1998 Evo Softail idling on one cylinder
#13
UPDATE: I want to thank everyone that provided help and suggestions. You guys are great! I did a compression check and both cylinders are running around 120 psi. Bought new spark plugs and checked the gap at .040. Had the battery on trickle all night. Checked the spark and was getting a weak spark on both plugs and wires. Battery wouldn't even turn the engine over. I'm guessing the battery is shot. I pulled my brand new battery from my bike, installed it and the bike kicked over on the first start idling on both cylinders. So I'm guessing it was the battery. It must have some dead cells in it or something. I adjusted the Super E and got it idling pretty smooth. Which leads to my next problem.
My friend said it was making a noise coming from the front cylinder, but I couldn't ever get it idling good enough to hear it. Today I finally heard it. What it sounds like is if the front intake valve is slamming shut. I pulled the head to make sure the valve and piston weren't impacting and all is good there. I reinstalled the head, lower rocker cover and pushrods. They are non adjustable and they are in the correct order. I didn't put the carb, intake or spark plugs back on. I turned the engine over and you can clearly hear a noise coming from the intakevalve side of the front head. If you cover the intake port with your hand you can barely hear it, but pull your hand away and its plain as day. Do Evo's make this much valvetrain noise? I wouldn't think it would be normal as I can only hear it on this one valve. From what I can see when I pulled the head, it dosen't look like anything is wrong with the valves. I also noticed while turning the engine over, it doesn't make that noise everytime the valve closes. Maybe every other time at most.
I received such great suggestions from my first post, I'm hoping someone might have an idea of where I should start looking for this noise.
My friend said it was making a noise coming from the front cylinder, but I couldn't ever get it idling good enough to hear it. Today I finally heard it. What it sounds like is if the front intake valve is slamming shut. I pulled the head to make sure the valve and piston weren't impacting and all is good there. I reinstalled the head, lower rocker cover and pushrods. They are non adjustable and they are in the correct order. I didn't put the carb, intake or spark plugs back on. I turned the engine over and you can clearly hear a noise coming from the intakevalve side of the front head. If you cover the intake port with your hand you can barely hear it, but pull your hand away and its plain as day. Do Evo's make this much valvetrain noise? I wouldn't think it would be normal as I can only hear it on this one valve. From what I can see when I pulled the head, it dosen't look like anything is wrong with the valves. I also noticed while turning the engine over, it doesn't make that noise everytime the valve closes. Maybe every other time at most.
I received such great suggestions from my first post, I'm hoping someone might have an idea of where I should start looking for this noise.
#16
Join Date: Dec 2010
Location: Coromandel Peninsula New Zealand
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You can see a broken spring usually with the rocker box off, rocker pad and head of valve need rocker gear pulled to inspect and cam lobe/lifter both need lifter blocks out to see what is going on in the cam chest.
Here's a test though. Pull the top and middle rocker covers, take both plugs out and rotate the motor while carefully watching the suspect valve.....see if it makes a sudden move when the click occurs. Also check if its binds before it makes the click or lurch or whatever.
That will give you something to go on.
Here's a test though. Pull the top and middle rocker covers, take both plugs out and rotate the motor while carefully watching the suspect valve.....see if it makes a sudden move when the click occurs. Also check if its binds before it makes the click or lurch or whatever.
That will give you something to go on.
#17
I visually inspected the spring and from what I can see, its all good. Not broken or out of place at all. I did as you said to watch the valve as you turn the engine over. The valve slides well and doesn't bind or make a sudden move when the noise occurs.
I have everything buttoned up and running. Just took it for about 10 mile ride from 10 mph all the way up to around 70 mph. Everything runs good and cant hear that dang noise anymore. Im sure its prolly still there though. I think I'm gonna turn the bike back over to my buddy and see if he can find it. LOL
Thanks again to everyone for all the advice!!!
I have everything buttoned up and running. Just took it for about 10 mile ride from 10 mph all the way up to around 70 mph. Everything runs good and cant hear that dang noise anymore. Im sure its prolly still there though. I think I'm gonna turn the bike back over to my buddy and see if he can find it. LOL
Thanks again to everyone for all the advice!!!
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