Serpentine squall

[Mark Rinker]

Today a new noise began emanating from under the hood. Thought maybe some grit or gravel from snowplowing had made its way under the hood, but it continually got louder and more consistantly present today. By the time I got home, it was enough to cause me to pop the hood and investigate.

Its 100% coming from the serpentine belt, near the left (of two dual) alternators, possibly from the tensioner mounted below...but...how to tell which one???

How about a can of WD-40 with straw engaged, starting with squirting the tensioner? Then...if not the tensioner, a small burst behind the pulley on the alternator?

What say ye for my test methods to ISOLATE THE SQUEAKER?

[richp]

Hi Mark,

I ignored a similar noise on my '01, and ended up with a fried belt when the tensioner siezed up in the middle of nowhere.

Given that there were more than 125k miles on it at the time, I think now that I probably should have replaced the tensioner pre-emptively when I did the alternator the week before.

FWIW.

[DmaxMaverick]

With the belt removed, you should be able to feel the bad one turning by hand. They should turn smoothly with a little resistance (the grease and seal). If it spins freely and/or makes any noise (like metal roller skates), it's bad. It is, however, good practice to replace all the idlers, tensioner (at least the bearing) and the belt as soon as one fails. Keep the serviceable (not necessarily "good") one(s) and the belt for roadside spares.

If it's an alternator, it should be noisy as well if bad, turning by hand.

Spraying WD40 in there is not a good idea. It'll lubricate the belt, which will cause issues for a long time coming, and probably not tell you anything. It will also sling the stuff all over.

[Mark Rinker]

Thanks for the input. I'm on it today. Probably the tensioner - but unusual at only 85K miles?

[GMC D-Max]

I had the same issue with mine, shortly after I picked it up (with 33k on the odo). First, I found that the alternator (single) was squeaking... pulled the plastic cover off the back of it, and a few drops of oil took care of it. Second was the belt, which was looking a little worn. I put on a Goodyear Gatorback when I added the second alternator, and it's been silent since.

[SoTxPollock]

So Mark, what did you do? I've noticed that I hear a squeek anytime I drive in rain and then park overnight. When it first starts up I hear the squeek, but after a while it goes away. I'm suspecting the bearings are going dry and there probably is a very slight overnight corrosion that gets worn away after that little while. It's been that way now for about a year. I wish there was a way to lube those bearings, but I don't know of any. The guys out here used to add grease to their sealed bearings on the John Deere combines by using a syringe and needle filling it with grease and puncturing thru the seal and injecting the grease, my nephews say they have kept old bearings running for many years by doing that, seems the rubber or neoprene seals seem to reclose after you withdraw the needle. I've never tried it, but they swear it works just fine.

[Mark Rinker]

I threw a tensioner at it last weekend before heading out on an 1800 mile trip to Montana and back.

It fixed the squall but my satisfaction was was short lived. After driving on wet cinder roads in Montana, new serpentine belt squeaks emerged.

Upon returning home today, during a routine oil change I discovered lots of 'dirt road' under the hood in places I have never seen it accumulating on previous trucks...something just didn't look right with the amount of it, and how wet it looks like things had been underhood....

I think possibly some rubber flaps or rubber hood seals were omitted during the reassembly of my truck after the body work last summer.

Questions for 2009 (or similar) truck owners:

Can you shine a flashlight through your grill and clearly see the driver side battery? Air cleaner box on the passenger side? I can!!!
On the underside of the leading edge of the hood, where the external chrome molding attaches, is there a rubber seal that would contact the top plastic radiator/core support cover? Not on my truck...although there are two rubber seals on the both fender tops where the hood contacts?I think the root of the problem squeak/squall problem is too much underhood spray...which is further compounded by snow plow duty which generates its own source of snow/grit mix that is easily sucked into the cooler stack area.

Sorry I can't post pictures here, or I would show you what I am referring to...

