98 formula z stator testing

plumcrazycuda5

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Im not sure why the oil pump wasnt returning all the way back, if i push the throttle and let off i noticed there was a little slack in the cable until i pushed it back by hand, then the marks line up and cable is tight. I read somewhere else that it is common on those pumps i guess. I also realized that my throttle return springs were cut way to short after pulling some off a 95 formula, they were about 3 times longer then mine so i will use those. I think its just a bunch of little things causing my problems. The one spring was cut so short that it coudnt push the slide all the way down so was basicly just the weight of the slide pulling it back to idle position. Someone sure messed these carbs up i think. I put a light guage spring on the oil pump arm so it returns all the way now but i read that these oil pumps do not flow any oil at idle position? Seems odd to me and makes a guy a bit nervous. I will update once i get my new needles and needle jets in. Thanks again
 
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Modman

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Im not sure why the oil pump wasnt returning all the way back, if i push the throttle and let off i noticed there was a little slack in the cable until i pushed it back by hand, then the marks line up and cable is tight. I read somewhere else that it is common on those pumps i guess. I also realized that my throttle return springs were cut way to short after pulling some off a 95 formula, they were about 3 times longer then mine so i will use those. I think its just a bunch of little things causing my problems. The one spring was cut so short that it coudnt push the slide all the way down so was basicly just the weight of the slide pulling it back to idle position. Someone sure messed these carbs up i think. I put a light guage spring on the oil pump arm so it returns all the way now but i read that these oil pumps do not flow any oil at idle position? Seems odd to me and makes a guy a bit nervous. I will update once i get my new needles and needle jets in. Thanks again

You're too rich. Put the 20 pilots back in, back the air screws out 2 turns. stock is anywhere from 1.5 to 1.75 turns out from fully seated. The idle should be set at 1700 RPM. There is a number on the bottom of the carb slide, it should be 2.5. You might have a leaking needle and seat in the float bowl, check your float heights anbd maybe replace the needles and seats. They have been known to leak. Leave the oil pump alone until you solve the fuel issue. You can also run a BR8ES plug instead of the 9, that will increase the ignition temp on the plug by about 450 F, which will help your plug fouling.
 

DRD

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What Modman said, I'd also try a BR9EYA plug, same heat range but anti-foul design.
 
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plumcrazycuda5

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Thanks for the replies, the needles and seats are new, i tried 2 different sets of them and my floats are also set right. Even with the 20 pilots it would barely idle with the idle screws all the way in. I backed out the mixture screws to 3.5 turns and it would idle around 1000rpm. I will check my slides and make sure they are the right ones. I think my needles are bent, i have new jet needles, needle jets and exhaust valve bellows coming. They should be here in the next couple days. Thanks for the info.
 

plumcrazycuda5

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I installed new jet needles, needle jets, exhaust valve bellows and checked my rotary valve and it was off one notch so put it where it is supposed to be and pretty much no change. Everything in the carbs is new and they are set to factory settings and it still doesnt want to idle barely. I havnt had a chance to drive it yet but ran it with the back end up and made sure if it was flooded that the fuel was cleared out. A couple questions....should the pulse line from crank case to fuel pump be completely dry? There is not fuel sitting in the hose but it does look damp inside. It was a brand new pump when motor was rebuilt 1300kms ago. Second question....after i dropped the rebuilt motor in should i have had to set the timing or anything like that? The engine builder didnt say anything about it but am just curious as I think you would have to. Thanks again
 
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