: WARNING! 4.9L Dayco Tensioner Pulley warning: DO NOT BUY #231081!!!



Hairball
12-03-10, 11:17 PM
I've only owned my 93 Seville for less than 2 weeks and was aware it needed an idler pulley. No problem, 5 minute job. Well, since I live a few blocks from Auto Zone and they always seem to have the lowest local price, I checked and they had an idler pulley for my 93 Seville 4.9L for $18 so I I bought one.

Came home, pulled the old one that had a combination washer/bearing dust cover between the bolt and bearing to keep dust out. I pulled the bolt out with that washer, then simply put it into the new pulley and installed it. So far, so good.

I then started the car and thought "hey, it doesn't seem any quieter!". So after about 5 minutes of checking other pulleys, starting and running the engine, etc I looked down with my MagLite (it's after dark here and I was outside in my driveway) and saw metal shavings not only ON the new pulley, but flying around in the air around it!

I pulled back into the garage and removed the new tensioner pulley (discovering the bolt was already loose after a few minutes!) and discovered that the OEM washer/dust cover was not designed for the aftermarket pulley and therefore was actually rubbing ON the pulley itself!!! Yes, I was pissed! I checked the old one and it was fine, no rubbing. I quickly discovered that the aftermarket Dayco #231081 tensioner (although the same physical dimensions) was NOT going to work unless I removed the washer that keeps dust out of the bearing!!!

So, this is your early warning: do NOT use Dayco p/n 231081 Tensioner Pulley unless you're willing to remove the factory washer.

I'm NOT happy right now, and have decided to let Dayco know on Monday what I think of their designs.

Just wanted to warn other owners of a 4.0L who might be needing an Idler Pulley: do NOT buy a Dayco 231081 or you'll be very sorry!

drewsdeville
12-04-10, 12:40 PM
Yeah, all of the aftermarket pulleys are the same. Someone else posted the same experience just a few weeks ago.

Whats really strange is that years ago I ordered one from an AC Delco parts distributor I have a hookup with, and it had the same incorrect pulley shape that doesn't work with the factory washer. So apparently, even if you go AC Delco, you will need to remove the washer.

Hairball
12-04-10, 01:24 PM
Yeah, all of the aftermarket pulleys are the same. Someone else posted the same experience just a few weeks ago.

Whats really strange is that years ago I ordered one from an AC Delco parts distributor I have a hookup with, and it had the same incorrect pulley shape that doesn't work with the factory washer. So apparently, even if you go AC Delco, you will need to remove the washer.

That's good to know for future reference and so others are warned. :thumbsup:

Since I've turned wrenches for over 35 years I should have noticed the difference, but I couldn't really see very good (didn't use my drop light) while my neighbor held the breaker bar for me while I quickly replaced the pulley. I just pulled off the old one, put on the new one and replaced the bolt with the washer still on it. Maybe I should have taken the old one off and held them side by side to see if they looked the same. Lesson learned! (But I feel like an idiot for not noticing it first.)
:mad::bigroll::banghead:

Belt Man
12-16-10, 11:04 AM
I would like to apologize for your inconvenience. My name is Robert Christy and I'm the Director of Marketing for Dayco Products. After reviewing this forum posting and checking the OEM dust cover with our pulley, there is an interference fit. This is not abnormal to some OEM designs and our replacement product. The Dayco aftermarket pulley does not require the OE dust cover for the replacement. Instructions on the back of the pulley box states, "This replacement pulley has a permanently sealed bearing; therefore the dust cover is not required".
I hope this helps clear up some frustrations for your members. Please feel free to call me directly with any questions. 918-481-2370.
Happy holidays.

still_walkin
12-20-10, 06:55 PM
yea i never used one but when my old caddy needed one i saw they are made of thermo plastic and the original is made of metal i got a used one off ebay for 15 dollars . it came from a 87 sdv but it was for a 86 sdv . ran like a champ. good luck

cadchris
12-21-10, 03:19 PM
I notice this thread posted under my thread and had the same issue with a Gates Tensioner for my 91 Eldo. that looked to be a totally different design.....
http://www.cadillacforums.com/forums/ht4100-4-1-4-5-4/217968-bad-c-delco-waterpump-91-eldo.html

I wish I had it installed at that time but the body of the tensioner looked so different and narrow in design.

My OEM tensioner failed and I took it appart to find out why its spring sprung. And the round spring had actually fractured and had a small line of rust within the coil break. I took photos and sent all my questions to Gates and they said this was common because water gets into these old OEM style tensioner's and starts to rust the springs where the Gates Tensioners are totally sealed (bearing and body). Also the Gates design is a lot narrower which spooked me and also does not use the factory washers ect when intalling..............I think my year had the washer dust cover but now I can't remeber but it was mentioned by Gates. The OEM bolt was sticking out so you would see a lot more thread with the narrower design tensioner which looks a little goofy but its just more threads to crank the nut on.

Here are some good tutuorials on Tensioner designs and upgrades flat spring vs. round spring ect.....

I kind of think the Gates is a better sealed design than the Dayco and uses a better spring but the bottom line is if you have the original tensioner, "Replace It" with an updated design because it will cause a lot of headaches which is what I'm thinking was my problem with my new Delco Water Pump failing but I'm going to run it by Dayco and Gates to see if they could rationalize it.

I remember Gates explaining that these new generation tensioners are a 1 time replacement and should last many times longer than the original design. So this instance, this part should be replaced with an aftermarket upgrade!

Gates:
http://www.gates.com/index.cfm?location_id=4766

http://www.gates.com/brochure.cfm?brochure=4956&location_id=544

Dayco: Video
http://www.rockauto.com/catalog/moreinfo.php?pk=960334

Hope this helps,

chris