Intermittent Whine

[Don Moyer]

Hanley, with the noise now being a light clatter, it looks like you might have the offending beast cornered to where the side load test might once again prove useful. If the clattering is really your (apparently lightly damaged) idler gear, a side load should snug it up enough to at least modify the clicking sound.

[hanleyclifford]

OK, went out and ran the engine and whining noise still present, actually more like a squeal. Changed oil to 15w-40 diesel. Did not solve the problem but made the rest of the engine quieter so I began listening with a wooden dowel. Got the loudest and most definite signal where the yellow circle indicates. Could this just be an old fashioned water pump bearing-packing-up-problem? Tomorrow I will go back out with my Oberdorfer backup and run a test. Edit: the MM 502 has about 1200hrs (no maintenance).

[Mo]

Hi Hanley,
I've never had one apart... I'll park my ears and mix a drink. Good luck with that. It's quite likely you noticed it before it got too bad.

[jpian0923]

That's good news.

[hanleyclifford]

That's good news.

I am cautiously hopeful. Does anybody know what the recommended interval is for replacing the MM 502 bearings? I guess I sort of thought they were indestructable.

[Dave Neptune]

Longevity

Hanley, I have not seen a recomendation on waster pump bearing replacement intervals but my best guess if your findings are correct it's 1200 hours or so.

Hope this is the fix.

RE the magnetic chips. Any engine with those kind of hours and a pan as large as the A-4 will have many chips and pieces of sacraficed, warn and oh KRAP (like what bevelled the gear ) kind of filings in it. The vibration of the engine will magnetize most metals to a certain minor extent. The gears pull a lot of oil past them and keep things stirred up in the pan. To see a few bits klinging to the gear would seem normal to me on an engine like these. That small chamfer on the edge of the gear is in my humble opinion no biggie. Did you ever try dragging a magnet inside the pan to see what all it gathered. I had many people in the past using magnetic oil plugs and or tips on there dip stix panic when they saw bits of metal. At that time I would explain that some is normal and don't worry until it is a bunch and they become noticebly chunkier.

Dave Neptune

[jpian0923]

Magnetic oil plug and dipstick...what a great idea. I just stuck a big magnet on my oil pan...I thought I was a genius for doing that.

[sastanley]

I installed a magnetic oil pan drain plug on my wife's Audi...fortunately, I have not seen any large metal shavings..yet.

For the Atomic 4, a magnetic dip stick would seem cool...since many of us don't actually drain it like a car, stuff getting sloshed around might stick to the dip stick if it were magnetized.

[jpian0923]

Wishlist item???

[Mark S]

Changed oil to 15w-40 diesel. Did not solve the problem but made the rest of the engine quieter . . .

Okay, I'll bite. Can anyone explain this? Is it the 40, the diesel, or some other variable dependent on brand and additives that can't be quantified?

Mark

[Mo]

Check this tread for oil types...its a start.

Hi Mark,

Read through this thread and there's lots of info on oil. http://www.moyermarine.com/forums/sh...highlight=type

[Mark S]

Mo,

I remember that thread and I remember another one in which Don mentioned motorcycle oil and SG rated oils as they related to the reversing gear. Here I just wondered whether something particular about the oil Hanley added made the engine run more quietly, or whether the quiet could be attributed to a number of other things. It seems to me the engine should sound the same whether the oil is 30 weight or 40 weight so long as there is sufficient oil each time that isn't too dirty. Am I wrong about that?

Mark

[Mo]

Hi Marc,
It's basically the thicker viscosity that makes it quieter. I normally run 15W40, however, in June of this year I changed the oil but put 30 weight in. I immediately noted it was noisier...nothing ominous, just louder running. Last week did my oil change and put 15w40 diesel oil back in. I normally change my oil every 20 hours (25 hrs this past change) and it stays clean.

When I hear less noise that means there's more oil up around those moving parts. Reversing gear etc all works fine with it also. One thing is for sure, these engines never ever had the quality of oil on the market today.

[hanleyclifford]

Culprit Identified

Once again Hanley has been found guilty of overlooking the obvious. Went out and put in the Oberdorfer backup and the whining is gone. I will send the MM 502 to Moyer Marine for analysis and rebuilding and it will become my spare. Tomorrow I'll be on the phone to Ken to order a new MM 502 to become the primary. Note in the picture that there is no wear to the housing and only scant wear to the cover plate. The impeller is intact except for a few particles - this after 1200 hours of pumping antifreeze half way around the boat! When I ran with the Oberdorfer today I immediately noticed I was running 5 degrees hotter. The rest of the analysis will be done at Moyer Marine. Both Mo and Neil get the gold stars for making the call. Thanks to all for input and making me learn how to do YouTube. Edit - I just noticed that Bill also asked about the water pump.

[smosher]

Looks way too clean, maybe it needed some grime