[JohnC]

OK, I know what a rain squall is and I've even been caught in one, but I'm really puzzled about this "serpentine squall"....

Do you mean "squeal" (like a pig)?

[Mark Rinker]

Obviously an attempt to describe a sound...(But you knew that.) ;) I'll take some license with definition #2 below... LOL


Definitions of squall (n) (http://www.bing.com/Dictionary/search?q=define+squall&qpvt=definition+of+squall&FORM=DTPDIA)


squall [ skwawl ] http://www.bing.com/s/playbtn.png (http://www.bing.com/caption/image/?bid=fKgX%2fWpsSMJVHA&bn=EDPG&FORM=DTPDIA)

windstorm: a sudden strong wind, often with heavy rain or snow
brief disturbance: a short but noisy disturbance
blow strongly: to blow strongly and suddenly

Synonyms: storm (http://www.bing.com/Dictionary/search?q=define+storm&FORM=DTPDIA), windstorm (http://www.bing.com/Dictionary/search?q=define+windstorm&FORM=DTPDIA), gust of wind, gust (http://www.bing.com/Dictionary/search?q=define+gust&FORM=DTPDIA), tempest (http://www.bing.com/Dictionary/search?q=define+tempest&FORM=DTPDIA), shower (http://www.bing.com/Dictionary/search?q=define+shower&FORM=DTPDIA)

[JohnC]

Obviously an attempt to describe a sound...(But you knew that.) ;)

Actually, I didn't. I was pretty sure you meant "squeal" but not positive. You never said "like a squall" but the term "squeak" did come up several times. Never heard it used that way.

[MikeyB]

My belt was making noise and I changed the tensioner which solved the problem for a month or so. Doing some investigating, I found that my belt (a Goodyear replacement from NAPA) was too long allowing it to on the tensioner. I bought a slightly smaller belt and it solved the problem.

YMMV,
Mike

[Mark Rinker]

Actually, I didn't. I was pretty sure you meant "squeal" but not positive. You never said "like a squall" but the term "squeak" did come up several times. Never heard it used that way.


I think I made it up. :D It was more than a squeal. My brain thought...SQUALL. LOL

[Mark Rinker]

By the way, there were two parts omitted/missing from the reconstruction of my truck...on both sides of cooler stack that allowed water and road grit into the engine compartment.

[JohnC]

I think I made it up. :D It was more than a squeal. My brain thought...SQUALL. LOL

Well, maybe you're a little psychic. I found this secondary definition: "a brief disturbance: a short but noisy disturbance"

More interesting, though is this possible origin:

"The word appears to be Nordic in origin, but its etymology is considered obscure. It probably has its roots in the word skvala, an Old Norse word meaning literally, [get this] to squeal."

[DIESEL/VETTE]

I Replaced The Tensioner Bearing Not To Long Ago And It Is Good Now I Would Like To Replace The Bearings In The Idlers, Does Anyone Have The Bearing Number For The Two Idlers? Thank You For Your Help.

2003 2500hd Duramax.

[Diesel 4me]

Diesel / Vette,

Here you go ... GM part number for idler bearings is 98057284 (2 needed)

Hope this helps :)

[DmaxMaverick]

Be careful with your CA part numbers. The 02-03 CA models are different than anything in the universe. Fed emission trucks didn't have vacuum pumps. There are 2 types of idler pulleys, smooth and grooved. Verify the one(s) you need.

[DIESEL/VETTE]

I just changed the two bearings on my 03, skf #6005 2rsjem. $22.00 ea.

[DIESEL/VETTE]

Forgot to post, both my idler pulleys are smooth.

[crashz]

My 2012 gasser started squeaking after I washed it two weeks ago. It dried and stopped, I washed it again, and started squeaking again. Takes about a full week to diminish. Got an appointment at the dealer tomorrow morning, but some investigation revealed a loose idler. Even with a tensioned belt on it, I can move it slightly by hand.