found the problem , now whats this part called and what does it do???

[Seas of Cheese Captain]

so back story is .....((((((
bought a ( new to me ) 1997 19 ft skeeter Mercury 150 XRI

the first three times out on the lake ran like a dream , last week on the lake again took off from the boat ramp got on plane for a while , stop to fish and troll around . then start the motor back up to leave got back on plane then the boat (on its own ) got off plane slowed down to idle . now the boat will not accelerate past idle even with the throttle all the way forward, reverse works like it should . there is a (push key in to choke ) on this boat and i'm wondering if the choke stuck ??? . causing it not to run right and where is the choke located on this motor? , is this type of choke vacuum controlled or electrical??? i've checked the spark plugs all is well there. the throttle cables work like they should . it's not a spun prop have a new prop and bushing replaced last month , checked the fuel no water in tanks)))))
http://www.bbcboards.net/showthread.php?t=1121447


after looking at it more there is a linkage missing ...said part..... this piece with the spring on it moves almost a full circle .i moved it closer to the inside of the motor then i had full power full throttle and control again with boat in water

i know it goes to there part below it with the throttle cable what's the right position for this and what is it , thanks
serial number to motor is sorry for the lack of termanology new to outboards if this was my truck i would be better ha

[Seas of Cheese Captain]

found out from another thread its the oil pump . the previous owner had trouble with the oil delivery system so he disabled it and just sticked to premixing , so my next question is. how is it me messing with what seems to be a butterfly value on the oil pump make my motor run like it should? and is there away to "delete" the pump and not have anymore running issues just stick to premixing or , do i just need to find the replacement linkage and put it back together like it should be?

[JOE54]

disconnect lnkage and get block off kit for pump