Restoration of BringaTrailer 240z - HLS30-35883

[Captain Obvious]

So in the rebuild kit they included new O-rings to seal the two halves of the caliper halves together? That's really nice, but a little weird since Nissan recommends never splitting them apart. Old fading brain cells tell me they didn't do that in distant past.

Maybe I was just buying the wrong brand kit, but I don't remember getting those little O-rings as part of the rebuild kits.

[Captain Obvious]

Oh, and I have these NOS. How OEM do you want this thing to be? 

Edited August 20, 2022 by Captain Obvious

[inline6]

11 hours ago, Captain Obvious said:

So in the rebuild kit they included new O-rings to seal the two halves of the caliper halves together? That's really nice, but a little weird since Nissan recommends never splitting them apart. Old fading brain cells tell me they didn't do that in distant past.

Maybe I was just buying the wrong brand kit, but I don't remember getting those little O-rings as part of the rebuild kits.

As you point out, the factory shop manual says not to remove the bridge bolts.  See a thread I started in the brakes section for a pic of the crud I found in my caliper when I took it apart.  O-rings to seal the bridge connection were not available as replacement parts from Nissan that I can tell.  Some aftermarket caliper rebuild kits do include them.  Some do not.  If you don't take them apart after this many years, you are taking chances.  In addition to the rust and crud inside the passageways, you are relying on 50 year old o-rings to hold their seal.  A leaky caliper makes for a very bad mess - eating paint wherever brake fluid gets.  I messed up a new Panasport wheel years ago because of a bridge seal that failed.

NOS parts are always cool.  But, I don't need them because I had my caliper to strut hard lines re-plated.  They need a bit of tweaking which I will do when I install them.  I sent the platers a brake master cylinder to brake compensator hard line that was like your NOS lines, with that green coating on it.  It came back essentially the same.  So, whatever that coating is, it won't accept zinc. 

Do you have any other NOS items that you won't be using?

 

 

Edited August 14, 2022 by inline6

[Captain Obvious]

13 hours ago, inline6 said:

Do you have any other NOS items that you won't be using?

Not much. Shift knob, front caliper hard lines, timing chain guide. I think that's it.

[inline6]

On 8/14/2022 at 10:44 AM, Captain Obvious said:

Not much. Shift knob, front caliper hard lines, timing chain guide. I think that's it.

Dang.  Bought a new shift knob a while back (has a slight imperfection, but I spent a lot for it - so no interest in spending a lot for another).  Keep hoping I can find someone with NOS Jute.  Not likely, though.

[inline6]

This past weekend, I finally felt it was appropriate to do some wet sanding.  Up to this point, I have done all body work sanding dry, with grits of sandpaper including 80, 120, 180, 240 and 320.  Mostly, I have used 80 grit and then 120 grit on body filler.  And mostly, I have been using 180 grit for everything else.  I have been using 240 grit and 320 grit on fender lips and other areas which require more precision, such as where the forward edge of the body belt line terminates on the front fender.  Truthfully, I have likely been too conservative in that regard.  I have learned a lot about doing body work, as I knew I would.  I just wish I could have learned faster.  Anyway, it was exciting to do some wet sanding.

For wet sanding, I am going over the whole car with 240 grit first.  As I go, I am seeing small areas which will need a bit more primer filler.  However, I am seeing the end of bodywork on this car coming... finally.

I am trying to make sure my belt line is consistent and sharp.  I don't believe I will keep it this sharp when it is to be sprayed with color, but I think it is a lot easier to round off a consistent, sharp line to achieve a consistent finished shape than to attempt to round off a line that is not entirely consistent, if that makes sense.

Right side front fender (pics 1,2,3: front to back, back to front, back portion of fender close up of beltline):
    

 

(pics 4,5, and 6: middle portion of fender close up of beltline, front portion of fender close up of beltline, close up of termination of beltline 

    

 

At the termination point above the wheel well opening, the belt line dips downward a touch.  That should be easy to fix (to be made straight instead of dipping down) by wet sanding the area that still has guide coat on it.  I just need to be careful there.

Edited August 16, 2022 by inline6

[inline6]

I've mentioned this a couple of times before, but I think it is worth repeating for anyone who may do bodywork on their car in the future: panels bolted onto the car change shape, so if you do your bodywork before the panel is bolted down, you will be doing it again after. 

While my car is on the rotisserie, I can't finish the top side of the fenders.  The problem is this: I can't bolt the hood on and finalize the position of the fender where it bolts in several locations along the top, inside edge.  The front rotisserie mounts interfere with the hood hinges, so I can't bolt them into place.  

I forgot about this and "went to town" sanding the top side of my left fender, breaking through the primer filler to body filler as you can see here:

 

And here is where I again emphasize that panels move - that "high spot" I was sanding down is centered above these "support pads" that are underneath the fender surface - the spot is just above the two in the right side of the picture:

 

These closed cell rubber pads contact the fender and apply force to the unsupported part of the panel.  And, depending on that inner edge of the fender's final location, the force could be higher, or it could be lower, causing a difference in the final shape of the fender.  I hope I haven't removed too much of the filler there!  But I won't find out until I can put the hood on and adjust final fitment on the inside edge of the fender. 

