Oil Pump Problems

mnellis · Post by **mnellis** » Sun May 23, 2010 3:39 pm

I'm having problems with the injection pump again. The right side oil lines (2) are filling with air where the single line leaves the pump. The banjo connections are all tight with new crush washers so I've been thinking it might be a pump problem.

Is this a common problem and is the pump serviceable if I take it apart.

Thanks

Mike

Post by **oldjapanesebikes** » Mon May 24, 2010 10:56 am

Is this on a T/GT500 ? Someone else will chime in I'm sure, but if its on a 500 then it could be a check valve problem.

mnellis · Post by **mnellis** » Mon May 24, 2010 5:11 pm

Yes, this is a T500 but the problem seems to be where the oil leaves the pump. I'm trying to figure out in my pea brain if a sticking check valve would cause the oil bubbles I'm seeing where it leaves the pump.

diamondj · Post by **diamondj** » Mon May 24, 2010 6:32 pm

Are the crush washers metal or plastic? If they are metal, try putting a light smear of Honda bond/Yamabond/etc. case sealer on each side of the aluminum washer. Also look at the joints where the metal fitting goes into the oil hose - a smear of sealer there might help as well. Also check your supply line from the oil tank into the pump as you might have an air leak there. Also try sealing the y where the right side line splits into two. And check the two bolts that fasten the oil pump to the crankcase - are they torqued down correctly and is the gasket under them in good shape?

Beyond that, it could just be you have a pinhole in the right side line and the bubbles are coming from there. You could try wrapping the line with electrical tape an inch or so at a time to find the pinhole (if all else fails).

Jim

mnellis · Post by **mnellis** » Mon May 24, 2010 10:00 pm

diamondj wrote:Are the crush washers metal or plastic? If they are metal, try putting a light smear of Honda bond/Yamabond/etc. case sealer on each side of the aluminum washer. Also look at the joints where the metal fitting goes into the oil hose - a smear of sealer there might help as well. Also check your supply line from the oil tank into the pump as you might have an air leak there. Also try sealing the y where the right side line splits into two. And check the two bolts that fasten the oil pump to the crankcase - are they torqued down correctly and is the gasket under them in good shape?

Beyond that, it could just be you have a pinhole in the right side line and the bubbles are coming from there. You could try wrapping the line with electrical tape an inch or so at a time to find the pinhole (if all else fails).

Jim

Thanks Jim, those are all good ideas. I replaced all the crush washers a few months ago and they were aluminum.

Odin · Post by **Odin** » Wed May 26, 2010 11:09 pm

if you use yamabond or honda bond just be careful, I did that to find a leak in my lines and a tiny piece was drawn in and plugged the check valve.
I can't remember if the T500 pump has the bleeder bolt (reverse thread) if so you my want to check that as well.