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1990 xp 100 Evinrude

R

Rhigley

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I changed out both filters{water separator and inline) fresh gas and it still starves at WOT after a few seconds. On e more note is that at idle my tac says 1000 rpms and in gear it drops to 700 rpm but wide open goes to over 6000. I pulled the throttle back to 5000rpm and it ran longer but still starved for gas at the end. My fuel bulb was not sucked in but is still was not firm. Help please...Is it my fuel pump? I just put a new gas tank in it about one year ago. Thanks
 
One simple thing to try is to have an assistant operate the manual pump and see if the motor keeps running at WOT.-----What boat and what pitch on the prop ?
 
Its on an old Galaxy bow rider (1988 I think) 17 foot. I did put a different prop on it off the old Johnson 88 that was on the boat when I got it. Only reason I put this prop on was because it was chrome. I'll replace it with the one that was on this engine and see if that helps. I just ran it for over 30 min. at 4000 rpm and no problems at all at that speed. Thanks again for all your help. Not sure how good the tac is. It's the one that came in the boat. It was set for a V8 when I got it so not sure if I can go too much by that.
 
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OK did the primer bulb trick today and it helped. I think I might need a pump or rebuild this one. I do a fuel mix because I did a VRO bypass. Do I need a different fuel pump or can I rebuild this one?
 
There is an inexpensive fuel pump available.------It bolts directly to the intake manifold near the starter motor.----Cheaper that a rebuild kit for a VRO pump.
 
When I had the motor placed on the boat they said the VRO pump was not working and said they would by-pass it and I would need to do a 50/1 mix. Dose anyone have a part number for a replacement fuel pump? I don't mind doing the mix thing. It takes one less warring away from something else failing on the water.
 
Look for the pump part # right on this site.----Look it up for an 88 hp model and any year of the 88 hp model will work on your motor !
 
I pulled off the prop I was using (Stiletto 21317 01317) and placed the one that came on the motor back on (13 1/4 x 17) Will this make a difference on my boat?
 
I pulled the old VRO/fuel pump out and ready to get the fuel pump only for the 88. I know the inlet is from the fuel filter and I think the outlet goes to the split manifold to the carbs. I have one more line that comes motor side (thinking it's some sort of pules/vac) can anyone help me with this. I think I see the spot that this 88 pump bolts up to the block and it has a flat head plug in it that I think I need to remove and place the mounting gasket over that when I mount the pump. This pules/vac line is just under that place on the motor.
 
?----Remove the pulse limiter and plug the pulse port that drove the VRO.-----Remove the plug between the 2 threaded 10-24 screw holes and install the pump with the gasket.----The replacement simple pump needs fuel in and a fuel out hose.----The + pressure and slight - tive pulses come from the hole that now has the plug in it.
 
cool.. thanks do you know what size plug I need for the pulse hole? I tried to remove it but couldn't find the size of the nut. Is it metric?
 
Got the pulse connection out and now I'm trying to find the plug to replace it. My local boat shop is closed for the holidays so I'm kind of stuck .Don't want to mess up the threads on the block. Not sure if I need brass plug or what. Anyone have any ideas for me on this..Thanks
 
??---Take the pulse limiter to the hardware store.----Get the kids there to help you find a pipe plug like that.----1/8-NPT is what you might need.
 
Got the fuel pump installed and the plug for the pulse. Thanks everyone for all your help. I'm going to check the timing on the water, seems to be the easiest way to go.
 
I have a manual from Seloc and looking to see what thumb screw I should be moving to set timing. I have one about in the middle of the throttle leakage and one top under the fly wheel. It looks to me that the one under the fly wheel would be the one but I don't want to mess this up. Anyone can give me the one I need to adjust I would appreciate it. You guys got me this far and I'm almost their :) Thanks again.
 
Timing is set for the life of the motor.----Be very carefull and read a factory manual before making any timing changes !!
 
I'm checking to see if is what the book says it should be (4 ATC and 28 BTC) and if is was not, I would like to try and get it set.
 
You only set the maximum advance timing which is 28 BTDC.-----The 4 ATC is NOT something you set.----It is the point where throttle plates open.----Be sure of what you are adjusting !!
 
That's what I am trying to do. I'm hoping all is well the way it is ,but if it way off I want to try to bring it back to the 28..I see 2 thumb screws with locking nuts on them. One is about mid throttle and the other is under fly wheel. The book I have dose not explain it very good to me.
 
I think I see what's going on with the thumb rollers, the bottom one looks like it centers the cam to the center notch and the one under the fly wheel is the timing. Dose this sound right?
 
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