Hey everyone I am new to the board and had a question about a little problem I am having on my Foreman. I notice upon start up there is tapping/knocking noise when at idle and while I go thur the gears. The weird thing is there is no loss of power and it does not smoke what so ever. When i am mid way thru the power band it seems to die down but get load at the top end of each gear. Can I get a little insight to what might be the problem. Thanks for yall help

 

Is it a pinging sound or a knocking sound. Not sure on a MC engine but from a vehicle engine perspective (should be similiar) I would venture to say that if it is knocking (pinging usually means crappy gas or insufficient timing) sound it could be a couple of things. It could be piston slap (piston wore out in cylinder bore) very unlikely. Sounds more like a crank, cam (not sure if it has one) or piston rod bearing going south. Have you checked your oil level and/or filter?

 

I have checked the oil level and it was low but add some more and the noise is still there. It is more a tapping noise rather than a pinging noise. If it was the piston and wore out hte cylinder bore wouldn't you experiance a lossof power ?

 

How long has it been, since the valve lash was adjusted?

 

well not sure to be exact i purchased it used it is set up to go be serviced on tuesday and I was trying to get an idea what i was instore for as far as what the issue could be and if it was worth fixing or reselling.

 

Wow, didn't realize they had adjustable valves. Well, I guess everything does these days. Man do I love my older truck [img]i/expressions/face-icon-small-smile.gif[/img]

If its not grossly loud and or sounds like mechanical failure I would say its your valves. Should be a minor adjustment. Let us know what you find out.

 

oh by the way i check the oil again it was low so i added some and now it smokes. what would be the man cause.

 

those push-rod engines are noisy, and a lot of those noises are normal. the valve make a ticking sound and its normal. I have a racher and my carburetor piston slaps a bit at highter rpm (like winding it out in each gear when racing somebody [img]i/expressions/face-icon-small-tongue.gif[/img] ) since it's a vacuum carburetor, there is a vacuum piston in the carb that bounces up and down, it hits the top of the carb body at higher rpm under heavy load. I think that's the noise you're hearing. If you take the air filter off and start it up, look inside the carb and rev up the engine a few times, you'll see what i'm talking about.

But there is the possibility of some engine wear, so i wouldnt rule that out. I wish i could listen to it for you, i could tell you if it's normal or not. I've had 2 brand new ranchers in the last year, but the 350 engine is amlost identical to the 450 engine except a different cylinder bore diameter. they both had a rod-knock type noise at idle, and they both did that rapping noise at high-rpm. I put 92 octane in one to see if that noise went away and it didnt, so i'm sure it wasnt pinging. like i said, it's probably just the carb making noise.

the smoking might be too full on oil, or worn piston rings. since you said you added oil (twice now) you either overfilled it, or it's using oil (smoke).

good luck

 

well thanks for the good information..I will be taking it in for service today. I hope that the noise is just something simple but being the luck i have i am sure I will need alot more work done..[img]i/expressions/face-icon-small-disgusted.gif[/img] thanks again quicksilver

 

If you've never had the valves adjusted, get them done asap, valve lash adjustment is just as important as oil changes on a 4 stroke quad motor. Depending on the number of miles you do a year, it should be done once a year.