urslooow

While road course lapping at Moroso today my belt shredded up on me, it's not subtle with the engine temp spiking from 218 to 255 and the power steering going. I was lucky enough to have a friend run me to NAPA auto parts to get some dex-cool and a 95" belt. Some really really nice guys help me put it on. It fit tightly (NAPA part # 25-060956)I did one 25 min run no problem. Then I had one guy do a check out drive and he was a real horse's ***, after I did my nice steady safe conservative laps, he told me that he wasn't going to pass (OK me for solo) me and started forcing me to drive real hard, it was an eye opener but after a few laps of this extreme hard braking (felt the ABS kick in) and hard acceleration, the belt came off and was no where to be found! My car sits at Moroso now awaiting a new belt (this happened around 3:30 pm so the parts stores were closed or closing and it's 20 miles to the nearest store). The only thing I did recently was replace the small idler pulley on the procharger with a 3" ,(I guess the old one was about 1.5" and was distorted and not making contact) see my other recent thread -ati pulley problem.
What could be going on here. when we turned the car on after replacing the first belt everything worked the belt looked like it was tracking well (6 ribs). all the appliances were working and the car was cooling well. Was I just running it too hard? Could it have something to do with the new idler pulley? Help

EatRice

Sounds like something is not properly aligned. I would check everything in the belts driveline for proper alignement.

blu00rdstr

I guessed right on the idler pulley thread, I'm going to guess this time that your crank pulley is loosening up (I agree with EatRice).

Just to cover my bases, one more guess. Some belt brands stretch quite a bit and become loose, especially when hot. This happened to me after a few country road accelleration runs. The belt that's worked best for me is a Drive-Rite belt from Kragens. Drive-Rite is made by Dayco, but the real Dayco belt hasn't worked as well. The Gator had the worst slippage in my case ('cogged ribs' = less surface area). I tried another brand (I forget now) and it just kept stretching each time I adjusted the tension (I had two places to adjust tension at the time).

MelloYellow

Belt Alignment or Tensioner problem.

I always keep a spare in the car.

urslooow

I'm going to bring it in to my tuner, but in the mean time if lay off the hard driving (we were really flogging the hell out the car when it came off the second time) should I be OK for a while. My tuner is about 50 min from my house works until 5pm and no weekeends and is often on the road showing his products and with my work schedule it's hard to get there.
I'm on my way to NAPA to get that 95" belt now and then hope that those dudes that helped me yesterday will help again (and hope that the car is OK-it was Corvette Drag Challenge nite last nite after road racing at Moroso). Is there any diagram anywhere that shos how to put this belt on and what the procedure is?

MIKE-C5

Wow you are running a 25-060956....you must have a dual tensioner bracket

You might need to align something.....I had that same problem, my tensioner is .046 off and needs shims.....I dont know how....

Im getting A%A dual tensioner set up

This might help:

http://www.sjdiscounttools.com/laz91006.html

DT

Howdy!

You know, I'm reasonably quick around a track, try to drive constant and smooth - but the PRIMARY goal beyond having fun, learning better technique, improving times is BRINGING THE CAR HOME!

Though I've been pretty much cleared for solo with most clubs, I had a couple of instructors that wanted to push me too hard. Even had one that was saying derogatory things about my Z06! (i.e., "Hmm, I guess I was wrong, though these cars were much faster").

I actually said to a guy "Look, this is my street car, not going to put it into a wall [at Sebring] - if driving beyond my capabilities is how I get checked out, maybe we need to talk to the head instructor". That issue got resolved

I'd say 99% of the people at these events are pretty cool, enthusiasts, etc., but there's a few ****** in the mix, some real smart asses. I actually had a guy in a S2K - and granted he was pretty quick [on stickies] - come up to me in the paddox and say something along the lines of "I guess all that low tech HP isn't a match for my superior skills" - you know, really smirky. I suggested that putting my foot up his xxx would probably make things even, and stomping his narrow xxx into the ground would even be better...didn't notice him around the track the rest of the event

Anyway, NEVER overdrive - unless the instructor wants to sign a document stating they will replace you car for you

OK, back to our regulary scheduled talk about belts

urslooow

Upon returning this am with a new belt 96 1/8" (yes double idlers) I found my friends and we "found" the last belt shredded up under the crank and pulled into the a/c compressor (was a real bitch to get out). We noticied that the second idler pulley run interior to the spring loaded tensioner was toast and was moving all over the place (the bearings had seized and there were ball bearings at the bottom of the engine bay and it was forced off it's hardware defined spin track). I had the old idler (the one that sits above the tensioner and pushes on the belt from the top right of the setup) from the other day, that was distorted that had the same size bearings. The guys tried to take out the two sets of what was left of the seized bearings and put the ones in from the old idler that was just distorted on the outside. One set of the seized bearings were fused and refused to come out after 1 1/2 hrs of trying various methods of hammering, chieseling, sawing, etc. I tried one last run to a large NAPA 35 miles away and got a plastic pulley wheel slightly larger, but we just ran out of time the track was pushing us to get out. So these great guys from a little shop called M &F Motorsports offered to take my car back to their shop in their trailer (along with their racecar) and wait for the part to come from ati in 1-2 days. Not only did they do this for free but the father and supervisor of the operation got his son to drive myself, my wife and my 13 yr old to Southern Miami ( a 2 hr ride, 40 min out of his way)for the price of some gas ($40). I can't believe how lucky I was! a flatbed to go 100 miles would be $500+ not to mention the 3-4 hrs labor they spent with the car includ pushing it and tying it down onto their covered trailer. I just hope the story has a happy ending. SHould I just retire this car from road racing and wait for my z06? Are the repeated full blast accelerations out of type 1 turns too much for an ati car?

runamuk

It just goes to show you that there are still good people left in this world

Good luck, I hope you get your belt straightened out

urslooow

We got the interior (2nd idler wheel) pulley from ATI and now they say that they make larger idlers (3") because they work better and that installing this new pulley will require grinding some "material" off the top of the thermostat housing. They reccomended a 99 1/2" Gates belt (which turned out to be too large, glad we bought a few different ones), we ended up using a 98 1/8". Apparently there is no downside to using as small a belt as possible, but too large a blt will slipSo I got the car running a few days later for a $158 now I have one question....
The car is running OK but the oil pressure is lower than it was before all this crap happened. when cruising at low throttle it used to be 39-40 psi, at idle it used to be 32-35. NOW.... at idle it reads 26 and goes up to 32-34 at cruise speed. There is no oil in engine bay, no oil on exhaust pipes, normal exhaust smoke, no chg in oil level (freshly changed). Is this due to different belts? Look at my siganture see if any of the mods I have done leave any clues, thanks

mdhmi

That's a wonderful testament to the bond that racers have. Those sound like some very special people.

Mark