Darius Rudis
Supporter
OOPS, You do have a point (V-belts). This is my first V-belt since using them in the 1980's... DOH!
My current setup (in construction, not driving phase - yet):
Squealing V-Belts
- Thread starter Rod Dittmar
- Start date
My current setup (in construction, not driving phase - yet):
Rod Dittmar
Supporter
OK Guys,
WOW! Much appreciative of all the suggestion for trying to resolve this issue. I think while I've got the thing apart and have access to everything, I'll scuff some pulleys, use some Door-Ease, and install a couple of new belts. Fingers crossed.
Thanks to this Forum and especially all of you who responded with tips & tricks.
Rod
WOW! Much appreciative of all the suggestion for trying to resolve this issue. I think while I've got the thing apart and have access to everything, I'll scuff some pulleys, use some Door-Ease, and install a couple of new belts. Fingers crossed.
Thanks to this Forum and especially all of you who responded with tips & tricks.
Rod
Rod Dittmar
Supporter
Ian, I think so. I'm using Gates automotive ribbed V-Belts and the alloy pulleys are from CNC & Sanden. I believe pretty much all standard stuff. The bottom of each pulley's 'V' appears shiny new, while the sides show scuffing which tells me that the belts are riding the sides.
Rod
Ian Anderson
Lifetime Supporter
How big is your alternator? It takes about 1 hp to generate 25 amps in an alternator.
And an old rule of thumb was a normal V Belt is good for around 5 hp
So if you are running a 100 or 120 amp alternator you are at max possible with a V Belt
Ian
And an old rule of thumb was a normal V Belt is good for around 5 hp
So if you are running a 100 or 120 amp alternator you are at max possible with a V Belt
Ian
Devin
Supporter
Rod, also make sure you are measuring the v groove of each pulley that they are the same and getting the appropriate width and style of belt. Most of your box parts stores don’t know anything about the parts they stock BTW…ask me how I know. My local AC repair shop put a wrong belt on my after-dealer installed air conditioning on my ‘66 Mustang and squealed like heck and started to wear the edge off with only a few miles on the drive home. Well I had to fix their “repair” that I paid them to do by getting the right belt.
How to Identify a V-Belt?
A V-belt is a wedge-shaped belt manufactured out of a rubber compound, reinforced with a tensile cord specifically engineered to transmit power into movement. V-belts can be found in driving mechanisms, such as engines in air compressors, fans, and pumps.
megadynegroup.com
Check this sight out for some v belt differences. I agree that the GY Gator belts will be the best quality ones that are readily available.
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The Goodyear gatorback belts are very good - high recommend.
As Ian said above, v-belts are different widths. In other words, the v-belt width has to be matched to the pulley groove width. If they're mismatched then they won't run right -noisey, come off, wear too fast, slip, etc.
As Ian said above, v-belts are different widths. In other words, the v-belt width has to be matched to the pulley groove width. If they're mismatched then they won't run right -noisey, come off, wear too fast, slip, etc.
Bill Kearley
Supporter
Jerry, The starter, if it cranks your motor over the block must have ground thus the grounding of the alternator would be good. I mentioned it in the way I did after I read post # 6
Lee Patterson
Supporter
Rod - did you get resolution on this? I have a "chirp" from my belt at startup
Bill Kearley
Supporter
Best of the season Randy
I mounted a good size hydraulic pump on a 3406 Cat engine and used a back idler ( couple of sealed roller bearings mounted beside each other.) for belt tensioning with no problem.
Pully wrap is very important !!
I mounted a good size hydraulic pump on a 3406 Cat engine and used a back idler ( couple of sealed roller bearings mounted beside each other.) for belt tensioning with no problem.
Pully wrap is very important !!
Rod Dittmar
Supporter
I've tried pulley re-alignment, new belts, tightening, loosening, belt dressing, etc. but still get an occasional squeal. This usually only happens on a cold startup, but sometimes even when warm. I just never know. Mostly an annoyance, and I've pretty much learned to live with it. If it ever becomes more problematic, I may look into those Jones Racing products.
