87 trx 250 Fourtrax Rod Knocking or Wristpin?

[RollTideAL]

I have a 1987 fourtrax 250 with a slight metal to metal knocking sound in the head when at idle. I took the head apart to check the rod but found no play in it. The wristpin also seems to be fine. There is no up , down looseness I can find that would cause the knocking. Any idea? The knocking is only heard at idle and sounds like metal to metal slapping. Like a rod knocking but not as loud or hard.Not a tapping like a cam chain more of a slapping of metal. As far as I know the engine is all stock with maybe new rings.
Thanks for any Info.

[tomgodd]

Man I am not real sure except maybe also check valves. You did not mention that and I am not there to here it. I know of a site that I mod at that is alot more active you could check out.
Its www.hondaatvforums.net
Don't forget us here though. I mod on both forums. You may get some more answers there. Look me up.

[trx2fiveO]

I'm going to agree with tom you might need a valve adjustment

[RollTideAL]

Hey, I checked the valve adjustment before I broke down the motor hoping that was it, but it was set right plus the knocking was more in the bottom end. I think the previous owner checked the valves too. They were set right on .007 mm . Let me ask you guys this: Should the wristpin have any play in it? Thank you for reading and trying to help. I know its hard to tell someone what the problem is without being there, but yall give me new ideas as to where to look.

[tomgodd]

I would say no!

[trx2fiveO]

Check your Decompression lever adjustment if you have one? is this a 250X? and does it have a backup kickstart or pull rope?

[mdopole]

I had that on mine when I rebuilt it. It turned out to be the valves. Make sure you put it on the right mark when you adjust them theres a "t" then an "f" notch on the flywheel and another "t" 180 out. put it on the "t" thats before the "f". . It still ran decent but when I adjusted them properly it was night and day! Until my intake valve stem broke......haha

[mud99]

If its coming from the bottom end you may have a rod knocking. The wrist pin should not have any play in it or you would be getting piston slap You may also want to look at the wrist pin to see if the lock rings are still in place

[RollTideAL]

Ok. Sorry for the late,late reply. I got it back together. I honed the cylinder, new rings, and timing chain. It run great. I'm thinking the timing chain had more play than I thought and was hitting the head. I did put a new wristpin in it which got rid of the little play I was having. I still have one more problem I think. Do they always run so hot? We were riding them in the woods and at a idle I heard a hissing sound. I turned it off and the sound was coming from the gas tank. When I open it the gas was boiling. We now have 2 of these 4wheelers a 87 and 85 both get hot like this. What do you guys think could be causing this or is this normal?

[Jbaddog675]

i have a 87 honda fourtrax 250, brand new stator, now when i kick it over it kicks back like its out of time? any ideas on what i could try? have already torqued the valves and checked the timing chain