BJ8 plus 55mph Front end shaking

[Legal Bill]

The vendors (SC parts) says the drums are balanced.

Call Hendrix Wire Wheels. This is what Allen does. He will ask you a lot of questions to isolate the problem and he will know how well those drums are balanced from the supplier.

 

[dougie]

10-4 on the slotted balanced rear brake drums HealeyRick. A pair of these definitely reduced shake on my BJ-7 while improving brake feel and some effectiveness. The process required years to isolate and sort out. GONZO

Ditto .... I had a scuttle shake at 55-60mph for years. Replaced the rear drums with DWR balanced slotted drum about 10 years ago and solved the problem. Fredrick runs smooth now and loves to run with bon jovi.....

 

[thibault]

I have bought two balanced drums from Denis Welch (BRK220VB), to be continued...

 

[pkmh]

Hello all,

I just had my 1st rear set of brake drums balanced from a local guy I know and as a result, driving my BJ8 has significantly improved, say 95%+. Yes, I "STILL" have this tiny little gyration and a low with a repetitive rumbling sound emanating from somewhere, maybe rear or even front, when traveling around 55-60 mph. But again, very slight sensation.

I have a second set of newer brake drums I also dropped off for balancing. I will compare when the 2nd set is balanced and placed back on the car.

I am noting this here because it will be interesting for me and hopefully, for all of us, to learn that just maybe one balanced set may differ from another. I also must note I did attempt to balance my first set using a static balancer, by grinding away the inner flange as best as possible. The balancing pro I went to assured me I did no damage when he needed to drill holes on one end of each drum and welded metal rods near the opposite end of the drums.

Moving forward and not to muddy this thread any, but, if I find that after the 2nd balanced set still achieves the same low rumbling and slight gyrating sensation, and maybe (as one member suggested doing) to swap out the drums at opposite sides (and further even "flipping the drums" after that), then I have to possibly assume, in my case anyway, there may be a transaxle or bearing issue that's needed to be addressed. For the moment, I will dismiss rust, scuttle shake as being any cause only because evidence is leading to a low rumbling sound issue as well as a slight gyration issue.

Any further thoughts on this sound/gyration combination serving as a possible clue to us??

Paul

 

[Michael Oritt]

Dougie--

Nice drive--where is that?

 

[gonzo]

Paul, now that the BJ 8 is driving more smoothly at speed, perhaps another mechanical issue has become more pronounce. The rumbling you described could be attributed to an out of round brake drum / disk, dragging brake pad / shoe or (front) wheel bearing. Do a quick temperature check of the rear drums after a reasonable slow and go drive - no panic stops etc. If the drum(s) baking hot or binding up, something's wrong. Good luck, GONZO

 

[pkmh]

Thank you Gonzo for your advice above.

It just so happens when I drove my car on the highway the first time after reinstalling my balanced drums the other day, I did pull over into a rest stop to perform a simple check of touching my rear drums to determine what temperature both were at. But at that time, I was more concerned to see if I adjusted the brake shoes equally on both sides prior to putting the drums back on. A long while back, I once discovered one side was a little hotter than the other and therefore, I made the necessary adjustments to my drums. But please read on...

Today, in following your advice more closely, I decided to take the Healey on the highway again, maintaining a steady speed of 55-60 mph for a couple of miles, the speed range sufficient to cause that rumbling and slight gyration to steadily occur. Then, I gradually pulled over and stopped into a rest area to observe what's going on with all "four" brakes, not just the rear drums.

My observation was, with both front disc rotors, I was barely able to keep my finger touching the disc rotors. Both were equally high in temperature (not flaming hot, of course, but assuming operating normal due to friction) . With the rear brake drums, both were equally cool to the touch.

Normal?

Assuming for the moment the front discs are functioning normal and not so for the rear drums, then lets assume an adjustment is needed for the rear brake shoes only, and nothing else. I know that to adjust the rear brake shoes, one would adjust the tappet adjusters in order to expand the wedge adjusters, enough until one can hear the drum just slightly touching the shoes after manually rotating by hand. Is this standard and correct? If so, then I have a kicker issue, maybe. I noticed when I rotated the drums, I felt a slight snag occurring at one point only along a 360 degree manual rotation. This is occurring on both sides. Why this slight snag of the drum rubbing against the shoes? And any other thoughts or opinions as to the cause of this slight ongoing rumbling and gyration?

I am still waiting for my 2nd set of drums to be balanced and make a further study/comparison. But as I remembered, that slight snag also occurred when I installed them new from the manufacturer. Still, it will be interesting to learn the results of that. I will post my results when the 2nd set are balanced and installed.

Thanks for any input on this subject.

Paul
PS - In any event, the car rides better than it ever did.

 

[Dandare]

...I was more concerned to see if I adjusted the brake shoes equally on both sides prior to putting the drums back on.