Howard Jones
Supporter
I have a sugestion. But first a bit of info I got from Powermaster when I called them and asked to talk to a engineering type not a sales person. I wanted to know what the maximum RPM the alternator was designed for. Not the engine PM but the alternator itself. We talked for a while about that but in the end he was abe to tell me that theirs were good up to about 15000 RPMs in NEW condition.
So if you have a engine with a rev range of 3K to 6500 RPM and a pulley ratio of nearly 3 to 1 (common for a alt pulley) then you will kill the alternator in a track car. My problem was the alternators in my car were dieing with various kinds of death.
I also asked him what was the oprimum RPM range for charging purposes given my rev range and he said if you ran the alternator in your track car at 1 to 1 it would be perfect. I ultimaly went with a 6 ihch crank pulley and a 4 1/2 inch diameter alt pulley to accomade idleing on the pit lane. No problems since.
How does this relate to our cars? Many street setups seam to have a pretty small alt pulley in relation to the carnk pulley. This means at 5500 engine rpm I bet your alternator is very close to its rev limmit and certianly out of optimum charging range. The cheaper the alternator the slower it needs to be spun to live. The really cheap ones are not really good for much above 10K rpms. They are ment to charge minivans at idle for hours.
Also I think in this case the squeak is the little pulley contact area on the alt. being overcome and slipping by the much larger area of the crank pulley that is driving the system.
Find a 4 inch diameter alternator pulley and give it a try. The alternator will certainly like it. Unless you spend nearly all the time well below 2500 rpms.
So if you have a engine with a rev range of 3K to 6500 RPM and a pulley ratio of nearly 3 to 1 (common for a alt pulley) then you will kill the alternator in a track car. My problem was the alternators in my car were dieing with various kinds of death.
I also asked him what was the oprimum RPM range for charging purposes given my rev range and he said if you ran the alternator in your track car at 1 to 1 it would be perfect. I ultimaly went with a 6 ihch crank pulley and a 4 1/2 inch diameter alt pulley to accomade idleing on the pit lane. No problems since.
How does this relate to our cars? Many street setups seam to have a pretty small alt pulley in relation to the carnk pulley. This means at 5500 engine rpm I bet your alternator is very close to its rev limmit and certianly out of optimum charging range. The cheaper the alternator the slower it needs to be spun to live. The really cheap ones are not really good for much above 10K rpms. They are ment to charge minivans at idle for hours.
Also I think in this case the squeak is the little pulley contact area on the alt. being overcome and slipping by the much larger area of the crank pulley that is driving the system.
Find a 4 inch diameter alternator pulley and give it a try. The alternator will certainly like it. Unless you spend nearly all the time well below 2500 rpms.
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Rod Dittmar
Supporter
Thanks Howard,
Definitely something to consider and maybe try in the future in order to protect the alternator. My squeal is usually only on a cold start up. After a minute or two there's no problem. The car is also a street car only and, almost embarrassed to say, I don't think I've ever had the engine revving over 4K RPMs (can't speak for my wife on that when she drives it). Anyway, the noise inside the car at that point is so loud that my eardrums will give out before the alternator ever does...
Definitely something to consider and maybe try in the future in order to protect the alternator. My squeal is usually only on a cold start up. After a minute or two there's no problem. The car is also a street car only and, almost embarrassed to say, I don't think I've ever had the engine revving over 4K RPMs (can't speak for my wife on that when she drives it). Anyway, the noise inside the car at that point is so loud that my eardrums will give out before the alternator ever does...
As H.J. suggested, going to a larger alternator pulley will reduce the alternator drag torque and probably reduce or eliminate the squealing. You will lose charging below about 1500 rpm, but if you have a good battery it shouldn't effect real-world driving.
David Miller
Supporter
Large pulleys should have a 40 degree angle, alternator pulley should be at 38 degrees. If you have the squealing belts you took off, take pictures of the side walls. Let's see where the wear pattern is.