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1965 Oldsmobile Jetstar 88: When I brake, the car pulls strong to the left!
I have a 1965 Oldsmobile Jetstar 88 convertible.
When braking, the car pulls strong to the left. All drum brakes, probably standard. The left front brake brakes very well. The right front brake brakes poorly. About 20% of the power of the left.
We have already replaced (on both sides) the brake hose, brake cylinder, brake shoes, brake drum and master brake cylinder. Nothing improved at all.
Air came out when bleeding the front right brake. So the line seems fine, my mechanic says.
Does anyone have an idea what the problem could be?
We suspect the Brake Distribution Block. Maybe something is clogged. Or the lines are incorrectly connected or swapped over.
Could it be? Also: Is that the original part for my Jetstar 88 in the picture? Or maybe a wrong part.
Thanks for the help and greetings from Germany.
Last edited by steve-kartoffel; January 28th, 2022 at 10:07 AM.
Perhaps the return springs are shot on one side? Another is possibly the backing plates on one side have a deep gouge where the brake shoe touches it and is preventing one of the shoes from moving adequately? Another problem could be they are not adjusted correctly?
If the car goes hard left without the steering wheel following the pull it may be a rear brake problem. If the wheel suddenly goes left and the car also goes left it is most likely a front brake problem.
The distribution of braking force should be equal to both front wheels and equal to both rear wheels. Front to back can be compensated through metering devices but LF and RF should be identical. LR and RR should be identical. These statements assume the system is still plumbed/routed correctly.
Can any temperature difference be found between L and R? A hot wheel is a sticking/grabbing wheel. A cold wheel is a lazy/non-working brake.
Occasionally a brake drum can have too much material cut away which increases the diameter but reduces the contact surface area on the shoe. This could be ruled out by swapping drums from side to side.
What master cylinder is on the car, one fluid reservoir or two?
first: a temperature difference cannot be determined. The car behaves in the same way when it is warm and when it is cold. The master cylinder (see photo above) is a fluid reservoir.
thank's for the Tipps. I just spoke to my mechanic. He said: He had vented several times. If there was air in it, it came out powerfully. If he then opened the bleeder nipple again afterwards, the brake fluid also came out powerfully. This suggests that there might not be a problem in the lines after all.
Nevertheless, the car pulls strongly to the left when braking.
The braking values from the test bench are: 200 Newtons at the front right and 800 (!) Newtons at the front left.
could it be that the problem is not too little braking power on the right but too much braking power on the front left???
first: a temperature difference cannot be determined. The car behaves in the same way when it is warm and when it is cold. The master cylinder (see photo above) is a fluid reservoir.
thank's for the Tipps. I just spoke to my mechanic. He said: He had vented several times. If there was air in it, it came out powerfully. If he then opened the bleeder nipple again afterwards, the brake fluid also came out powerfully. This suggests that there might not be a problem in the lines after all.
Nevertheless, the car pulls strongly to the left when braking.
The braking values from the test bench are: 200 Newtons at the front right and 800 (!) Newtons at the front left.
could it be that the problem is not too little braking power on the right but too much braking power on the front left???
Not sure what test bench means, how did he measure the 200 and 800 newtons? If that's fluid pressure then it's a problem with a clogged or crimped (crushed) line or it's possible that one of the new brake hoses is defective. Two options replace the brake hose again on the side with the weak braking, or unhook all the steel lines and hoses on the front and blow air through them to see if they are clogged. Then refill and rebleed the entire system. It's also possible that one of the steel lines is rusted internally and plugged, you can also replace the front hard lines, if you can't easily blow air through them.
I think what a previous person said about one side getting hot, was that you could tell if it's front or rear that is unbalanced by comparing the temperature of one side vs the other after a few hard stops from reasonable speed. Take off the hubcap before you drive. Then after the few hard stops, pull over and immediately feel one side with your hand and then the other, both front and rear. If braking is so uneven you will be able to tell the difference. If the left front is hotter than the right front then you know it's the front wheels. If the left rear is hotter than the right then you know it's the rears.
Last edited by sysmg; February 2nd, 2022 at 06:07 AM.
Originally Posted by steve-kartoffelView Post
The braking values from the test bench are: 200 Newtons at the front right and 800 (!) Newtons at the front left. Exactly what does that mean? Is that hydraulic line pressure, or something else?
The specified values (200 on right side and 800 Newton on left side) are the usual measured values from a brake test bench here in Germany. The brake test stand is a plate embedded in the floor. You drive up there at walking speed. And if you're on the plate you have to make an strong braking stop. The plate then measures the force with which it is pushed forward. I don't know how braking power is checked in the USA.
Does anyone know what the usual Newton readings for the brake should be? My mechanic said the 800 Newtons is way too much. And the 200 are more of a normal value. It's a bit confusing...
The specified values (200 on right side and 800 Newton on left side) are the usual measured values from a brake test bench here in Germany. The brake test stand is a plate embedded in the floor. You drive up there at walking speed. And if you're on the plate you have to make an strong braking stop. The plate then measures the force with which it is pushed forward. I don't know how braking power is checked in the USA.
Does anyone know what the usual Newton readings for the brake should be? My mechanic said the 800 Newtons is way too much. And the 200 are more of a normal value. It's a bit confusing...
There is no similar test here in the US, so we can't give you comparable numbers. Brake force depends as much on tire friction as braking capability, so that test is really only useful for determining relative side-to-side braking, not an absolute value. If one side is too high (which I find difficult to understand), perhaps THAT'S the side with the problem. It almost sounds like the high side is locking up, which could be caused by contaminated brake linings or some other problem.
