Garage with with NCT type rolling road for brake balance?

jk536

I failed the nct during he week due to a rear brake inbalance. The car has drums on the back and I had adjusted them as best at I could to balance the 2 sides but still fell short.
Do any of ye know any garages that have a similar set up to the nct centers where i can get the rear brake imbalance measured while adjusting to eliminate any guess work?
Im based around Maynooth, Cheers.

corktina

Tip I got at the CVRT centre was to swap the drums over. 50% chance this would make the imbalance worse of course, but worth a shot

DublinDilbert

There has to be some out there but never found one myself.

I have an incline in a hill out in the lane and used to drive up the hill and roll back down. When you apply the hand brake if both sides are pulling evenly both sides will go down at the same time. If one side is pulling more the other side will kick up. Test it with your current adjustment which you know is off balance, You'll see what I mean.

visual

Most rear drums have auto adjusters to take up wear in shoes.

If you have imbalance it may need more than shoes.

Did you check if the drums where worn or if their is contamination from oil.

Some rear brake kits come with new springs and locking pins or washers.

Is the imbalance on rear brake or hand brake or both ?

jk536

Thanks for the replies.
Its an 89 mini that I have restored and have only done about 150 miles, so it has new shoes,no contamination and drums are in good nick. It has the old fashioned square nut at back of the hub to adjust the shoes manually.
It has an in balance of around 40% if i recall correctly in both the rear brake (foot brake) and the handbrake.

I assume that no independent mechanic would have that sort of kit but would the likes of the chains like Atlas or Quickfit?

Stoolbend

To be fair anywhere that had one would probably charge as much as the NCT retest anyway.

visual

With hand brake off should be able to spind wheel freely. Adjust nut until it starts to catch wheel then back off 1/4 turn repeat for other side.

If you have a torque wrench you can pull hand brake up a little so its just holding wheel and see what forces it takes to turn wheel.

Best to be doing these tests with rear of car on axle stands and both wheels off the ground.

Because imbalance is in both hand brake and rear brake its narrows it down to shoes drums and moving parts within drum.

If you find issue in hand brake it should solve rear foot brake too

CiniO

Find some soft surface - gravel or sand.
And driving very slowly gradually apply the brakes until both rear wheels lock (if you have ABS turn it off by taking fuse off).
You will see by marks which side locks first. If they both lock at the same time, then your imbalance is perfect.

However NCT equipment might not be perfectly adjusted - that's the other issue.

jk536

visual wrote: »

With hand brake off should be able to spind wheel freely. Adjust nut until it starts to catch wheel then back off 1/4 turn repeat for other side.

Thats exactly what I did but it appears to be off still.

They are both good ideas with the torque wrench and sandy surface. I think I might give both of these a go, surely if i adjust the imbalance with both techniques it cant be a million miles away.
cheers for the help