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Discussion Starter #1
So my 350 started blowing back through the carb one morning so I pulled the head and seen that the intake valve isn’t closing all the way. It isn’t bent or stuck in place. When you turn the cam over the rocker opens the valve like it’s supposed to, then when it’s closing it just barely gets stuck open and won’t close unless I use a pry bar on the valve spring, then it will snap closed but it will just do the same thing the next rotation. Please help
 

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So my 350 started blowing back through the carb one morning so I pulled the head and seen that the intake valve isn’t closing all the way. It isn’t bent or stuck in place. When you turn the cam over the rocker opens the valve like it’s supposed to, then when it’s closing it just barely gets stuck open and won’t close unless I use a pry bar on the valve spring, then it will snap closed but it will just do the same thing the next rotation. Please help
It's possible that some carbon is wedged between the valve and the guide. You'll have to pull the spring and inspect the valve.
 

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Discussion Starter #3
Ok. Do I have to remove the rockers to replace the valves? Or can I just take out the cam and push the rockers all the way up because I’m not sure how to remove the rockers.
 

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I don't own a 350 but it's more complicated then that. You'll have to pull the head and disassemble it. A valve spring compressor will also be needed. Then look at why the valve is stuck. It may also be slightly bent. Look at the piston where it may have made contact.
Need a manual? PM Morphrider with a valid email.
 

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Discussion Starter #5
I’m pretty sure it isn’t bent, there is no damage on the piston and the time didn’t jump at all so I’m either thinking it’s a bad valve spring or something is sticking in the guide like u said. I’ll try and get it out with a compresser but the rocker arm situation is bugging me. Also if I take the camshaft out is there a certain way it has to go back in?
 

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I’m pretty sure it isn’t bent, there is no damage on the piston and the time didn’t jump at all so I’m either thinking it’s a bad valve spring or something is sticking in the guide like u said. I’ll try and get it out with a compresser but the rocker arm situation is bugging me. Also if I take the camshaft out is there a certain way it has to go back in?
With the valve closed, add some solvent, alcohol, brake/carb clean, etc. to the port and see if it leaks past the valve. Lots of leakage is a bent valve, light wetness indicates needs a valve job or lapping.
I don't know 350's so check your manual for cam install.
 

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I’m pretty sure it isn’t bent, there is no damage on the piston and the time didn’t jump at all so I’m either thinking it’s a bad valve spring or something is sticking in the guide like u said. I’ll try and get it out with a compresser but the rocker arm situation is bugging me. Also if I take the camshaft out is there a certain way it has to go back in?
Screw a bolt in the rocker arm pin and use a slide hammer. From what I remember, they're threaded. I used a slide hammer to pull them out. Or you could type it into google or youtube...
 

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To pull rocker shafts on my Raptor 700's I made a slide hammer from some 8mm (I think) all thread, washers, nuts and a large heavy socket.
 

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Discussion Starter #9
Ok I got the spring out and seal but the valve is not budging it won’t come out of the guide.
 

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If it is carbon wedged in between the valve and guide, try soaking with some carb cleaner or Seafoam to dissolve it. If it's a bent valve you might need a press to push it out. Be sure to check the guide for damage. Don't hammer the valve as that may crack the guide.
 

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Maybe, it won't hurt.
 

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Does the valve look straight? Can you turn it? Try to turn it slightly, back and forth, use a pair of plyers with plastic jaws, working it out. I bet it's bent!
 

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Discussion Starter #16
It doesn’t look bent but it could be my timing did not jump either also the inside of the head is very dirty. Like black sludge
 
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