2003 C5 Corvette Coupe LS1 serpentine belt keeps slipping back a rib
I have replaced tensioner and idler pulleys when I replaced this belt and it continues to transfer toward the engine. It’s only trying to skip on the harmonic balancer and tensioner pulley, everything on the driver side is seated well and working. When taking a straight edge to the tensioner pulley it appears the balancer is 1/4 inch out of alignment (toward the radiator) and I see a bit of wobble. Is the balancer cooked or am I missing something?
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if it keeps happening, then you definitely have a pulley out of alignment. I don't think it was much of a problem on the C5 but I think the C6 was known for having balancer problems.
Oh, they are
The problem is bigger on C5s than LS2 C6s.
C5 and C6 both use bonded balancers that are prone to failure. I bought this Vette used with 136k miles and I have no clue what is original or has been replaced.
The LS1. cars are famous for the harmonic balancer developing a wobble as the elastomer wears out. It has to be replaced, and on the Corvette, It sucks. You have to drop the steering rack to get to it. Look at that the balancer doesn’t seem to be that bad. You might be ab...
I just replaced the idler, tensioner, and belt and it immediately slips. This post is my last Hail Mary to determine if I need to take it to a shop.
The harmonic balancer needs replaced 100%
Needs a harmonic balancer.
The balancer pulley can separate. The outer ring starts to separate
All the pulleys have to be in allignment. Even a little bit is enough to cause problems. You said you've measured some to be out of allignment so that's your problem.
I have no useful input beyond what has already been stated, but I just want to quick comment on your absolute madlad balls of steel with putting your hand right in line with that belt, lol. I know the odds of a catastrophic belt failure at that exact moment are slim, but losin...
Courage is a convenient scapegoat for ignorance.
Check the rubber inside the balancer, it may be starting to crack/seperate
A bearing going bad can cause this. Happened with an Accord water pump. The belt kept tracking like that, and then the bearing noise manifested. AND I left it go long enough that the pulley was obviously leaning. And still the seal held
...the belt is torn in this video. Of course it's going to slip. Look at 3.53, 5.77, 6.06, 6.64, etc.
It’s the first thing I noticed on that video. You can see it flapping around the whole time.
Pulley is slightly out of whack.
Get a straight edge and find out what pulley is out of alignment
Check the alignment and adjust it
Something's out of alignment.
I had this happen on a Nissan 350z. I had to replace the power steering pump. This was the only warning before it went out.
What idler tensioner did you use? Most of the aftermarket idlers are not very good because they don't have access to the tooling that AC Delco used. Because of this, many aftermarket tensioners will generate higher deflection. This is one engine part that you want to pony up s...
I bought a Gates kit from rockauto. Think I should buy AC Delco parts instead?
You need to put a straight edge, like a steel ruler, across the various pulleys and find which one is out of plane. Good luck
Or a laser pointer or laser level
Happened to me, my issue was the idler pulley seized. Had to cop a new one
Pulley is off center or you just need a new one
Having the same problem on my 2019 mustang. Old belt does not slip The new belt does. 😡😡
Paint a line on the front of the balancer and watch for the line to separate indicting the balancer is failing.
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usually one pulley is all it takes to do this. look at pulleys and accessories that have been changed first. p/s, alternator etc. find something flat or straight that will fit down in there and put it across the face of each pulley until you can see the spacing difference of o...
Save yourself a lot of time and money and take it to a mechanic. It looks to me like the tensioner is coming apart.
if it wasnt throwing belts before you changed the idler/tensioner, id replace with an oem unit to see if that fixes it before anything else.
The belt was slipping last November so I replaced the belt, then it started slipping again a couple weeks ago so I parked the Vette, ordered a Gates pulley kit, and replaced the idler, tensioner and belt. This video is right before I replaced the two pulleys and belt. It is st...
Is everything exactly for your year of engine and model of your car? There are different offsets for different cars, even though a firebird water pump bolts up to my lm7 just fine, the belt spacing off of the block isn't the same as the rest
The water pump was replaced right after I bought the Vette in October due to a coolant leak that somehow escaped me on the walk around. I didn’t have time to do it myself so I hired a friend of a friend so the pump very well could be the culprit. I have a mobile mechanic comin...
I had the same problem on my LS2 GTO. Ended up being the alternator. Somehow the bearings in it allowed the pulley to move forward a bit causing the misalignment. The belt lost almost the whole 6th rib just like yours. The good news is that it has to be the alternator, power s...
That belt is loose
Crank pulley is about to split.
Change your belt. Look at the image when yoir video stops.
New belt needed, sure you didnt miss a rib when installing it and that caused it to expand a bit om the inside of the belt and then wanting to migrate towards the engine?
I just replaced the idler pulley, tensioner, and installed a new belt and it is still happening.