Brake experts ~ please expose yourself!

[Aln]

Called Alan's recommendation in Woodridge http://www.accuratesuspension.com.au/ & booked in Thursday week....JG.

I don't think you will be disappointed. I remember Ken adjusting torsion bars on an old Valiant (AP6?) many years ago because most others the owner had asked wouldn't touch it. I expect he has seen most things that can happen with car suspension, and the cars he works on are usually very competitive.
Ken and Pauline still both compete ( Datsun 1600 SSS with N/A KA24 Bluebird motor he built himself. 250Hp @ wheels) and both are still at the pointy end at Hillclimb and Motorkhana events.

 

[RINGER]

Does anyone familiar with Light 15 front suspension know if the 2 front torsion bar adjuster screws be fully removed without pulling everything apart?
I've rebuilt both rear adjusters this afternoon & modified slightly so one can adjust very easily, even without 'the' special tools.
Started on the front & in droop position the RHS one screw is only finger tight....oops there could be part of the pulling issue.
Thx JG.

 

[Greenpeace]

I don't think you will be disappointed. I remember Ken adjusting torsion bars on an old Valiant (AP6?) many years ago because most others the owner had asked wouldn't touch it.

All the Aussie Valiants had the same torsion bar front suspension. Biggest issue with wheel alignments was setting the camber, particularly if the car was lowered. The camber adjusters were only accessible over the top of the wheel and the first thing a wheel aligner would do would be to jack the car up under the body to gain access. Trouble was Valiants could take a day or so of driving for the front suspension to settle back properly after being allowed to drop to any great degree. So the accuracy of any camber changes made, were almost impossible to verify there and then, regardless of how much the tech bounced the front end up and down.
The guy I used to use had an aligner that (if you asked) allowed him to remove the front wheels and then bolt stands to the wheel hubs. He would jack the cars up under the lower control arm to fit these plates so as not to disturb the natural ride height. I probably had the only significantly lowered Valiants around my area at the time that didn't regularly scrub their front tyres out.

 

[RINGER]

Can the Light 15 front suspension's 2 front torsion bar adjuster screws be fully removed without pulling everything apart?

Adjuster screws can be removed with some difficulty in about 10 minutes each side, loosening enough so the ball drops out of the cup then twisting to screw right out. This is way better than removing all the setup if that is all y'all want to replace. Below is the tool I made for the front adjusting screws.

.

 

[RINGER]

Has been a gr8 day & after doing a few simple things we are pulling up in a straight line.
1. Pulled each caliper F&R slides apart & lubricated with Bendix Brake lube satchel from Supercheap $1.90 trade, both front were new & had little to no lube.
2. Pulled & inspected all NEW pads - glass sheet figure 8 motion & 80 grit cleaned all up to be new again.
3. I DO NOT RECOMMEND HEAVY BEDDING IN - IT CAN BE COUNTER PRODUCTIVE & GOOD PADS DON'T NEED THIS
4. Removed all F&R torsion bar adjusters, cleaned threads, fitted spacers so nuts were in full view, EZ to turn unloaded & replaced rear adjusting nuts.
5. While doing this jacked up & leveled hull on 4 stands.
6. Wound both back adjusters equally to what felt like was about right [central on thread].
7. Both front adjusters were wound up until contact made then 2 full application turns.
8. Dropped to the ground went for a run. Ride & brakes were better.
9. Came back measuring difference side to side & ride height.
10. Decided to set both front & rear @ 270mm ride height.
11. Jacked each axle, in turn, to adjust to optimum ride height.
12. Ran back adjusters off 3 full turns each side.
13. Front off 1 turn on the L & 3/4 turn on the R.

Went for a run on deserted road & @ 70km/hr this is what I got - prefect straight line FULL stop in a real hurry.

Tomorrow I'll go for another Roller Brake Tester report, post here & will also go to Alan's recommendation Thursday week in Woodridge.
I'm so happy all is coming to work out as it should.
This weekend will re-adjust tranny cable linkages with help from a buddy - my usual Fitter & Turner neighbour is in NZ for a month.
Thanks, especially Gerry, for the help & all who offered recommendations. JG.

 

[RINGER]

AXLE​	STATIC WEIGHT LHS T​	STATIC WEIGHT RHS T​	BRAKE FORCE LHS kN​	BRAKE FORCE RHS kN​	PEAK DECELERATION LHS %G​	PEAK DECELERATION RHS %G​	PEAK DECELERATION BALANCE %​
FRONT​	0.25​	0.30​	1.2​	1.4​	48.9​	47.6​	97​
REAR​	0.25​	0.30​	1.2​	1.2​	48.9​	40.8​	83​
​	​	​	​	​	​	VEHICLE SERVICE BRAKES PEAK DECELERATION​	46.3%G​

 

[pugwash]

has it made a difference in how it feels to drive, corners etc ? being perfectly balanced now .

