Oil pump hoses

Max Fan · Post by **Max Fan** » Tue Jan 06, 2009 8:39 pm

Hi guys....Great site. I have my '84 V-Max back together and running. There are two oil lines coming from the oil tank and then connect to the oil pump. The large "Barb" from the tank goes to the oil filter, then to the pump. What's with the other line on the tank ? Is this a "Return" line or something ? It can't be a feed to the pump or there would be another filter on it. The other thing is does it matter which is which when you connect to the pump ? I've looked in my service manual but I can't tell from the picture. The pump has two barbs for the oil lines....one is a " In" and maybe the other one is an "out" ....thanks for your help.....Tony.

opsled · Post by **opsled** » Tue Jan 06, 2009 9:20 pm

Hi Tony, Yes the second line is a return. The "in" line with the filter goes on the oil pump port with the bleeder screw next to it. That is the easiest way to tell which is which on any Yamaha pump. The bleed screw is there to purge the incoming oil line of air and prime the pump before you start the engine so that is the one you want filtered.

Good Luck, Phil (opsled)

Max Fan · Post by **Max Fan** » Wed Jan 07, 2009 1:02 am

Thanks Phil !

I was able to bleed the air out of the lines. I ran the oil pump at WOT like the manual said,
it worked perfectly ! I could see the oil mixing with the fuel right near the plastic "Tees" before it entered the fuel pumps. All of the air bubbles are gone, sled runs just great !
Thanks again for your help Phil........Tony.