Superdave's 65 Impala SS 5.3 Swap
07-24-2015, 08:38 AM
#401
TECH Senior Member
iTrader: (7)
Dave,
One thing you haven't discussed, and thus I assume you haven't checked is runout, both lateral and axial. You need to make sure that the rotor is flush against the axle flange and that it is centered. If the rotor is not flush, it will do a slight figure 8 wobble, and if it is not centered it'll cause a mild out of balance condition. I made some videos of this that I will post up in a bit.
Andrew
One thing you haven't discussed, and thus I assume you haven't checked is runout, both lateral and axial. You need to make sure that the rotor is flush against the axle flange and that it is centered. If the rotor is not flush, it will do a slight figure 8 wobble, and if it is not centered it'll cause a mild out of balance condition. I made some videos of this that I will post up in a bit.
Andrew
07-24-2015, 02:27 PM
#402
TECH Resident
Thread Starter
Dave,
One thing you haven't discussed, and thus I assume you haven't checked is runout, both lateral and axial. You need to make sure that the rotor is flush against the axle flange and that it is centered. If the rotor is not flush, it will do a slight figure 8 wobble, and if it is not centered it'll cause a mild out of balance condition. I made some videos of this that I will post up in a bit.
Andrew
One thing you haven't discussed, and thus I assume you haven't checked is runout, both lateral and axial. You need to make sure that the rotor is flush against the axle flange and that it is centered. If the rotor is not flush, it will do a slight figure 8 wobble, and if it is not centered it'll cause a mild out of balance condition. I made some videos of this that I will post up in a bit.
Andrew
Took a test drive (always the same route/time/distance) and I am excited to say that the problem is gone. There was the slightest bit of squeak a time or two when first applying the brakes, so I will take it back apart this weekend and file a tiny bit more....but I think I found the problem. Before I filed, I could hold the rotor hard against the flange and it would rock slightly side to side, but not up and down. After filing it doesn't rock anymore.
Man what a nightmare. This car has been sitting through MONTHS of nice weather....all because of a tiny bit of metal.
07-25-2015, 05:48 PM
#405
TECH Senior Member
iTrader: (7)
Funny that you mention this today, as today's project was to check for a bent axle or a mounting issue at rotor/flange. I detected a very slight wobble in tire while moving (on jack stands), and so my next step was to take the rotor off and check everything there before buying a new axle. When i took it off, I could see some freshly worn metal at the little hub that sticks out of the flange, and a corresponding scar on the inside of the hole at the center of the rotor. I took a file to the protruding area, probably knocking off less than a millimeter, but enough to ensure the rotor could go on flat.
Took a test drive (always the same route/time/distance) and I am excited to say that the problem is gone. There was the slightest bit of squeak a time or two when first applying the brakes, so I will take it back apart this weekend and file a tiny bit more....but I think I found the problem. Before I filed, I could hold the rotor hard against the flange and it would rock slightly side to side, but not up and down. After filing it doesn't rock anymore.
Man what a nightmare. This car has been sitting through MONTHS of nice weather....all because of a tiny bit of metal.
Took a test drive (always the same route/time/distance) and I am excited to say that the problem is gone. There was the slightest bit of squeak a time or two when first applying the brakes, so I will take it back apart this weekend and file a tiny bit more....but I think I found the problem. Before I filed, I could hold the rotor hard against the flange and it would rock slightly side to side, but not up and down. After filing it doesn't rock anymore.
Man what a nightmare. This car has been sitting through MONTHS of nice weather....all because of a tiny bit of metal.
That is awesome. That 1mm get magnified significantly as you move away from the center. Look everything over very carefully as it takes very little to cause big problems. As you said, the rotor should not rock at all when you slide it over the wheel studs and hold it against the axle flange. Make sure that the O.D. of the axle flange is small enough to slide easily inside the rotor hat. Don't be afraid to put a little chamfer all the way around the outer lip of the axle flange, because the rotor may have a matching fillet in the hat. Post some pictures of all that stuff!
Andrew
07-25-2015, 09:27 PM
#406
Superdave's 65 Impala SS 5.3 Swap What do you have for a proportioning valve? Or any valves in the brand system? some factory style valves. have a centering valve that when centered equal brake pressure and if fluid pressure is lost the valve moves to the side with less pressure from greater pressure on the other side. It's designed to keep the brakes working. I've had issues with bleeding and after fixing the problem getting this valve to self center again can be a pain. You can bleed one half but the other half won't bleed. And you have horrible pedal.
