Restoration Questions.

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Restoration Questions.

Postby Drift_240 on Sat Jun 14, 2008 6:20 am

Hey guys, so I have been working on my frame rails lately and I'm wondering about how to improve on the frame rather then just replace it.

so obviously our cars have poor drainage which is why the frame rusts out at the lower point under the firewall. When replacing how would you go about improving the drainage so it is less likely to cause a problem in the future. If adding drain holes is a good idea, how big should they be? are a couple 1/2 inch holes a good size? Would putting a sponge and a drain hole in the higher part help to avoid rust or just make it worse?


I am also trying to decide the course I want to take with my rear brakes, The front brakes are going to be 300zx brakes and the rear brakes are shot and seized. My car is a 1990, should I replace them with some newer ones or try to rebuild them? Where could I get a rebuild kit?

I will also need a machine shop to redrill my brakes as I dont have a drill press here, does anyone have some suggestions in the west end? How close are tolerances for this, can it be done by clamping the 4x114 rotor over it or should a rotary chuck be used?

I will also soon be in need of some random parts. Off the top of my head I'd like to pick up a less rusty hatch lever (by the drivers seat) and the drivers side headlight motor assy, maybe an SOHC exhaust manifold aswell. Who has this stuff lying around?

thanks
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Re: Restoration Questions.

Postby Nave on Sat Jun 14, 2008 3:50 pm

The problem with the framerails isn't so much the drainage as it is all the overlapping. I have always cut out the whole rail and fabbed new sizes and a bottom. I've done it a couple different ways but in the end I make it so you can still can at the inside of the rail through the floor. Then when it is all welded I paint the whole rail, inside and out and once it is dry I replace the small section of the floor. A hole in the bottom is good for sure, but it isn't like the rail fill with water, there are holes furthe down that a lot of water would drain out of. Like I said, it the overlapping pieces that get moisture/salt/etc trapped in them. When you cut the rail apart you will see what I mean.

If you aren't going to put Z brakes on the back also just get new calipers. I would get some rebuilds from NAPA if you can't find a GOOD used pair (getting harder to find). Don't bother rebuilding them, it's a PITA, not much more for rebuilds, and I don't think you can just get a rebuild kit anyway.

Are you making the rotors 5 bolt when they used to be 4 or are you cross drilling them?

Just ask for parts and I'm sure someone will pipe up.
- 90 Coupe a la SR
- 90 Coupe a la KA
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Re: Restoration Questions.

Postby Drift_240 on Sat Jun 14, 2008 5:33 pm

I need to redrill the 5 lug 300zx brakes to 4 lug
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Re: Restoration Questions.

Postby philip_240sx on Mon Jun 16, 2008 1:42 pm

I've always redrilled mine from 5 to 4 lug by simply bolting a 4 and 5 lug rotor back to back using a 12mm nut & bolt in one of the bolt holes. After carefully lining everything up, I used a 1/2 drill bit, a hand drill, and plenty of cutting oil (WD-40 works) to drill the remaining 3 holes from 4 bolt side. Even if it's slightly off, it doesn't matter as the rotor is centered by the hub not the bolt holes. The 1/2" drill bit is slightly oversize for the wheel studs and compensates for any misalignment.

BTW, the oil helps as I have drilled at least 3 sets of rotors with the same bit and it's not even worn. Just be sure to completely clean the rotors of oil once finished.
- Philip Agnoletto
'08 Rogue SL
Prev Nissan's: '87 Pathfinder SE, '90 240SX, '03 Altima 2.5S
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Re: Restoration Questions.

Postby bartyb on Mon Jun 16, 2008 2:49 pm

As was mentionned, you only need a press drill for your rotors. Like Philip I also put a bolt in both rotors, and I have made a cylinder out of a piece of mild steel the exact diameter of the center bore and put in in them to prevent any movement, as mentionned, it's the center bore that provides the centering. I also double clamp both rotors together and to the drill support plate.

For the frame rails, I use stainless steel sheet metal, that I bend to shape, so basically I make new frame rails, this bending reduces the amount of welding required, and makes the job quicker imo. There are already holes on the lower section of the frame rails, so I wouldn't bother drilling holes in the section that usually rusts out since it's much higher. I guess having access to a machine shop helps.

The rear brakes on our cars have a tendency to seize, I would just get remanufactured ones as Nave mentionned, they go for around 70$ each iirc. And then each year clean,grease them up and you won't have problems. Trying to do it yourself will be a testament to your patience, that is if you actually suceed in poping the piston, if they are seized real good, you won't be able to without damaging the rest,your tool or yourself. You could always go with 300zx rear ones, but with with the drums in the back, it's just more work, and it doesn't sound as you need it, ~80% of the braking is done in the front anyways.
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Re: Restoration Questions.

Postby philip_240sx on Wed Jun 18, 2008 12:35 pm

Those frigg'n 240SX rear calipers are notorious for seizing up. Rebuilds are definitely the way to go if they are pooched. Replace them and make sure you look after them. Disassemble, clean and lube yearly, or every 6 mos if you drive during winter.

Nissan has learned from this mistake on the 240 as nearly all rear wheel disc models now feature seperate drum e-brakes a-la 300ZX. You still need to clean them yearly, but the caliper is much simpler and less prone seizing.
- Philip Agnoletto
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Prev Nissan's: '87 Pathfinder SE, '90 240SX, '03 Altima 2.5S
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