Need some direction, waterpump on my 86' iroc failed (305 carb, 5 speed with air) and replaced with a new Summit high flow. After putting it all back together I was getting a knocking and squealing on start up. Shut it down thinking the new waterpump failed but i decided to remove all belts and check to see if knocking goes away and it did....so not engine problem. Installed powersteering belt, still no knocking, so waterpump appears to be okay. Installed alternator belt and the knocking and squealing starts up, so take alternator out and the pulley spins okay but has a really slight noise when i spin by hand. Decide to install a new Summit alternator 140 amp since my stock one wasn't really keeping up well when air is on and stereo system. New powersteering belt was also installed as it looked like it could use replacing, alternator belt looked good but decided to replace it as well. Start it back up and still knocking and belt squeal when tapping throttle. Decide the hell with it, drive it and see what happens once warmed up. knock appears to go away, squeal only when tapping throttle. Decide to pin the throttle and it squeals like a pig...........I am lost, just can't figure out what the hell is wrong, any ideas??

 

When you said "knocking" , and that it went away with belt removal , yes indeed most folks would naturally think of bearings in either the water pump , alternator , power steering pump , or any other device being driven from the belt .

But now it sounds as if with a new water pump , new alternator , and can I assume any idler pulleys are ok ? that they haven't fixed it , you really only have two possibilities that come to mind , ok maybe three ;

#1 , one of your new devices are defective , happens more that you'd want to believe , especially in these days of super cheap parts from overseas that are cheap due to the elimination of such frivolities as "Quality Control" .

#2 , one of your brackets holding one of your devices to the front of the engine has cracked , and allows the belt to go loose during situations of high load (like when you "pin" the throttle) .

Or , as a last outside guess , could something be SO loading down your alternator as to cause it to put excess load on it's drive belt , causing the belt to slip when the throttle is opened ?

PS , You didn't mention checking the bearings for the AC clutch , did you ?

 

Thanks I will take a closer look at the alternator bracket. I cleaned the pulleys, I wiped down the new belts just to make sure there was nothing on them, checked alignment, deflection looks good, not too tight and not sloppy, there is no idler pulley......previous owner had an aftermarket ac put in......everything was running great until the waterpump went bad and then my troubles started after installing the new pump and putting everything back on. Absolutely bizarre.

 

I had a knocking sound on my T/A when I bought it. Did some investigating and it seemed to be coming from the smog pump area. Swapped out the smog pump and the knocking has not returned at all after six months. On the old smog pump, the internal bearings must have went out. With the belt off, grab the smog pump pulley and yank ha and pull on it hard. If you get any movement, the bearings are shot. Hope that helps.

 

Any chance that you used different bolts for the alternator pulley that are too long and hitting the water pump casting?

 

Thanks and sorry for the delayed response......car has been stuffed in the garage and untouched since......frustrated as hell with it and busy at work so no time to screw around with it trying to fix this mess. I will likely be back at it around the holidays and take all of your suggestions to see if they correct the problem. Very frustrated that replacing the waterpump has caused me this grief and missed driving it......if it wasn't bad weather it was lengthy waits for parts and repairs.

 

The larger than stock alternator may be too much for drag for the belt. I had nothing but problem with alternator belt squeal on my 86. Swapped to serpentine, Canadian smog pump delete pulley, Powermaster alt..... and like magic - no more problems at all. Best modification ever.

GD