Replace rear disc rotor backing plates

[PeeBee]

I have my '97 GQ booked in for its engineering assessment after a motor transplant. Both of the rear stone shields have broken off and I was told these are required as part of the intergrated assessment. I need a simple straight forward instruction set on how to install new ones please.

I have the brand new nissan backing plates. Seems they are held in place by phillips head screws and I need to remove the disc and caliper. Its far too lomg ago when I last did this.

Appreciate any help pls as i am very time poor and don't have the time to think it out.

Thanks guys, looking forward to hearing from someone soon.
Phil

[dom14]

Hi Phil,

This is not a task that needs much thinking. I'm guessing you bought the backing plates with the correct screws. They are short, fine pitched phillips screws. Use antisieze compound or graphite powder with the screws if you intend to take the backing plates off in the future. Screws get "welded" to the hole over time due to heat and rust and can get pretty hard to undo.
You simply

1)Undo 17mm or 19mm head bolts(2) that holds the caliper and carefully take off the caliper without dropping the brake pads, while
the brake pads still stay attached to the caliper(so it's easy to put it back without having muck around with pads to properly install them. You might need to insert a flat screwdriver between the rotor edge and caliper & lever a bit to slide out the caliper. Just make sure the caliper is NOT hanging from the brake hose(in rare occasions that can cause weak old brake hoses to crack). Hang if free with a piece of wire attached to the chassis somewhere.
2)Take the brake rotor out
3)Fit the backing plate and replay all the above in reverse.
4)Aligning the caliper with bolt holes & getting the bolts in can be bit of a pain sometime, but not that hard.
5)Overall, it's lot easier than replacing brake pads, 'cos you don't need to do much thinking and to be careful, 'cos replacing brake pads need the brake cylinder pushed in with a clamp, carefully, while making sure brake oil doesn't overflow from the master cylinder reservoir.

If you're still unsure, PM me.

Cheers
Dom

[dom14]

Just re-reading your post above, I've been wondering, 'cos you said the original backing plates were "broken off".
By that, did you mean, you've been having hard time getting old backing plate bolts to loosen up, 'cos they have never been undone??!!

[PeeBee]

Just re-reading your post above, I've been wondering, 'cos you said the original backing plates were "broken off".
By that, did you mean, you've been having hard time getting old backing plate bolts to loosen up, 'cos they have never been undone??!!

DOM, thanks for the response. Yes the thin backing plates broke off over time or cracked to the point they were rattling like crazy so I twisted them off. The philips head screws have never been undone. Your description is clear and started me thinking about this again and it became clearer. I have been in touch with the automotive engineer and he couldn't care less if they are on or not, so they will stay off for now and if I get a chance might reinstall them. From memory they caught mud and stones etc.

How did you get on with that alternator project you were working on?

[dom14]

DOM, thanks for the response. Yes the thin backing plates broke off over time or cracked to the point they were rattling like crazy so I twisted them off. The philips head screws have never been undone. Your description is clear and started me thinking about this again and it became clearer. I have been in touch with the automotive engineer and he couldn't care less if they are on or not, so they will stay off for now and if I get a chance might reinstall them. From memory they caught mud and stones etc.

How did you get on with that alternator project you were working on?

I got busy with the other stuff on the vehicle mate. I will go ahead with the alternator project(generator project) soon, but not sure when as I'm bit flat out atm trying to finish off few things on the vehicle.
Yeah, you're right. Most guys take the backing plates off, 'cos when you go off road, crud get trapped in between and cause all kinda problems. I've never pictured backing plates as an RWC issue. I reckon it's roadworthy to NOT have them.
BTW, the trick to get the stuck backing plate bolts out is to place the correct phillips screwdriver on the bolt & give it few hard hits with a hammer to break off the friction/"rust weld" between the bolt and hole. Works like a treat.

[PeeBee]

I got busy with the other stuff on the vehicle mate. I will go ahead with the alternator project(generator project) soon, but not sure when as I'm bit flat out atm trying to finish off few things on the vehicle.
Yeah, you're right. Most guys take the backing plates off, 'cos when you go off road, crud get trapped in between and cause all kinda problems. I've never pictured backing plates as an RWC issue. I reckon it's roadworthy to NOT have them.
BTW, the trick to get the stuck backing plate bolts out is to place the correct phillips screwdriver on the bolt & give it few hard hits with a hammer to break off the friction/"rust weld" between the bolt and hole. Works like a treat.

Thanks Dom, will do.

[dom14]

Thanks Dom, will do.

Hey Phil,
Howz the new engine going?!
I bet it's ready to fly?

[PeeBee]

Hey Phil,
Howz the new engine going?!
I bet it's ready to fly?

DOM, got it back the day before cup day. It had some wiring issues that were not there when it left so I had to spend some time sorting that out. The vehicle is now stripped down for the VASS engineering inspection on Monday. From there its over to Vicroads and then I will be happy to drive it. Its very different to the 2.8! Loads of torque, quicker but no drag car, feels 'raw' in some regards. Currently sorting out the hydraulic pump mount for the front winch. Next is finding somewhere to mount the difflock compressor - there is not a lot of room under the bonnet now either. Anyway another chapter begins i guess and I get a fresh start to try and restrict the amount of crap I bolt or and carry.

[dom14]

Yeah, bigger engines means less room under bonnet, that's the compromise.

Is it NA or turbo?

[PeeBee]

Yeah, bigger engines means less room under bonnet, that's the compromise.

Is it NA or turbo?

N/A. BD didn't want to recommend the turbo due to heat issues. Its an interesting setup as the engine is a turbo spec motor, simply has the turbo removed.If I find the power lacking in the future I will bolt on a supercharger. Right now though I just want it to get the engineering plate and registered with Vicroads so there are no registration or insurance issues. We discussed my application and since I don't tow a camper the turbo was deemed unnecessary. I will see as time goes by.