When these valves move they like to stick cuz they have had years of junk buildup inside the bore of the valve. You can un stick them by stomping on the pedel with the opposite end bleeder open.
When these valves move they like to stick cuz they have had years of junk buildup inside the bore of the valve. You can un stick them by stomping on the pedel with the opposite end bleeder open.
07-26-2015, 02:42 PM
#407
TECH Resident
Thread Starter
Dave,
That is awesome. That 1mm get magnified significantly as you move away from the center. Look everything over very carefully as it takes very little to cause big problems. As you said, the rotor should not rock at all when you slide it over the wheel studs and hold it against the axle flange. Make sure that the O.D. of the axle flange is small enough to slide easily inside the rotor hat. Don't be afraid to put a little chamfer all the way around the outer lip of the axle flange, because the rotor may have a matching fillet in the hat. Post some pictures of all that stuff!
Andrew
That is awesome. That 1mm get magnified significantly as you move away from the center. Look everything over very carefully as it takes very little to cause big problems. As you said, the rotor should not rock at all when you slide it over the wheel studs and hold it against the axle flange. Make sure that the O.D. of the axle flange is small enough to slide easily inside the rotor hat. Don't be afraid to put a little chamfer all the way around the outer lip of the axle flange, because the rotor may have a matching fillet in the hat. Post some pictures of all that stuff!
Andrew
What do you have for a proportioning valve? Or any valves in the brand system? some factory style valves. have a centering valve that when centered equal brake pressure and if fluid pressure is lost the valve moves to the side with less pressure from greater pressure on the other side. It's designed to keep the brakes working. I've had issues with bleeding and after fixing the problem getting this valve to self center again can be a pain. You can bleed one half but the other half won't bleed. And you have horrible pedal.
When these valves move they like to stick cuz they have had years of junk buildup inside the bore of the valve. You can un stick them by stomping on the pedel with the opposite end bleeder open.
When these valves move they like to stick cuz they have had years of junk buildup inside the bore of the valve. You can un stick them by stomping on the pedel with the opposite end bleeder open.
Car stops ok...it's just a little less than I would expect from 4 wheel disc brakes. It's not impossible that I still have a little air in the system, but I can address that.
07-26-2015, 09:38 PM
#408
TECH Senior Member
iTrader: (7)
I drove it for a longer drive today. Probably 6 or 7 miles there, and then the return trip as well. Still had very faint chirps, but only for a few seconds and only 4 or 5 times total. This still tells me that there is an issue though, so I will take it apart again and file a little more. I am afraid to take TOO much off the hub or rotor though.....won't that make it more and more difficult to center exactly on the axle if it's not snug there?
Andrew
07-26-2015, 09:43 PM
#409
TECH Resident
Thread Starter
Supposed to rain all day tomorrow and I don't have wheel wells in the car yet, so my next test drive will be Tues. Pretty confident that I finally knocked this thing out now.
07-27-2015, 10:59 PM
#410
TECH Senior Member
iTrader: (7)
After rereading what you wrote, I got it. The center hub is where I had the extra metal imperfection that I had to file off. I did hit the edge of the flange with the file today, and I also found another little bump on the flat of the flange too. I murdered it with the file.
Supposed to rain all day tomorrow and I don't have wheel wells in the car yet, so my next test drive will be Tues. Pretty confident that I finally knocked this thing out now.
Supposed to rain all day tomorrow and I don't have wheel wells in the car yet, so my next test drive will be Tues. Pretty confident that I finally knocked this thing out now.
Andrew
07-28-2015, 03:19 PM
#411
TECH Resident
Glad to hear this is improving for you. There is no reason you shouldn't have great brakes on a vintage car.
You should be able to lock them up at will and with confidence in your pedal (it isn't soft).
I hated the brakes on my truck until I went to an oversized master (1/1/4" diameter) with a hydroboost unit.
Doug
You should be able to lock them up at will and with confidence in your pedal (it isn't soft).
I hated the brakes on my truck until I went to an oversized master (1/1/4" diameter) with a hydroboost unit.
