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oil pump

Posted: Sat May 08, 2010 8:36 pm
by rbond
Ok, I need info for parts fot the oil pump and how to make replacement oil lines for a GT500. Both lines to the left cylinder have a lot of air bubbles. I have not checked whether it pumps OK or not. I was syncing the carbs when I noticed this. Is there a source for the banjo bolts with the check valves? Thanks in advance.

Re: oil pump

Posted: Sat May 08, 2010 9:17 pm
by mnellis
rbond wrote:Ok, I need info for parts fot the oil pump and how to make replacement oil lines for a GT500. Both lines to the left cylinder have a lot of air bubbles. I have not checked whether it pumps OK or not. I was syncing the carbs when I noticed this. Is there a source for the banjo bolts with the check valves? Thanks in advance.
If it was working fine before you started syncing the carbs then you might have messed up the oil pump adjustment.

Try this, with the engine idling, remove the oil pump cover and activate the oil pump lever with your finger, just a little. If that caused the oil to flow in the line then check the tension of the oil pump cable. If it's loose with the throttle closed then adjust it out to add some tension. I don't know if there is an adjustment sequence for this in the manual or not.

pump

Posted: Mon May 10, 2010 11:56 am
by rbond
Let me clarify, I was using the tongue depressor method on the carbs (bike not running)when I saw the oil lines. I started it, pulled on the cable and oil shot through both lines. Long story short, it barely if at all pumps at idle. It may have some trash in it, so I would like to take it down, clean it out,etc. But I need then any 'o' rings, oil seals, gaskets for re-assembly. Just in case the plastic lines break, I need a method to make new ones.

Posted: Mon May 10, 2010 9:09 pm
by tz375
At idle with the throttle closed, the pump pushes very little oil out at all. Output volume is directly proportional to rpm so raise the revs from say 1,500 to 6,000 and output is 4 times as much.

In addition, output volume rises with throttle opening.

I don't have the 500 specs, but on the 750 with the throttle closed output is 7cc/minute to the crank at 2166 RPM and ZERO to the cylinder. At full open output rises to 7.2cc/minute at 2166rpm to the crank and 48.3cc to each cylinder.

So to recap. at 2166RPM closed throttle, oil pump output to the crank is 7cc/minute and zero to the cylinders. At WOT and say 6500 (3 times 2166), output rises to 21cc/minute to each crank bearing and 145cc/minute to each cylinder.

Not a lot going on at idle.

To check the pump, crank the cable/oil pump lever wide open for a moment and watch the oil speed past. If it responds to that, it's probably OK.