Paul, I don't know if I'm misreading this but should you not be adjusting the brakes after you have re-fitted the drums?

I would think that if you have been able to replace the drums and then not susequently adjusted then you would be under adjusted... hence the cold drums.

Danny

 

[gonzo]

Paul, expect front brakes to get hotter than rears since they do most of the work. Another possible source of rumbling, gyration and steering pull are tires, bad ones, particularly those with separated belts (radial tire). Just a thought. GONZO

 

[British_Recovery]

Next time you have the drums off the rear, take a picture and post it. Something may be revealed.
Bob

 

[pkmh]

Dandare,

I appreciate your question for I wondered when drum to brake shoe adjustments should be made. I noticed that after placing the drums on, I can make the adjustment of turning the tappets till I can really no longer turn them. If this is the preferred way, please let me know. I've done the adjustment both ways, the second being placing the drums on after turning the tappets till the point I can no longer slide the drums on. Which method is the best?

Gonzo,

Thank you for that response. Possible cause could be the tires. If I raise the rear and free spin the tires, would that be enough evidence to see if they're out of symmetry? I do have now installed on all sides, new 72 spoke wheels, new hubs and of course, the new tires. Still waiting for the 2nd balanced drums to be done. Should be interesting to see the behavioral results. To be continued there.

Bob, Please give me a clue what I should be photographing the next time I take off the drums. Brake shoes, inside diameter of drums, that sort of thing. Thanks for that suggestion.

Much appreciated all!

Paul

 

[gonzo]

You could try checking your new wheels and tires for run-out using your described method, but knowing they're new should suffice. Just check the tire's production date code on sidewall to be sure.

I believe Bob is asking for a Drum Off pic of the brake shoe assembly to confirm if shoes are positioned correctly - there's one leading and one (trailing) shoe. Drums are adjusted as you described, but back off the adjuster tappet 1 or 2 clicks so they free spin with little drag.

 

[pdplot]

I have found rumbling or growling noise to be a front wheel bearing. Changes when you turn the wheel. Check it out.

 

[BJ8Healeys]

For an interesting article on what one might do if balancing brake drums/wheels does not provide a solution go here: https://www.britishcarweek.org/scuttle.html

When I had my engine out for rebuild in 1999, I did this modification. I welded the sheet metal around the transmission opening in the firewall in a continuous bead, to replace the intermittent welds, and built the reinforcing structure from 3/4" angle iron. I have had NO scuttle shake since. Of course, I've also had my wheels and tires trued and balanced and the rear drums balanced by Allen Hendrix.

 

[HealeyRick]

When I had my engine out for rebuild in 1999, I did this modification. I welded the sheet metal around the transmission opening in the firewall in a continuous bead, to replace the intermittent welds, and built the reinforcing structure from 3/4" angle iron. I have had NO scuttle shake since. Of course, I've also had my wheels and tires trued and balanced and the rear drums balanced by Allen Hendrix.

I did exactly the same, right down to the full treatment by Hendrix, and have no scuttle shake. I believe this is called the shotgun approach to fixing scuttle shake. Somehow we fixed it, but we don't know what did it.

 

[dougie]

Dougie--

Nice drive--where is that?

Michael -

This is one of my favorite "local" drives of all time (45 minutes from Portland) It's part of the old Columbia River Hwy, I ran it back from The Dallas to Mosier. https://traveloregon.com/places-to-go/cities/mosier/ If you make it out to the PNW, the Columbia River Gorge is a must. Our SOVREN race club holds a hill climb at the "mock-up" experimental road Sam Hill built (ya that Sam Hill, https://en.wikipedia.org/wiki/Samuel_Hill) prior building the to the Columbia Gorge Hwy.
https://sovrenracing.org/maryhill-hill-climb/

Here's a pal in this Cortina

Fall colors are the best, think I'll take a run this weekend as it's going to be 75 degrees on Sunday.

 

[British_Recovery]

As gonzo said, to show the orientation of the brake linings, since they will go on incorrectly without it being obvious.

 

[pkmh]

OK, Gonzo, I feel my tires are good. Cannot recall the manufacture date off hand but when I purchased them, the manufacturer date codes were all the same and within a few months that they were made. They were made on the same week and year and I believe that is as accurate as I'm going to get.

pdplot, I will have to go back and recheck my work to the front end bearings I did a year ago. I did have one scored bearing I did replace. I will follow your suggestion but will wait a bit till my 2nd drum set is completely balanced and back on for comparison. I have to wait till they are ready.

And I will take pictures British_Recovery as suggested earlier in this post regarding the brake shoes and will post.

All to be continued. Sorry for the delays! (I need to retire!)

 

[thibault]

Cool stuff at home

 

[thibault]

I mounted my new drums (DWR) and put the car onto jack stand (without wheels) , I turned on the engine and I noticed tremors, so I'll check the drive shaft. To ne continued...