Thread: TD5 serpentine belt. Dayco vs Conti

Originally Posted by coops71

..... The first thing was the belt. The new Dayco was swapped for the old Conti which has a textured rear surface. Start the car and it's perfect. It looks like I'll be buying a new Conti belt. The Dayco version is identical in size but has a very smooth rear surface. Thought I'd share this experience.

Yes!
Strange that for some vehicles this happens .. so randomly.
Same happened to my Tdi a while ago now.
I used Dayco source locally from parts stores, LR parts places or the big names or whatever.
The Daycos we seem to get here all have this smooth backing.
Went onto Ebay and found a Continental to fit the Tdi so hit the buy now.
Took a while to come, and when it did it was a Dayco, not Conti like I wanted.
I contacted seller and they gave me $10 refund, BUT! the Dayco they sent me had the hatched textured surface. Stopped the screeching straight up.

I know this thread is old but thought I would add my 2 cents worth. I recently compared a Contitech 7PK1801 to a Dayco 7PK1800, both used and from my D2a Td5 with aircon but no ACE. There are some significant differences.

Contitech 7PK1801
Outside Length: 1798mm (measured three times the same length with a sewing tape measure)
Overall Thickness: 5.7mm
"V" Depth: 2.7mm
The outer belt is textured with a cross-hatch and is quite a soft rubber material. The V's are also reasonably soft compared to the Dayco. The belt is overall thicker than the Dayco by 1.5mm

Dayco 7PK1800
Outside Length: 1805mm (measured three times +/- 1mm with a sewing tape measure)
Overall Thickness: 4.2mm
"V" Depth: 1.7mm
The outer belt is smooth and made of quite a firm rubber material. The V's are again quite firm rubber and about 1.0mm shallower than the Contitech which would result in less contact area.

The reason I compared is that I was running the Dayco most recently and it had been squeaking on shut down. The Dayco belt replaced the Contitech about 27,000km ago. I had replaced the belt tensioner (genuine LR), idler pulley (Allmakes) and the airconditioning compressor pulley bearing about 7000km ago but didn't resolve the squeak. My next thought was the harmonic balancer/TD but after inspection, it didn't show any significant movement or clearance. I had bought a new Dayco Powerbond balancer so I fitted it anyway as the original balancer is about 22 years old. This did resolve the squeak, however running the used Dayco belt, the tensioner wobbled like crazy even at higher revs (and yes I do fit my belts back the same way). So I replaced the Dayco belt with another new Dayco 7PK1800 and this resolved the tensioner wobble at revs but there is still a little wobble at idle.

I found a supplier of Contitech 7PK1801 belts in Poland that I may try next.
https://www.ebay.com.au/itm/285735300781

So my TD5 had the textbook TD5 "Sneeze" on stopping. The mechanics were replacing belts multiple times. New tensioner.. nothing really worked. And most recently it had a new belt, and then the ac stopped working. The guys replacing the AC compressor said the belt was in a bad way.. and I said was just replaced. Anyway, then the mechanics said the belt was had it and I said "it's just been replaced".

So, since the new AC compressor. No sneezing. Will be interesting to see if it stops eating belts.

Originally Posted by Captain_Rightfoot

The guys replacing the AC compressor said the belt was in a bad way.. and I said was just replaced.

Sounds like a bearing that is starting to seize up on the AC compressor pulley. Luck the belt didn't break....messy! We have to remember that our beloved vehicles are now getting on to 21 to 26 years old. While it is easy to replace a belt tensioner, the bearings on all the other pulleys are just as old and will all need replacing.