Doug
07-29-2015, 01:31 AM
#412
TECH Resident
Thread Starter
Ugh. Took a much longer trip today, probably 25 miles round trip, with a short break in the middle. The noise returned a few times but it was very quiet and barely noticeable. However, for the last 10 or 15 minutes, the noise had returned very noticeably, and it was loud enough to cause concern. I am going to do as Andrew suggested and bevel the outside of the axle flange. If that doesn't work, I GUESS I either have a warped rotor or a bent axle.....but I don't understand why either of those would give me problems only SOME of the time.
Took it up the street later in the evening to get ice cream (maybe a mile and a half). Not a peep out of it.
I guess if all else fails I can buy the stuff to convert it back to rear drums....but I really don't want to do that.
Took it up the street later in the evening to get ice cream (maybe a mile and a half). Not a peep out of it.
I guess if all else fails I can buy the stuff to convert it back to rear drums....but I really don't want to do that.
07-29-2015, 07:50 PM
#413
TECH Resident
Do you own an IR heat gun? The harbor freight one is maybe $30.
I find it a very useful tool for troubleshooting anything to do with temps. I kept one in the glovebox while debugging my truck.
Take temps of the 4 rotors and compare, fronts are usually hotter and side to side should match. That one might have overheated and warped.
Given the rubbing you are describing, I'd bet it is heating up and warping a bit and causing the squeak.
Is the overall braking performance better?
Doug
PS - I use that IR temp gun for measuring radiator / thermostat housing temps, condenser temps, AC vent temps, trans cooler / trans pan temps, rear end temps, tire temps, etc. etc. anomalies can be found very easily with that tool.
I find it a very useful tool for troubleshooting anything to do with temps. I kept one in the glovebox while debugging my truck.
Take temps of the 4 rotors and compare, fronts are usually hotter and side to side should match. That one might have overheated and warped.
Given the rubbing you are describing, I'd bet it is heating up and warping a bit and causing the squeak.
Is the overall braking performance better?
Doug
PS - I use that IR temp gun for measuring radiator / thermostat housing temps, condenser temps, AC vent temps, trans cooler / trans pan temps, rear end temps, tire temps, etc. etc. anomalies can be found very easily with that tool.
07-30-2015, 12:48 PM
#414
TECH Resident
Thread Starter
Do you own an IR heat gun? The harbor freight one is maybe $30.
I find it a very useful tool for troubleshooting anything to do with temps. I kept one in the glovebox while debugging my truck.
Take temps of the 4 rotors and compare, fronts are usually hotter and side to side should match. That one might have overheated and warped.
Given the rubbing you are describing, I'd bet it is heating up and warping a bit and causing the squeak.
Is the overall braking performance better?
Doug
PS - I use that IR temp gun for measuring radiator / thermostat housing temps, condenser temps, AC vent temps, trans cooler / trans pan temps, rear end temps, tire temps, etc. etc. anomalies can be found very easily with that tool.
I find it a very useful tool for troubleshooting anything to do with temps. I kept one in the glovebox while debugging my truck.
Take temps of the 4 rotors and compare, fronts are usually hotter and side to side should match. That one might have overheated and warped.
Given the rubbing you are describing, I'd bet it is heating up and warping a bit and causing the squeak.
Is the overall braking performance better?
Doug
PS - I use that IR temp gun for measuring radiator / thermostat housing temps, condenser temps, AC vent temps, trans cooler / trans pan temps, rear end temps, tire temps, etc. etc. anomalies can be found very easily with that tool.
Today I took the rotor to a friend at a shop and he resurfaced it for me. It was definitely warped. I am about to button the car back up again but I may not get to test drive it again until tomorrow.
Overall braking I am still not thrilled with. I am going to borrow one of those doodads that bleed the lines in reverse instead of out through the bleeders in the traditional way and see if that helps release any tricky air bubbles.
08-01-2015, 01:55 PM
#415
TECH Resident
Thread Starter
Finally got to drive the car today. No squeaking at all. However after my short trip, the rotor temperature on the trouble side was low compared to the other side rear. I assume this means that the brakes on the newly resurfaced rotor are doing less work than the other side, meaning that the stupid Cadillac caliper adjustment needs to be tweaked. I will do that in a little while and test drive again.