 

[RINGER]

Is better in all respects but will let y'all know after next Thursday. JG.

 

[The Gonz]

Brake experts ~ please expose yourself!​

 

[jaahn]

Just a comment on torsion bars. With coil springs and leaf springs they are made to a set shape and length so can be just put in place and the car sits more or less at the height designed.
But a torsion bar is only half of the system as it needs the arm to apply the force to the suspension or the arm is the suspension arm. The bar is usually splined due to the forces so can be fitted (each end) in multiple positions. So to get a set height there needs to be a procedure to set them up. Note some have slightly different spline counts on each end to get a vernier adjustment that is easy to make but you do need to know what you should do, or you'll f*ck it up. Screw adjustments are easier after you clean off the rust and dirt and lube them.

However the real challenge is having four wheel torsion bars. As you have an adjustment on each corner it is not simple to get it correct and sitting evenly and with equal weight on each wheel. The factory adjustment is OK but some commonsense and small adjustments probably is called for at home, or 4 weight tables for instant correction. But check the heights too as you go or it will not sit flat.

Note I have not done all these things. Just f*cked up a few to find the pitfalls then researched to correct them.
Jaahn
Good luck Ringer, you look to be on the right path now. That car is just a fun learning event

 

[jaahn]

AXLE​	STATIC WEIGHT LHS T​	STATIC WEIGHT RHS T​	BRAKE FORCE LHS kN​	BRAKE FORCE RHS kN​	PEAK DECELERATION LHS %G​	PEAK DECELERATION RHS %G​	PEAK DECELERATION BALANCE %​
FRONT​	0.25​	0.30​	1.2​	1.4​	48.9​	47.6​	97​
REAR​	0.25​	0.30​	1.2​	1.2​	48.9​	40.8​	83​
​	​	​	​	​	​	VEHICLE SERVICE BRAKES PEAK DECELERATION​	46.3%G​

Hi Ringer looking better and better.
The resolution of the static weight measurements appears to be 0,05T so they could actually be quite a bit closer. The same can be said for the brake force figures, resolution of 0.1. You did good !!
Those hand brake decelerations must be a world record for a Traction. 46.3G would actually be very useful which is more than I could say for the Tractions I have had You just need a ratchet release that can be released easy !
cheers Jaahn

 

[RINGER]

Those hand brake decelerations must be a world record for a Traction. 46.3G would actually be very useful which is more than I could say for the Tractions I have had You just need a ratchet release that can be released easy !
cheers Jaahn

Tractions had the early '30's first real hydraulic type brake system, Lockheed twin bottom anchor very poor brakes in their day & particularly now.
46.3g was the service brakes not hand brake. The park brake is an electric one & I decided it works so well I was not going to let the dyno have a go @ proving same.
I think a little fooling around next Thursday & all will be perfectly balanced.
Currently I am happy to sit in 110km/hr freeway traffic in my Traction & will be doing a couple of hundred km that way next week. 110km/hr is 4000rpm & I'm adding an additional muffler as it sounds a bit like it's on the track.

 

[RINGER]

The new rear muffler added sounds perfect!

Test 1 ~ Nothing done, initial readings & brakes pulling severely left

AXLE​	STATIC WEIGHT LHS T​	STATIC WEIGHT RHS T​	BRAKE FORCE LHS kN​	BRAKE FORCE RHS kN​	PEAK DECELERATION LHS %G​	PEAK DECELERATION RHS %G​	PEAK DECELERATION BALANCE %​
FRONT​	0.30​	0.25​	0.9​	1.0​	30.6​	40.8​	75​
REAR​	0.20​	0.35​	0.8​	1.1​	40.8​	32.0​	78​
​	​	​	​	​	​	VEHICLE SERVICE BRAKES PEAK DECELERATION​	35.2%G​

Test 2 ~ hull supported @ 4 points all equal height/distance from the deck ~ backing off everything so no load, cleaning up threads, Kopr Kote lubing & with all axles/torsion bars unloaded @ full droop, adjusting to where I estimating things should be & similar resistance to turning torsion bar lever was experienced

AXLE​	STATIC WEIGHT LHS T​	STATIC WEIGHT RHS T​	BRAKE FORCE LHS kN​	BRAKE FORCE RHS kN​	PEAK DECELERATION LHS %G​	PEAK DECELERATION RHS %G​	PEAK DECELERATION BALANCE %​
FRONT​	0.30​	0.25​	0.8​	1.1​	27.2​	44.8​	60​
REAR​	0.20​	0.35​	1.0​	1.2​	51.0​	34.9​	68​
​	​	​	​	​	​	VEHICLE SERVICE BRAKES PEAK DECELERATION​	38.0%G​

Test 3 ~ After a good run coming back & adjusting both rear hull floor measurement & both front torsion bar centres to 265mm from flat floor level.

