Precision Blend for 90HP Yamaha

[snapperman]

Does anybody know how I can bleed the precision blend oiler on my 90Hp yamaha. It has been stored for sometime and I want to check the three cyclinders are getting the correct oil. The motor is approx 1990<br /><br />many thanks<br />Snapperman

 

[butlp]

Re: Precision Blend for 90HP Yamaha

snapperman,<br />I don't have the manual in front of me but from memory you do as follows:<br /><br />To bleed the pump, there is a bleed screw at the bottom of the pump that you open and let oil flow until there is no air.<br /><br />To measure that all three cylinders are getting the correct oil you really need the manual as it gives that actual volume you will see from each oil feed line at various throttle settings.<br />The general procedure is to mix 50:1 oil in your gas tank and disconnect the lines from the block and pit them into three measuring containers and at the various throttle settings you should be able to measure the volume being supplied to each cylinder.<br /><br />I think in reality, if the motor has been sitting for some time there should not be a problem unless oil has leaked. My motor had stood for a couple of years when I bought it and I removed the oil tank and cleaned it to make sure there was no sludge in the bottom and refilled with fresh oil, bled the pump as above and then ran the motor with a tank of pre-mix @ 50:1. <br />I monitored the level in the oil tank and confirmed the level was dropping so ran the next tank on straight gas.<br /><br />I have read here that the Yamaha system is very reliable and as long as you don't have any leaks will last a long time.

 

[snapperman]

Re: Precision Blend for 90HP Yamaha

Many thanks, I've located the screw. Will hopefully test it this weekend

 

[John from Madison CT]

Re: Precision Blend for 90HP Yamaha

snapperman,<br /><br /> Be sure to run a premix 50:1 for awhile until you are sure it (Precision Blend) is working properly.<br /><br /> While you bleed the screw you are depriving the engine of some oil.<br /><br /> Other than that though, these are great units with problems being rare.<br /><br />Good Luck,<br /><br />John

 

[Capt Ken]

Re: Precision Blend for 90HP Yamaha

Bleed the system while the engine is off. The easiest way to check the oiling is while the engine is running on premix, remove the oil linkage and let it go to full oiling. Remove each oil hose from the intake and watch the oil in the hose. It should pulsate out the hose. There's actually a measurment on how much should pump out in so many minutes but I've found it its pumping, its OK. Being I'm southern, I've never been able to figure out those liter, grams and meter stuff. Just give it to me in inches, pounds and quarts.

 

[snapperman]

Re: Precision Blend for 90HP Yamaha

Thanks everyone for your awesome words of wisdom<br /><br />Have a great Christmas and New Year<br /><br />Regards<br /><br />Snapperman