Walbro WT-990 disappointed.

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50:1 is pretty lean if you don't have good experience with tuning. Just saying By the looks of this thread I would stick with 25:1until you learn the nature of these beasts
 
Yeah, that's what I plan on doing need to develop the ear to so tuning becomes a breeze before actually messing with other mixtures.
 
Ok been trying to tune the carb and I think I got the HSN set but when hitting the brake it will die and I can't remember but I think that means the LSN is too lean right?
 
If it dies with brake, check the idle screw, and throttle trim.

If you watch the carb linkage it should not close any more it idle, than when you brake.
 
andyken said:
If it dies with brake, check the idle screw, and throttle trim.If you watch the carb linkage it should not close any more it idle, than when you brake.
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does the idle screw need to be turned to the left or right, it's kinda hard to tell right now with the linkage because when I apply the break then left off it engages the throttle and I have to hit the throttle to get it to go back to idle so it's not going to idle position after letting off the break, I hope this makes sense lol.
 
Check the part that slides up and down on ur linkage its probably sticking u might have to loosen the screw and shoot it with some lube.mine was sticking at one time and was causing the same problem it would lunge foward when i hit the brake.look real close as u hit the brake.hope that helps...
 
Ildy666 said:
Check the part that slides up and down on ur linkage its probably sticking u might have to loosen the screw and shoot it with some lube.mine was sticking at one time and was causing the same problem it would lunge foward when i hit the brake.look real close as u hit the brake.hope that helps...
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What part are you talking about, I don't see a piece that goes up and down
 
It contacts the brake spring.mine had grit in it making it stick applying throttle after applying the brake then releasing.clean and lube it.if u run the car watch close it only does it slightly but enuff for it to apply throttle.a least that was my problem...good luck...
 
Ildy666 said:
It contacts the brake spring.mine had grit in it making it stick applying throttle after applying the brake then releasing.clean and lube it.if u run the car watch close it only does it slightly but enuff for it to apply throttle.a least that was my problem...good luck...
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I have no piece on my MT that connects to the brake spring that moves up and down. My linkage only moves side to side (left and right).
 
I also have a mt.its a little black piece of plastic has screw to secure it it rides on the linkage it applies the brake against the coller that contacts the spring.
 
Ildy666 said:
I also have a mt.its a little black piece of plastic has screw to secure it it rides on the linkage it applies the brake against the coller that contacts the spring.
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Do you mind taking a pic of what you're talking about, I'm looking at my MT right now and really don't see the piece you're talking about sorry for being a noob lol.
 
andyken said:
There should be a collar/set screw and spring on the metal linkage
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Yes there is a metal collar with a set screw in it with a spring that's in between that and the little small rod that the linkage it's self goes in and that part is really clean and tight.
 
i hate to confuse you but i was having a terrible time trying to tune my rampage also and finally found the issue. my intake block was not tight against my motor and was sucking in air,making it impossible to tune. i would push side to side on your carb,if it wobbles from the intake manifold, it is loose.take off the carb by the two carb screws, then tighten the intake screws. sorry if this info doesn't help, but it sure helped me once i fgured out what it was. seams as though they werent tight when my rampage was assembled from the factory
 
kbreaux100 said:
i hate to confuse you but i was having a terrible time trying to tune my rampage also and finally found the issue. my intake block was not tight against my motor and was sucking in air,making it impossible to tune. i would push side to side on your carb,if it wobbles from the intake manifold, it is loose.take off the carb by the two carb screws, then tighten the intake screws. sorry if this info doesn't help, but it sure helped me once i fgured out what it was. seams as though they werent tight when my rampage was assembled from the factory
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Thanks for the advice but the manifold and carb is on very tight, I got everything set now, I was even able to go out this morning with the filter on and start it took about 10 pulls but it fired up with no special tricks so I'm really happy, just have to fix the issue with letting off the brake it engaging the throttle.
 
try your low speed needle counter clockwise .. let the car warm up then try it and wait 5 seconds after each movement to see if the motor catches up with the change in needle movement.
 
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