Belt tensioner question - ZR-1 Net Registry Forums

Corvette95 · 06-12-2020

Got my engine back together last night, - fired up, belt tensioner is jumping around and making a "clicking" noise when it does. It was doing this before I torn the car down. I sent my tensioner to Marc H for rebuild. Belt is routed right and I used a NOS correct Goodyear belt, anything to adjust or check besides then tensioner - I would assume it is the internal tensioner spring? Also, I know the tensioner can be mounted incorrectly - hard to do but possible, mine is installed correctly. Any thoughts

WARP TEN · 06-12-2020

Quote:

Originally Posted by Corvette95

Got my engine back together last night, - fired up, belt tensioner is jumping around and making a "clicking" noise when it does. It was doing this before I torn the car down. I sent my tensioner to Marc H for rebuild. Belt is routed right and I used a NOS correct Goodyear belt, anything to adjust or check besides then tensioner - I would assume it is the internal tensioner spring? Also, I know the tensioner can be mounted incorrectly - hard to do but possible, mine is installed correctly. Any thoughts

I am guessing you may have already done this, but I would suggest a call to Marc since he rebuilt the tensioner. --Bob

lfalzarano · 06-12-2020

The belt MUST be correct length for the tensioner to be in middle of range with no hitting either extreme limit, the stronger spring has much to do with that too. If you can push the tensioner arm by hand the spring is too weak even if the part is new.

Sent from my iPhone using ZR-1 Net Registry

Corvette95 · 06-12-2020

Quote:

Originally Posted by WARP TEN

I am guessing you may have already done this, but I would suggest a call to Marc since he rebuilt the tensioner. --Bob

I sent him an email, thing is, I trust HIS work over mine, but everything seems good on my end other than the tensioner jumping

Corvette95 · 06-12-2020

I couldn't upload a video so I used a hosting site. hope this link works...
https://streamable.com/3ix64s

We Gone · 06-12-2020

I hear some noise when the AC compressor cycles, turn off the AC first than check noise. You can also remove the belt and and see what you hear. wont hurt anything as long as you just start check and shut off.

Dynomite · 06-12-2020

What is gap between belts compressed by Tensioner??
Maybe a shorter belt would help??
I think the tensioner jumps around more with a longer (more loose) belt where the pressure applied by the tensioner is less as the tensioner is unwound and the tensioner being pointed directly perpendicular to the belt.

The belt appears too long as the tensioner has deflected the belt considerbly.

secondchance · 06-12-2020

Corvette95. Have you replaced alternator lately? If so, verify if the alternator pulley is correct size. Often, L98 pulley is on replacement. If so, belt ends up being a tad longer and could result in tensioner bouncing around.

Corvette95 · 06-12-2020

I have been checking, belt is correct application, I took a stethoscope to all the bearings including a/c, noise abnormal noise other than the tensioner. I measured the alternator pulley (this was the alternator that was on it when I bought it - I had it rebuilt while it was off just in case) , was suggested may be an undersized pulley, it is 2.4 inches wide (alternator pulley) . I can pry on the tensioner to keep it from jumping around and the noise goes away. https://streamable.com/ahuq0d

Dynomite · 06-12-2020

Belt is too long

06-12-2020	#1
Corvette95 Join Date: Jan 2006 Location: Decatur, AL Posts: 1,107	Belt tensioner question Got my engine back together last night, - fired up, belt tensioner is jumping around and making a "clicking" noise when it does. It was doing this before I torn the car down. I sent my tensioner to Marc H for rebuild. Belt is routed right and I used a NOS correct Goodyear belt, anything to adjust or check besides then tensioner - I would assume it is the internal tensioner spring? Also, I know the tensioner can be mounted incorrectly - hard to do but possible, mine is installed correctly. Any thoughts __________________ Corvette95 Registry and Forum (*************) 1989 C4 Conv Wht/Gry Auto Hardtop Top Flight SOLD 1995 C4 Coupe Purple/Blk 6 Speed 1989 C4 Conv Wht/Red Auto SOLD 1996 C4 Conv Black/Tan Auto SOLD 1994 C4 Coupe Wht/Blk SOLD 1995 C4 ZR-1 White/Gry #278 Dual Dunn Head SOLD 1986 C4 Coupe Black/Red 4+3 SOLD 1990 C4 ZR-1 Red/Red #0454

