Adding Zerk to mandrel

[Syncro]

I will take it to another shop next week. I was thinking rod bearing too....

Update on the noisey engine.

I was going to take it in to another shop, but after the weekend of the Fourth the lawn really needed cutting so I just said heck with it and ran the mower anyways. I mean if it was a bad rod than it was more than likely not economically feasable to fix. Well.... to my great surprise the engine fired up and the noise was GONE!! To make matters even more confusing I just ran the machine tonight for an hour and same thing, quiet, powerful rumble and not a clack, clatter or knock to be heard. Now either I'm going nuts or there is something strange going on here.

Any ideas? There is obviously something loose in there somewhere, but what? That knock sure sounded seriouis, like a rod bearing or other heavy component, I am at a loss how it could just stop.

Regarding the original thread, the mandrel is still running smooth, so I guess at least some grease made its way into the bearings.

 

[John47]

Have you checked the cowl to see if it's loose and all the other pieces of sheet metal that direct air to all parts of the engine?? Sounds like something is loose and catching either the flywheel or some other part.

Also, I've never had any trouble getting B&S parts, even for older engines and I've rebuilt many older B&S engines.

I've found some mandrels were fitted by the manufacturers with grease nipples! I replaced the mandrels on an older Murrey, the old ones were sealed, the new ones had zerks on!

 

[HomeBrew2]

If it's intermittant, you might get new head gaskets and pull the heads to de-carbon the heads, piston tops and valves. I have to do that every few years as under certain conditions it will sound like the motor is trying to hammer itself apart. No carbon, no noise. Just a thought ... it's easy and cheap.
Cheers!

 

[Syncro]

If it's intermittant, you might get new head gaskets and pull the heads to de-carbon the heads, piston tops and valves. I have to do that every few years as under certain conditions it will sound like the motor is trying to hammer itself apart. No carbon, no noise. Just a thought ... it's easy and cheap.
Cheers!

Thanks for the tip. I didn't think carbon build up could cause such a loud knock, wonder how that happens. One thing that I have always done since the machine was new is run it at about 1/3 throttle, very seldom wide open. so maybe that can cause carbom buildup. In any event, since it is an intermittant problem and it has not blown itself up yet, I assume no harm is being done running it. I'll try full throttle next time I mow and maybe blow out excess carbon. I used to do that with my old Ford years ago.

John47-
I did check the cowl, etc, but this is not a sheetmetal noise. It sounds internal, I was certain it was a rod bearing before it dissapeared. A loose rod wouldn't fix itself, so the mystery continues.

 

[HomeBrew2]

... In any event, since it is an intermittant problem and it has not blown itself up yet, I assume no harm is being done running it.

Well, yes and no. If it is carbon, and if you can keep it from doing it, then you're probably ok. If it's carbon, when you hear the noise the motor is preigniting/ detonating, which should eventually pound a hole in the piston