this is true and this is not a simple process for me as i work on cars and never worked on bikes too much. So far i have taken all the covers off and inspected the spark plugs, clutch basket, starter, and flywheel area timing chain.Disassemble and inspect.... no way around it.
Just looking at them like that won't tell you anything, you need to remove the valve cover and use a feeler gauge to check the clearance between the camshaft and bucket.ok thanks for all the replies. Checked the intake valves they all look good from the intake chamber, but I know exhaust are more prone to fail from my experience.
well so far drained oil under strain and really didn't see one fragment of bearing or any metals. I mean it still could be a spun bearing.Depending on how loud the "knock" is, I'm going with a spun rod bearing as the culprit. I spun my G4 rod bearing just off idle. Idle is the point of the lowest oil pressure and the bearing can fail at that point - instant knock. I find it hard to believe that piston slap would be the culprit. If you dropped a valve, the engine won't be knocking, it will be misfiring and running piss-poor due to the cylinder having no compression essentially. It may also be a broken clutch basket that's hitting the inside of the case.
First thing to do is pull the oil pan and look for fragments. Next would be to pull the clutch cover. If those look good, then look at the top end.
True but knocking would indicate a visibly bent valve, not just a leaking valve. I mean its no a ticking type of deal its a really loud knock. I tried getting a video but didnt hit record lol, oily hands. Now I cant really get a video because drained oil and coolant.Just looking at them like that won't tell you anything, you need to remove the valve cover and use a feeler gauge to check the clearance between the camshaft and bucket.
Also as sky said check the clutch basket. I've heard of that a few times on here.
Already posted no metal shaving or any contamination in oil or coolant and no fragments in any engine covers.I would drain the oil to look for any shiny stuff floating around. If you do then that's not good
True but knocking would indicate a visibly bent valve, not just a leaking valve. I mean its no a ticking type of deal its a really loud knock. I tried getting a video but didnt hit record lol, oily hands. Now I cant really get a video because drained oil and coolant.
Best bet is checking cylinder leakage I think.
Already posted no metal shaving or any contamination in oil or coolant and no fragments in any engine covers.
ok thanks for the reply. Ill drop the oil pan tonight see if their is any fragments.Just looking at the oil is not conclusive. I couldn't see anything in my oil either. The bearing fragments are big, heavy, and the oil drain passage outside the pan has a lot of nooks to trap the fragments. From your description, everything sounds like a rod bearing pounding the crank. Exactly what I've experienced.
If you bent a valve, that cylinder won't hold compression or fire because the valve would not seal. The engine would knock a bit, but the sound of it running on 3 cylinders would drown it out. Plus once the valve is flattened in the cylinder (if it doesn't lock the motor) the noise will decrease.
Drop the oil pan.
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ok thanks for the reply. Ill drop the oil pan tonight see if their is any fragments.
As far as the first rod closest to flywheel. cylinder 1 I assume the rod has a little play about half a millimeter when moving side to side.
Also I see you had this problem how did you fix it and did you need to buy a new crank or have it resurfaced/polished.
Ok I got it.The flywheel is on the right side as part of the clutch basket. That would be the number 4 cylinder. The rod will wiggle ever so slightly side to side. Enough to feel, but not much more. The number 1 cylinder is on the left side of the motor.
I got my crank repaired by APE in California. Did great work and upgraded it with fluted oil passages and lightening. Cost almost as much as a new crank and took several months though. And I needed a LOT of other stuff to rebuild the motor. I hope I'm wrong on your diagnosis, as it's a big expensive job.
Ok I got it.
As far as spinning rods Ive spun rods in my turbo civic few times but not nearly as loud. Always just micro polished and new bearings good to go as long as rods didn't see too much heat/discoloration and crank still smooth.
My leakdown tester does not fit, spark plug threads are to fine and smaller diameter.
