Question concerning amount of oil and pump ?

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pearljam724
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Suzuki 2-Strokes: 75- GT 550 / 76- GT 750
Location: SW PA

Question concerning amount of oil and pump ?

Post by pearljam724 »

I've read in the manual about setting the marks on the oil pump arm and pump in relation to throttle input. But no where does it state on which side of the mark increases or decreases amount of oil pumped. I assume if the mark on the arm is above the mark on the pump you are pumping more oil ? On my 550 the arm mark is about a quarter inch below the mark on the pump with no throttle input. I adjusted my 750 at the same setting knowing my 550 is getting plenty of oil. I'm pretty sure my 750 has air in the pump until I get a chance tomorrow to bleed it off. Question is, how can I increase the amount of oil ? Adjust the pump arm mark up toward the top of the pump ? Same direction the arm swings when throttle is increased, correct ? In my Clymer manual it shows an early model 750 with adjustment marks on the carbs too. Mine is a 76, does it have those adjustment marks on the carbs too ? My understanding from the manual is both marks on the arm and pump should align when the bike is idling ? Is that correct ? When I adjust it there the bike will not smoke the slightest. Even under heavy throttle. As if it is getting no oil in that position. When I adjust it a quarter below the oil pump mark it smokes very little. Sorry, I'm in the early stages of learning these bikes. Thank you.
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pearljam724
AMA Superbike
Posts: 1681
Joined: Tue Jul 24, 2012 11:45 pm
Country: U.S.
Suzuki 2-Strokes: 75- GT 550 / 76- GT 750
Location: SW PA

Re: Question concerning amount of oil and pump ?

Post by pearljam724 »

Bump.
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jabcb
Moto GP
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: Question concerning amount of oil and pump ?

Post by jabcb »

Oil pump adjustment and output specs are listed in service bulletin Specification-10.
http://www.ozebook.com/compendium/techb ... 010-14.pdf

The T250/T350 service manual shows the oil pump output curve when you open up the throttle & keep rpm constant.
Output curve for the other bikes are likely to be similar. The T250 output curve is:
T250_OilPumpOutput.jpeg
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T500 69 project & 73 project
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