Not another Knocking post....

[Fodder]

Hi All,

I've got a new noise that's shown up and I'm worried about what it might be. Here's a video clip to explain better than I can [YOUTUBE]f9VZTyfsSe4[/YOUTUBE]It sounds as though it's coming from the alternator side and I will try removing the belt next time I'm up at the boat to try to isolate the problem. I have discovered that I have been using the 'wrong' oil and put 5w30 in as opposed to SAE30. I can't see that being the only cause, but would like to hear your thoughts. Please let me know if you have any thoughts.

Thank you in advance,

Fodder

[Loki9]

Yeah, that sounds bad. Try pulling one spark plug wire at a time while the engine is running to see if the sound changes.

[Mo]

pull the belt and see if it changes

Can't say that I've heard that one before. What is your oil pressure saying?? You might just get lucky and that might be accessory drive related. I haven't heard one sounding like that but, hey, it's right there though.

Main thing here is to take a deep breath and trouble shoot that beast. Take the alternator belt off and see if it changes. The engine is noisy, no doubt about it. I'd be running 15w40 Rotella (shell) in that.

[Fodder]

Thanks for the quick reply and the tip on the video post. That was step 1. :-) . I had changed the spark plugs the week before so may be something related to that.

[ndutton]

I had changed the spark plugs the week before so may be something related to that.

Doesn't hurt to be doubly sure the firing order is correct.

[Mo]

How did this noise start. When did you notice it and any circumstances surrounding the onset of the noise. Also, have a look at the wires and see if one is contacting the alternator blades as it turns...sometimes one contacts and chaffs, then continues to arc and does make a ticking sound.

[Fodder]

I've noticed a slight noise in the past but it's been very pronounced since changing the plugs. The engine wouldn't start a few weeks back and I changed the plugs as part of my troubleshooting (turned out to be the electronic ignition wire had pulled out). I've just saved the Moyer firing order pic and will be double-checking that 1st thing. I hope it's something as simple as that....

[Loki9]

Sounds a lot like this one: http://www.moyermarine.com/forums/showthread.php?t=5352

I hope it's something else.

[Mo]

Ensure correct plugs
Ensure plugs tight
Check firing order of wires
Check wires for chaffing
..if nothing there remove the alt belt and try it.
..and 15w40 is wonderful stuff, you won't be sorry.

[Mo]

Lokie,

Re the video you linked...I don't think it's the same noise. That is a deep knock in the link you put on there. I remember following Jim's repair. I think this particular problem is a wire or something associated with the accessory drive. Hopefully it will be that easy.

[Fodder]

I happened to have the oil in the garage from the oil-change on the weekend and just ran it through a fine mesh filter. Luckily there was no metal filings or residue in the oil at all, so that's a positive development. I'll head to Crappy Tire and get some 15w40 and do another change this weekend after checking the plugs, firing order and alternator. Whew! Oh, fun, fun, fun. Thank you again for all your thoughts and suggestions.

[Mo]

Here it is. Accessory Drive 99.27% (heh heh) certain. Although the sound is different that just means a variant stage of failure...the ticking is there. You will need to take the alt belt off and see if it changes...if so call Ken at MMI and ask him to see and listen to your video. I`m thinking accessory drive because it`s right on that side. Ken can also set you up with parts.

http://www.youtube.com/watch?v=dzs4pYEQE4U&feature=channel_video_title/engine

You can repair it in the boat. So here`s what I would do. I`d go to the boat asap and do the checks. One thing at a time then run the engine and check for changes...at this point I`d remove the alt belt first. Once the problem is located, call Ken and order what you need. That will shorten your down time. If it is the accessory drive, you can likely use the engine to get on and off the dock until parts arrive. I,d change that oil too. Might be related...

[Fodder]

Thanks Maurice. I went and grabbed a jug of Rotella T 15w40 this morning based on your recommendation. It says diesel on the jug, though. Is this the right stuff? I'm about to give Mike a call and see if he'll have a look at the video, too.

[sastanley]

Fodder...you have received excellent suggestions. The key is to be methodical with your troubleshooting. Try the easy stuff. One thing that is great about this forum is we don't always agree but respect each other's opinions, so I am gonna throw out a different order of the things I'd do than Mo based on your report (and not seeing the original video..):

First, The type of oil is not critical at this juncture, let's fix the noise problem, since it is new. The P.O. of my boat ran 10w30 Mobil 1 for years in the engine. I switched back to SAE 30, but will likely try 15w40 on the next change. You are not hurting the engine presently with 5w30 in it. Also, there is no problem using the 15w40 Rotella in a gas engine..it is formulated as a heavy duty diesel truck oil, but I used it in a 4.0L Jeep engine for years and liked it just fine. I run Rotella 5w40 synthetic turbo diesel oil in my slightly hopped up Civic project car.

Second, since you changed plugs recently, double check the plug wire/firing order and look for any chaffing as Neil & Mo suggested. Running it in the dark will help noticing any "arcing" of chafed wires.

Third, Once you've confirmed the firing order and plug wires are correct, I'd try Loki's suggestion of pulling one plug wire at a time & re-inserting and moving to the next..you should notice a distinct difference in the way the engine runs, but it should continue to run. If you pull a wire and there is no change or a more significant change than the others, you've found at least one problem. I've had new spark plugs be no good in other motors and chased my tail for weeks, until I finally pulled the bad (brand new) plugs.

Fourth, pull the alternator belt to unload the accessory drive.

one more tip - Using a mechanic's stethescope, or even a screwdriver with a long blade as a substitute & up to your ear & placing it on the individual components to isolate, can help with pinpointing an unknown noise...watch out for spinning belts & pulleys while doing this!

[ndutton]

Someday we ought to talk about auxiliary drives, their wear and what causes it. This thread might end up being the place, we'll see.