Author Topic: Can't get alternator belt tight enough (Read 10719 times)

bvolks73 · « **on:** November 21, 2008, 08:57:18 pm »

The alternator belt on my brother's 90 TD Jetta (with AC and power steering) was squealing so he replaced it (along with all the other belts) but the new one is beginning to squeal already. It's tightened to it's limit but it still too loose. Is there anything else a person can do to tighten it more or is a slightly shorter belt the only solution?

JT Turbo · « **Reply #1 on:** November 21, 2008, 11:18:12 pm »

I'd put money on there being a broken or missing a/c compressor mount bolt - most likely the one on the belts side, as opposed to the transmission side. There should be two 8mm allen bolts holding the compressor to the bracket, which act like a hinge as you tighten the compressor tensioner.

Take the air cleaner housing assembly out to give yourself some room to work.

Slack off the alternator tensioner to get the belt off the alt pulley, then unbolt the alternator and move it out of the way. You should be able to see whats happening now. The crank/compressor/waterpump belt gets in the way of dealing with the belts side allen bolt, so slack off the compressor and get the belt out of the way if you have to replace a lost or broken bolt. I find the wrecker is the most probable place to find replacements bolts. You can try a standard 6-point metric bolt but its very hard to get a socket to sit square on the bolt head because of compressor pulley interference.

steve6 · « **Reply #2 on:** November 22, 2008, 05:46:02 am »

IF the A/c Belt is too loose it also makes it so the alternator belt wont go tight enough...(A/C belt tension is maxed, makes the Alternator start off already loose) I'd suggest replacing the a/c belt if it appears loose and the A/c is at its max adjustment...

I'm having a hell of a time keeping these damn belts tight on my car :X its like a never ending adjustment process.

bvolks73 · « **Reply #3 on:** November 22, 2008, 05:53:38 am »

Thanks for the help. I'm going to pull the alternator again and have a look at the AC pump. We just had all that stuff off when he put the new belts on so it should come off fairly easily. If I recall correctly there was something odd about one of the AC bolts but I never thought anything of it at the time.

Quantum TD · « **Reply #4 on:** November 22, 2008, 10:55:05 am »

You should also make sure the pulleys are clean and rust-free. On the alt pulley, they are sometimes made of stamped metal that is prone to rust and pit. When that happens, it will eat away at the side of the belt, making it slip further into the pulley and eat away even more.

jtanguay · « **Reply #5 on:** November 22, 2008, 12:41:02 pm »

i bought a CONTI belt for mine, and when i tried to put it on, it was loose, even at the end of the adjustment... i think it was the wrong belt... i even tried drilling a new hole in the alternator bracket arm up top... still not enough! so i went to cdn tire and brought my old belt with me.. sure enough they had the right belt! installed it and voila! i had to adjust the tensioner wayyyy back.

even OEM parts have their issues :roll: although the CONTI belt i bought for the a/c-crank-wp was much shorter than what was on before, and always requires me to jump it on with some sort of tool, it does work nice.

doesn't take long messing with these V-belts to make a person want to switch to serpentine though!!! :lol:

oh and by the way... my advice is to NOT REMOVE THE AC PUMP!!! i did that by accident once, and getting the bolts to align to re-install it was extremely difficult (had to use one of those pointy tools... forget what they're called.. and there isn't much room to play with on the belt side!!)... you might have an easier time, but you don't need to remove it, therefore possibly saving you time/agony/pain/suffering, etc. :lol: just loosen the bolts, and use the adjustment to loosen/tension the belt.

bvolks73 · « **Reply #6 on:** November 23, 2008, 05:25:50 am »

My brother went to Canadian Tire last night to try to find a shorter belt and this time the guy said there were 2 belts listed for the car and he must have got the longer one the first time. Hopefully that fixes the problem.

mtnbob · « **Reply #7 on:** November 23, 2008, 01:12:16 pm »

I had the same problems with a Napa gold belt, and went to a size that was 1 inch shorter. It was a tight fit but now is working great!!!

bvolks73 · « **Reply #8 on:** December 20, 2008, 05:06:33 pm »

:evil: The new "alternator" belt from Canadian Tire was way too long and way too wide. I think we have the right alternator belt but the problem is with the AC belt being too long. Does anyone have a number for an AC belt on a 90 Jetta TD with power steering?

jtanguay · « **Reply #9 on:** December 21, 2008, 07:27:40 am »

Quote from: "bvolks73"

:evil: The new "alternator" belt from Canadian Tire was way too long and way too wide. I think we have the right alternator belt but the problem is with the AC belt being too long. Does anyone have a number for an AC belt on a 90 Jetta TD with power steering?

the canadian tire belt for the a/c was too long on my car too... the CONTI belt i bought for it was so short that i have to use a screwdriver (or something thin) and turn the crank just to get it on. eventually i think it will stretch out, but my 1.6 is out, and a 1.9 mTDI is going in :twisted: so i'll never know

91 ECO · « **Reply #10 on:** December 25, 2008, 10:31:51 am »

Also check the alternator belt tensioner. My belt would squeal all the time until I noticed that the tensioner bearing was shot. A new sealed bearing solved the squeal.

LoneWolf · « **Reply #11 on:** December 25, 2008, 04:42:28 pm »

Stupid suggestion, but why not just get shorter belts?

My GTD had tension issues and the only way i could stop it squealing was to use smaller belts, which meant i didnt need to use all the adjustment i had available.

Dakotakid · « **Reply #12 on:** December 25, 2008, 10:57:24 pm »

Stick with the Continental belts.
Yes, a little tight to get on, initially. But, once on....for the most part....no problems and long service life.

bvolks73 · « **Reply #13 on:** January 03, 2009, 03:23:38 pm »

Bought a conti-tech AC belt from the local VW place and it went on a little hard but worked and had plenty of room for adjustment. The alternator belt was still a bit too loose so he's just going to buy one a bit shorter. Unfortunately the new AC belt snapped within 15 miles and it definitely was not because it was adjusted too tight.
This is getting really old and frustrating. I'm thinking about getting rid of the AC compressor since we have several non AC motors to get pullies and whatever else we need off of.
We just got done putting it back together after painting it last night so at least it makes a good looking yard ornament since it doesn't look like he's ever going to be able to drive it. :roll:

ezekiel · « **Reply #14 on:** January 03, 2009, 03:34:05 pm »

Look at the pulleys, i bet they're worn, so a brand new belt won't make full contact in the V. And the other probably snapped cause it was too tight, it doesn't really take THAT much to get everything proper if the pulleys aren't worn.

Author Topic: Can't get alternator belt tight enough (Read 10719 times)

91 ECO

LoneWolf