Groaning Front Brakes

[JohnMc]

just as a thought, you might do video, with audio of course, on YouTube and then post the link here.
Someone probably has had the same problem.

[jandarah]

That's a thought, John, but my foul language might drown out the problem noise

[djape1977]

trw are good quality pads, so look for problem elsewhere.
metal clips that hold pads in place must be tight and there must be springs also, to keep the pads from moving around

[jandarah]

Me again,

Well, I removed the pads again and this time, checked the spring type clips' tension. Well, they were there, but not offering much resistance/tension against the side of the pads. So, I removed the four clips, did a bit of fancy re-bending, replaced them and then the pads. The pads did not want to seat unless they were pushed hard against the spring clips, thereby making a very snug fit. Not able to take it for a run, but here's hoping. By the way, I did notice that the TRW front pads do have a thin rubber shim on them.

Cheers,

[jandarah]

The saga continues....

Took the Spider for a run tonight to get some Thai takeaway (yum). After the earlier re-tensioning of the spring clips, there is definitely much less noise/vibration. But, I can feel the vibration in the brake pedal, as before. No vibration felt through my left foot pushed hard on the floor, only my right foot on the brake pedal.

Following on from that observation, when just outside my gate, on the hill, I switched off the engine and let the car coast. I then applied the brakes, much more effort required, of course, but, guess what, not a scrap of noise or vibration. The car still pulled up ok. One would think that, if the problem was at the discs and pads, then with or without the engine running and the booster working, the noise would still be there?????

What next?? the booster, not enough vacuum, have I been looking in the wrong spot and wasting money on new discs etc??

PS I love this hemisphere difference in time and day. I ask the question as I head off to bed and, all your wonderful responses are waiting for me in the morning.

Very much appreciated.

[DieselSpider]

The saga continues....

Took the Spider for a run tonight to get some Thai takeaway (yum). After the earlier re-tensioning of the spring clips, there is definitely much less noise/vibration. But, I can feel the vibration in the brake pedal, as before. No vibration felt through my left foot pushed hard on the floor, only my right foot on the brake pedal.

Following on from that observation, when just outside my gate, on the hill, I switched off the engine and let the car coast. I then applied the brakes, much more effort required, of course, but, guess what, not a scrap of noise or vibration. The car still pulled up ok. One would think that, if the problem was at the discs and pads, then with or without the engine running and the booster working, the noise would still be there?????

What next?? the booster, not enough vacuum, have I been looking in the wrong spot and wasting money on new discs etc??

PS I love this hemisphere difference in time and day. I ask the question as I head off to bed and, all your wonderful responses are waiting for me in the morning.

Very much appreciated.

There are a few possibilities: Hub was not cleaned well enough before installing rotors making it wobble, rotors not brake ready and need turning or the front wheel bearings need replacing based on the vibration in the brake pedal described.

Could also be an alignment issue however you should be noticing uneven tire wear and feeling that in the floor. That you had this before replacing the rotors would point to the wheel bearings.

[AriK]

I switched off the engine and let the car coast. I then applied the brakes, much more effort required, of course, but, guess what, not a scrap of noise or vibration.

Boosters should be able to hold vacuum for quite some time after shutdown. To test, allow your car to sit for some time and check if you still have at least one soft stroke of the brake pedal. If not then look for a vacuum leak. Maybe a hose or the booster valve leaks in a way that it creates vibration.

[jandarah]

Hi, more good food for thought.

As I said previously, I have no history of the wheel bearings, so it would be a good idea to order some and new inner seals and do a complete changeover.

In relation to the new discs, the accompanying paperwork did not indicate any need to machine them, only to clean off the anti corrosion coating.

I must admit that I did not really check the cleanliness of the disc to hub join.... I do have some new locating/fixing lugs coming, so that will be a good time to check that.

There is no irregular tyre wear, it is actually very even across both tyres.

OK on the brake booster and holding enough vacuum for one soft brake, after killing the engine, I will give that a go also and check the vacuum lines also for any irregularities/leaks. For some reason, the previous owner has left the vacuum line in two pieces, with a brass joiner.

What explains why the noise/vibration disappeared with no engine/booster running????

Also, where the vacuum hose connects to the plastic fitting on the booster, should that fitting be able to swivel freely around, but still remain locked in the booster?

Thanks again, have a nice day/evening, hope winter is not too savage in your part of the world.

[DieselSpider]

Many times without boost you won't be applying enough pressure to the brakes to cause the rotors to pulse back through the pedal especially if its not from warped/rusty rotors however if the pulsation occurs when the car is not moving there could be a fault in the brake booster making it hammer instead of apply smoothly however this will be the first time I have ever heard of that. Pulsation/vibration not caused by warped/rusty rotors, bad wheel bearings worn tie rod ends or other worn suspension components could be from the ABS Pump or Valve however our cars do not have ABS.

[jandarah]

Hi, since we have corresponded a bit now, not sure if I can call you Diesel or Mr Spider!!

OK on all that, no it doesn't do anything when the car is stationary. I have ordered a bearing kit for each front wheel, so that will be another job out of the way and might assist with this matter. Next, after I sort out this problem, might be the replacement of the shocks. The ones on all four sides are an ordinary shop brand called Pedders. They don't get much of a review. What brand of shocks do you use? Konis are available here, but come with a hefty price, I believe. If I am going to do it, then I want to use top class ones.

Oh, if I can help with getting Isuzu diesel parts, then PM me and we can see what we can do. Not sure of Customs or freight costs to the US from here.

[jandarah]

Hi all,

More to the story. I replaced both front bearing assemblies the other day with SKF product. While the ones that I removed did not look too bad, it was interesting to see what came out. Out of the four bearings, I removed one large SKF, one large NIS, one small NTN and one small Timken...... how interesting, sounds like it was "just put in whatever you can find and fit". Also the grease colour was different in each hub, one red, one more grape coloured. One can only imagine how the previous owner was treated by mechanical workshops????

Anyway, bedded them in on the road yesterday and, with a bit of re-adjusting this morning on one wheel, all seems good and maybe the braking noise is lessened even more .... Yeh....

Knew you would be interested and awaiting the next installment. I did ask if it was normal for the hose fitting on the booster to be able to be swiveled around or should it be tight??

Cheers,

[DieselSpider]

The vacuum hose fitting is just push fit into a rubber grommet on the brake booster. It should have some resistance and should not be loose however you should be able to spin it.

[jandarah]

Thanks.