Mystery Noise Cause Discovered

[gary_electric]

Thanks to all who responded to my mystery noise. I've traced it down to a chattering oil pump. I've gotten a suggestion to switch to a heavier weight oil (I currently use 10w40 Castrol) and Power Punch to quiet it down. I notice the noise is much worse upon cold starts. Has anyone ran into this? Is there a reliable fix that doesn't involve tearing down the engine to replace the oil pump?

[feltonminicycle]

I really doubt you could hear your oil pump. It's less than 1" diameter piston. Possibly the chains whipping but I doubt you would hear that either. Many a time the t/o bearing can be heard chattering on the diaphragm spring. It's easy to get to the oil pump though, you don't even have to take out the engine. Just go beyond the clutch and into the primary cover. Sometimes the main shaft bearing drops and oil will start spewing which also makes a nasty noise.
Miles

--- In
2cylinderhondas@yahoogroups.com
, "gary_electric" wrote:
> Thanks to all who responded to my mystery noise. I've traced it down to a chattering oil pump. I've gotten a suggestion to switch to a heavier weight oil (I currently use 10w40 Castrol) and Power Punch to quiet it down. I notice the noise is much worse upon cold starts. Has anyone ran into this? Is there a reliable fix that doesn't involve tearing down the engine to replace the oil pump?

[gary_electric]

Thanks Miles,
If it is the main shaft bearing, would I see an oil leak? I'm not actually having any symptoms other than the noise. It's pretty quiet outside the cabin. I can only hear it if I take a length of hose hold it to the driver's side of the bottom of the engine case below the oil pump, and put the other end in my ear. I did notice that the fellow who did my exhaust managed to not complete one of his welds, leaving a gap, and a subsequent exhaust leak, where the pipe passes under the fire wall. Maybe I'm just hearing normal engine sounds, and the exhaust is the problem? On the subject of oil weight, would you recommend I stay with the Castrol 10w40?

--- In
2cylinderhondas@yahoogroups.com
, "feltonminicycle" wrote:
> I really doubt you could hear your oil pump. It's less than 1" diameter piston. Possibly the chains whipping but I doubt you would hear that either. Many a time the t/o bearing can be heard chattering on the diaphragm spring. It's easy to get to the oil pump though, you don't even have to take out the engine. Just go beyond the clutch and into the primary cover. Sometimes the main shaft bearing drops and oil will start spewing which also makes a nasty noise.
> Miles
> --- In
2cylinderhondas@yahoogroups.com
, "gary_electric" wrote:
> > Thanks to all who responded to my mystery noise. I've traced it down to a chattering oil pump. I've gotten a suggestion to switch to a heavier weight oil (I currently use 10w40 Castrol) and Power Punch to quiet it down. I notice the noise is much worse upon cold starts. Has anyone ran into this? Is there a reliable fix that doesn't involve tearing down the engine to replace the oil pump?