABOUT A NON HARLEY BIKE IT WILL GET REJECTED!!!I have a Harley only shop with 30 years experience located in Ohio. We specialize in complete and total repair, restoration, hi-performance, and custom bike building. I can work on Flat Heads to Twin Cams. Please, dont ask how much somthing is going to cost to fix. Labor prices differ all over te country as well as shop to shop!


If its broke on a harley we can repair it. We do complete restoration from the frame up, engine and trans rebuilding, remapping and custom bike building

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