06-12-2020	#3
lfalzarano Join Date: Feb 2011 Location: Clayton, North Carolina Posts: 1,133	Re: Belt tensioner question The belt MUST be correct length for the tensioner to be in middle of range with no hitting either extreme limit, the stronger spring has much to do with that too. If you can push the tensioner arm by hand the spring is too weak even if the part is new. Sent from my iPhone using ZR-1 Net Registry __________________ Lou[COLOR="Red"][B][SIZE="4"][/SIZE][/B][/COLOR]

06-12-2020	#5
Corvette95 Join Date: Jan 2006 Location: Decatur, AL Posts: 1,107	Re: Belt tensioner question I couldn't upload a video so I used a hosting site. hope this link works... https://streamable.com/3ix64s __________________ Corvette95 Registry and Forum (*************) 1989 C4 Conv Wht/Gry Auto Hardtop Top Flight SOLD 1995 C4 Coupe Purple/Blk 6 Speed 1989 C4 Conv Wht/Red Auto SOLD 1996 C4 Conv Black/Tan Auto SOLD 1994 C4 Coupe Wht/Blk SOLD 1995 C4 ZR-1 White/Gry #278 Dual Dunn Head SOLD 1986 C4 Coupe Black/Red 4+3 SOLD 1990 C4 ZR-1 Red/Red #0454

06-12-2020	#6
We Gone Join Date: Apr 2004 Location: ATL. GA. Posts: 2,163	Re: Belt tensioner question I hear some noise when the AC compressor cycles, turn off the AC first than check noise. You can also remove the belt and and see what you hear. wont hurt anything as long as you just start check and shut off. __________________ Steve 1990 Steel Blue/Black #2355 1990 Red/Red #1473 1991 Quasar /Black #118 Sold 1991 Turquoise/Black #766 Parted Out 1993 Yellow/White #179 Sold 1990 Black/Gray #1361 Headers/4:10s Sold

06-12-2020	#7
Dynomite Join Date: Aug 2009 Location: South Dakota/California Posts: 3,790	Re: Belt tensioner question What is gap between belts compressed by Tensioner?? Maybe a shorter belt would help?? I think the tensioner jumps around more with a longer (more loose) belt where the pressure applied by the tensioner is less as the tensioner is unwound and the tensioner being pointed directly perpendicular to the belt. The belt appears too long as the tensioner has deflected the belt considerbly. __________________ Left Clickable links -Solutions- LT5 Modifications/Rebuild Tricks Low Mileage ZR-1 Restoration 1990 Corvette (L98) Modifications LT5 Eliminated Systems LT5 Added Systems LT5/ZR-1 Fluids 1995 LT5 SPECIFIC TOP END REBUILD TRICKS Last edited by Dynomite; 06-12-2020 at 05:33 PM.

06-12-2020	#8
secondchance Join Date: Aug 2006 Location: McLean, VA Posts: 3,708	Re: Belt tensioner question Corvette95. Have you replaced alternator lately? If so, verify if the alternator pulley is correct size. Often, L98 pulley is on replacement. If so, belt ends up being a tad longer and could result in tensioner bouncing around.

06-12-2020	#9
Corvette95 Join Date: Jan 2006 Location: Decatur, AL Posts: 1,107	Re: Belt tensioner question I have been checking, belt is correct application, I took a stethoscope to all the bearings including a/c, noise abnormal noise other than the tensioner. I measured the alternator pulley (this was the alternator that was on it when I bought it - I had it rebuilt while it was off just in case) , was suggested may be an undersized pulley, it is 2.4 inches wide (alternator pulley) . I can pry on the tensioner to keep it from jumping around and the noise goes away. https://streamable.com/ahuq0d __________________ Corvette95 Registry and Forum (*************) 1989 C4 Conv Wht/Gry Auto Hardtop Top Flight SOLD 1995 C4 Coupe Purple/Blk 6 Speed 1989 C4 Conv Wht/Red Auto SOLD 1996 C4 Conv Black/Tan Auto SOLD 1994 C4 Coupe Wht/Blk SOLD 1995 C4 ZR-1 White/Gry #278 Dual Dunn Head SOLD 1986 C4 Coupe Black/Red 4+3 SOLD 1990 C4 ZR-1 Red/Red #0454

06-12-2020	#10
Dynomite Join Date: Aug 2009 Location: South Dakota/California Posts: 3,790	Re: Belt tensioner question Belt is too long __________________ Left Clickable links -Solutions- LT5 Modifications/Rebuild Tricks Low Mileage ZR-1 Restoration 1990 Corvette (L98) Modifications LT5 Eliminated Systems LT5 Added Systems LT5/ZR-1 Fluids 1995 LT5 SPECIFIC TOP END REBUILD TRICKS Last edited by Dynomite; 06-12-2020 at 06:52 PM.