AXLE​	STATIC WEIGHT LHS T​	STATIC WEIGHT RHS T​	BRAKE FORCE LHS kN​	BRAKE FORCE RHS kN​	PEAK DECELERATION LHS %G​	PEAK DECELERATION RHS %G​	PEAK DECELERATION BALANCE %​
FRONT​	0.25​	0.30​	1.2​	1.4​	49.9​	47.6​	97​
REAR​	0.25​	0.30​	1.2​	1.2​	48.9​	40.81​	83​
​	​	​	​	​	​	VEHICLE SERVICE BRAKES PEAK DECELERATION​	46.3%G​

Test 4 ~ With 80kg driver on board, weighed on all 4 wheels & adjusted so all axle weights each side were very close to being equal ~ within 15kg.

Vehicle overall weight with driver ~ 1200kg.
Wheel alignment done ~ toe & caster both adjusted.
Straight line steering is much better, brakes seem much the same but may grab less & better feel.

I need to check into why the rear brakes have gone back so far v/s test 3 [with only adjusting the RHR side tension up to get all wheels on the same axle supposedly balanced.
When checked on a RBT after a 100km motorway drive home on 110km/hr with no heavy braking before the test?

AXLE​	STATIC WEIGHT LHS T​	STATIC WEIGHT RHS T​	BRAKE FORCE LHS kN​	BRAKE FORCE RHS kN​	PEAK DECELERATION LHS %G​	PEAK DECELERATION RHS %G​	PEAK DECELERATION BALANCE %​
FRONT​	0.30​	0.30​	1.4​	1.5​	47.6​	51.0​	93​
REAR​	0.25​	0.30​	0.9​	0.6​	36.7​	20.4​	55​
​	​	​	​	​	​	VEHICLE SERVICE BRAKES PEAK DECELERATION​	39%G​

Any ideas anyone has will be gratefully accepted. Offers please? Thx JG.

 

[JohnW]

Tractions had the early '30's first real hydraulic type brake system, Lockheed twin bottom anchor very poor brakes in their day & particularly now.
46.3g was the service brakes not hand brake. The park brake is an electric one & I decided it works so well I was not going to let the dyno have a go @ proving same.
I think a little fooling around next Thursday & all will be perfectly balanced.
Currently I am happy to sit in 110km/hr freeway traffic in my Traction & will be doing a couple of hundred km that way next week. 110km/hr is 4000rpm & I'm adding an additional muffler as it sounds a bit like it's on the track.

Great thread thanks. I'd hazard a guess that you could drive around the world reliably at 4,000 rpm.

 

[RINGER]

This engine is so clean inside I believe it is near new.
Lots of perceived issues are being sorted one by one.
Really appreciate learning new things about vehicles I'm coming to know but always liked artistically & y'all help with advice adds to my & everyone's knowledge pool. Thanks John & y'all. JG

 

[RINGER]

4 weight tables for instant correction. But check the heights too as you go or it will not sit flat.

That is exactly the setup Ken had hooked up to a central screen, with like an excel spreadsheet layout, with the 4 individual wheel loadings/weights & overall vehicle weight.
Quite sophisticated equipment & when he was finished adjusting rear. all weights showed up as very close to equal & the vehicle looked level. Current readings/measurements are rear both level & front LHS is down about 10mm but I'll check accurately & post measurements when I get home from work today.

 

[RINGER]

I'm imagining with the original Light 15 Citroen Lockheed brakes [very hard to adjust @ any time the same on WW2 Jeeps] they would have been a real mongrel to get pulling up straight @ anytime as the torsion bars being setup spot on seems problematic. Just look @ all those static weight differences on each of these tests just by adjusting the torsion bars slightly.

 

[Greenpeace]

I'm imagining with the original Light 15 Citroen Lockheed brakes [very hard to adjust @ any time the same on WW2 Jeeps] they would have been a real mongrel to get pulling up straight @ anytime as the torsion bars being setup spot on seems problematic.

Just as a point of interest the Harley Servicars with juice rear brakes ('51 to '72) used Jeep brakes on the back wheels. Haven't had any dramas with mine in 16 years other than the master cylinder leaking.
But then it doesn't get used a lot either.

 

[RINGER]

Jeep brakes after WW2 & CJ2's did not have twin adjustable bottom anchors [but sliding anchors] so they were relatively EZ to adjust in comparison.
They are just nowhere near as good as floating self energising type bottom connected shoes anchored @ the top introduced in the 50's & used on most marques through to the introduction of disc brakes.

 

[Greenpeace]

Servicars use M38 ('49 to '52) Jeep rear brakes and they have individual cam adjusters for each shoe.