Rotor temps after 12 minute drive:
LF 170
RF 173
LR 197
RR 140 (original bad wheel)
Rotor temps after 12 minute drive:
LF 170
RF 173
LR 197
RR 140 (original bad wheel)
08-01-2015, 02:05 PM
#416
no pics.? WTF. lol
08-01-2015, 02:43 PM
#418
Have you tried Swapping rear rotors side to side to see if the noise moves with it. And on the off chance are they slotted and drilled? If drilled check the holes for cracks. Also the direction of the slots if directional are not cleaning them self out dust may be setting trapped and making noise.
How did you bed them in?
As a side note. I never use that combination valve anymore. An adjustable rear and full tilt on the front..
The war was not won in a day. But by winning small battles and moving forward.
Keep your head in it and push.
How did you bed them in?
As a side note. I never use that combination valve anymore. An adjustable rear and full tilt on the front..
The war was not won in a day. But by winning small battles and moving forward.
Keep your head in it and push.
08-01-2015, 02:51 PM
#419
TECH Resident
Thread Starter
Swapping rear rotors side to side to see if the noise moves with it. And on the off chance are they slotted and drilled? If drilled check the holes for cracks. Also the direction of the slots if directional are not cleaning them self out dust may be setting trapped and making noise.
How did you bed them in?
As a side note. I never use that combination valve anymore. An adjustable rear and full tilt on the front..
The war was not won in a day. But by winning small battles and moving forward.
Keep your head in it and push.
How did you bed them in?
As a side note. I never use that combination valve anymore. An adjustable rear and full tilt on the front..
The war was not won in a day. But by winning small battles and moving forward.
Keep your head in it and push.
08-02-2015, 05:49 PM
#420
TECH Resident
Thread Starter
Took the car out again today. Didn't travel far from home but made several laps so it wasn't a super short trip. Stopped at a friend's house to pick him up about 12 minutes into trip. When i got to his house, all the rotors were pretty even, 155-170 degrees of so.
Drove another 20 or so minutes and I could hear that dreaded, intermittent chirp again. It was quiet, but it was there. Stopped to check temps again but the thermometer had some kind of malfunction. Dropped the friend off, then went home. Thermometer somehow fixed itself, and the rotor temps were reasonable, but still, the (previously) bad side was significantly cooler than the (previously) good side. If I remember right it was like 140 on the RR, and like 170 on LR.
I decided to take apart the driver's side and see if there was some kind of issue there like I found on the passenger side before. Rotor was very tight and took a lot of banging to remove. I lightly filed any areas I thought might be trouble spots, and added a small bevel around the axle flange. But overall, I didn't see anything strange on the driver's side.
It's POSSIBLE that a tiny bit of chirping could have been coming from the driver's side all along and I couldn't hear it over the passenger side. I really have no idea. While driving, I can't say for sure what side the noise is coming from now because it's a lot quieter. The fact that the driver's side is the one heating up now leads me to believe that there is/was an issue on BOTH rear wheels. Ugh.
I really don't know what else to do. I ordered some higher quality ceramic pads, thinking maybe the cheaper pads I got with the kit have been compromised with all the heat and uneven wear and whatever else. Everything except for the axles has been addressed so I am running out of ideas here.
Drove another 20 or so minutes and I could hear that dreaded, intermittent chirp again. It was quiet, but it was there. Stopped to check temps again but the thermometer had some kind of malfunction. Dropped the friend off, then went home. Thermometer somehow fixed itself, and the rotor temps were reasonable, but still, the (previously) bad side was significantly cooler than the (previously) good side. If I remember right it was like 140 on the RR, and like 170 on LR.
I decided to take apart the driver's side and see if there was some kind of issue there like I found on the passenger side before. Rotor was very tight and took a lot of banging to remove. I lightly filed any areas I thought might be trouble spots, and added a small bevel around the axle flange. But overall, I didn't see anything strange on the driver's side.
It's POSSIBLE that a tiny bit of chirping could have been coming from the driver's side all along and I couldn't hear it over the passenger side. I really have no idea. While driving, I can't say for sure what side the noise is coming from now because it's a lot quieter. The fact that the driver's side is the one heating up now leads me to believe that there is/was an issue on BOTH rear wheels. Ugh.
I really don't know what else to do. I ordered some higher quality ceramic pads, thinking maybe the cheaper pads I got with the kit have been compromised with all the heat and uneven wear and whatever else. Everything except for the axles has been addressed so I am running out of ideas here.