Ok, thanks for your answer. Yes, the values at least show that the power ratio from the front right to the front left is not correct. Incidentally, this brake test is standard in Germany, since you have to drive your car to the TÜV (technical inspection association) every 2 years. And you can't drive without their certificate.
I would check the adjuster on the side that is pulling. If it doesn't move freely, it could be sticking with the pads too close to the drum. Dies it pull when driving as well?
Also check that the springs inside the the drum aren't binding on something. They need to move freely to bring the pad away from the drum after releasing the pedthe. Check both sides, you could have the side opposite the pulling not engaging firmly enough due to binding.
They used to perform that type of brake test in NJ as part of the annual inspection when I was a kid. Don't know if they still do as I've been gone since 1978. I would make sure the lines are bled again. Was there any brake fluid contamination on the shoes?
They had a mobile set up here in Ontario and would randomly set up on the side of the street and pull over a car that would look a little shabby and make them test their brakes on the device. If your brakes were even and actually worked then you got a pass and drove away. When I saw this set up I pulled in with my fairly new '64 Chebby and was told to go away because it was too new.
Ok, thanks for your answer. Yes, the values at least show that the power ratio from the front right to the front left is not correct. Incidentally, this brake test is standard in Germany, since you have to drive your car to the TÜV (technical inspection association) every 2 years. And you can't drive without their certificate.
We have this in Sweden also , most cars must have this approved once every 14 months or you don´t can use the car.
( subaru and cars with similar 4wd do not have to do this test) cars 30 - 50 year old every 2 years. Over 50 years = no need.
But we don´t have Newton , poor video quality but shows the brake test. It is always intresting to look at the needels on the gauge showing left and right
wheel when they do this test.
@ oldcutlass NJ is ONLY a documents review and emissions test. The emissions test is done every two years on cars over 5? years old by scanning at the ALDL. No trouble codes, it passes. Cars over 25 years old are exempt and do not get inspected at all, no window sticker is issued.
There are no other aspects safety related or not.
Remember when they even checked headlamp alignment?
@ oldcutlass NJ is ONLY a documents review and emissions test. The emissions test is done every two years on cars over 5? years old by scanning at the ALDL. No trouble codes, it passes. Cars over 25 years old are exempt and do not get inspected at all, no window sticker is issued.
There are no other aspects safety related or not.
Remember when they even checked headlamp alignment?
Hello CGH, thanx for your pics. But I suppose, I dont understand your description as well. Is it possible, you write based on this photo with the the numbers 1 to 4, what each pipe is for. Thanx
In your other thread I indicated I don't believe the distribution block is your issue (as did Joe).
When the vehicle is moving down the road at ~80 kph does the vehicle consistently steer in a straight line with no brakes applied?
Is the steering wheel aligned in the center?
It stands to reason if the left side has greater pressure (800 Newtons = 180 pounds force) than the right side (200 Newtons = 50 pounds force), the left side is four times stronger than the right side yielding a serious pull to the left.
It's going to be one of two things: (1) Either the left side is applying far too much force (compared to the right side); or, the right side is not applying enough force to be equal to the left side. I think the majority of factors which can influence brake force are not hydraulic — but instead mechanical. I would review the installation and functioning of each mechanical part you replaced - brake cylinders, brake shoes, brake drums.
I would re-inspect the installation of mechanical hardware.
Last edited by Vintage Chief; February 3rd, 2022 at 06:48 AM.
Reason: wrong URL; updated
In your other thread I indicated I don't believe the distribution block is your issue (as did Joe).
I would re-inspect the installation of mechanical hardware
Don´t think the block causes the issue either , but should be intresting to read what the problem is.
Hello, ok, now we suppose, the block is maybe not the problem....
But we check, whether the outgoing lines are at the right outputs on the block.
One more time: That's just a block of brass with four interconnecting holes in it. Use a little common sense. It DOESN'T MATTER which lines are connected to which holes. They are all equivalent in flow and pressure. There is no internal valving.
And, as you have previously stated - when the brakes were bled powerful streams of brake fluid shot from the bleeding port. Therefore, brake fluid pressure is not the issue.
Incorrect assembly of mechanical parts is most likely the issue, etc.
My guess from afar is that one drum/ shoe has gotten fluid on it. Front or back. Once soiled, it's almost impossible to clean good enough to keep from pulling to one side, and will always throw/ pull the steering. Did this happen when the new brakes were installed or before also.?.. Tedd
Hello, we also had the assumption and subsequently exchanged all parts (brake shoes, brake drums, etc.). Everything is clean, no brake fluid on it.
Could maybe the following cause the problem? The car was retrofitted with an Airride. i.e. Air bladders instead of feathers. In addition, the car has knock-knees, i. H. the tires rub off on the inner surfaces. However, both sides of the vehicle are roughly the same. So toe and camber doesn't seem to be well adjusted.
While a poor alignment can contribute to pulling one way or another, I'd check to make sure the shoes are installed properly. There is a primary and secondary shoe, the lengths are different.
Hi. Problem is fixed! The car brakes correctly again! It's almost embarrassing... On the left front side, the brake parts (cylinders, shoes...) have NOT been replaced. However, I had assumed that. Now my mechanic has replaced these parts. The front left brake cylinder was defective. He has two bolts. However, only one of them worked. Namely the one to the shoe of the leading brake shoe. This is how this high braking value came about. Now the braking values on both sides are the same again. I'll drive to the TÜV in the next few days and hope to get the sticker. Thanks to all of you for the numerous tips and hints.
January 28th, 2022, 10:05 AM