This next picture shows the side of the fender a while back when I first bolted the fender on (please ignore the poorly applied guide coat - the can was about empty):  

Same deal: the rubber weather strip on the inner fender support contacts the fender and applies a force to that unsupported area of the fender. In the picture, you can see the guide coat has been sanded away where that rubber is contacting the inside of the fender panel.  It changed the fender shape considerably!  At least I have already reworked this area extensively and have the bodywork for the side of the fender behind me.

Bodywork - will it ever end?

Edited August 30, 2022 by inline6

[inline6]

Realizing that a key next step in the body work for this car was to determine the final fitment of the top, inside edges of the fenders, I proceeded with mounting the hood over the weekend.  In order to do that, I had to first modify the angle brackets connecting the car at the bumper bolt locations to the rotisserie.  I had to cut a small section from them to get freedom of movement for the mounted hood hinges.  With that out of the way, I proceeded to struggle mightily with aligning the hinges and getting the hood to "sit down" all the way.  I didn't take pictures of them, but it is important to note that the "hood - bumpers" (reference A in the drawing), don't just align the hood laterally in the engine bay opening.  They are POSITIVE stops for the hood depth - caps added for emphasis!  I put them on before final adjustment of the height of the fender inner edges, and they were keeping the hood from shutting enough!  Suffice to say... you must leave those off when aligning the hood and fenders, and add them later (as Nissan did after the car was painted at the factory).

 

Hood hinge and hood bolt for documentation purposes:

  

 

On to details about the chore of aligning the fenders with the hood.  After adjusting the hood and fenders as well as possible within their "ranges", the left fender was sitting up higher than the right, a little more in the back (note the inside surface of the fender inner flange can be seen from this angle in the first pic, and less so toward the front of the car in the second pic.

  

 

Well, I couldn't push the inner edge of the left side fender down any further, as it was at the full range of adjustment using the bolt hole openings on the fender inner edge.  That was odd, because I wasn't having the issue with the right side fender.  So, I began to compare the two:

Left side vs. right side - in that order: 

      

 

It is a little hard to see, but perhaps you can make out that the left side fender has about 1 and an 1/8" from the 2 on the tape to the top surface, while the right side fender has about 1 and a 1/32" from the same 2 on the tape.  To get the driver side fender inner edge to align with the hood surface properly, I had to open up the slots in the fender.  I did this by using a die grinder and protecting the opening with a flat steel plate:

 

After a few rounds of this on the fender bolt holes, I was able to push the fender down enough to align with the hood properly.  I then tightened those inner fender edge bolts for the last time and locked in the fender top surface position.  Of course, I then had to "touch up the body work on the fender top surfaces on both sides.  I keep learning my own lessons over and over again: 'don't do body filler work on these panels until they are in final position'.

Tonight I scuff sanded the inner surface of the hood to ready it for primer filler.  The tops of the fenders, and inspection flaps are also ready for primer filler.  With any luck, those will be final coats of primer on those areas - more panels are reaching the point where I can switch to wet sanding with 240 grit.  After that, I should be able to progress to 400 and then 600 to finish out the sanding process.    

 

Edited August 30, 2022 by inline6

[inline6]

I sanded most of the car with 600 grit today.  I have been working most weekends on the body since my last post.  A few areas look to have "moved" to me.  Not the areas shot in this video, but a few other spots.  Perhaps some shrinkage has occurred over the last couple of months.  Body work is difficult and time consuming.
 

 

[Patcon]

That's possible. Most of these products cure for 30 days or more. I always wondered why high ends shops take so long to do cars and they seemed to sit for a long time between fits of work. Maybe that's why, they want all that shrinkage to set in before they continue work?

[inline6]

On 10/7/2022 at 7:49 PM, Patcon said:

That's possible. Most of these products cure for 30 days or more. I always wondered why high ends shops take so long to do cars and they seemed to sit for a long time between fits of work. Maybe that's why, they want all that shrinkage to set in before they continue work?

I was hoping the time between weekends for primer to dry was sufficient, but I can't explain the reappearance of very slight low areas on the right door and flat vertical area of the right fender unless the previous layers shrank.  Most of the bodywork is a year plus old, but unfortunately, I am in a situation where many primer coats are being used in a few areas to build up low areas. 

I used very fine body filler in those areas to attempt to raise them up, and that helped.  But, inevitably, when sanding the body filler, where the filler edge meets the primer, there is a slight transition which I find easiest to address with coats of primer.  

For my 510 that I will do as my next restoration project, I will be doing things very differently, so that not so much primer is needed.  Speaking of which, I bought another gallon Friday.  It went from low $400 last time to $516 this time, with tax.  

[inline6]

With what I believe (hopefully) is the last of the primer coats on the exterior of the car, I have switched to the bottom surface.  There are areas of the floor which had impacts.  These were straightened and the existing undercoat has been sanded down and feather edged.  These photos show basic progress in that regard:

    

 

My plan is to keep most of the original undercoating on the car.  It is in great condition in most places.  Where it is not, I will be attempting to spray Raptor Liner (primer on bare metal areas first).  I've watched a lot of videos on Youtube of people who have experimented with different ratios of hardener, thinner, spray pressure, and spray technique.  In almost of all them, the texture is not like what you see here on the car.  But, I have ideas of how I may be able to get something close.

In addition to continuing to prep the underside today, I hope to have time to experiment a bit.  I am intrigued by one technique I saw where the person used less hardener than is called for and a Harbor freight HVLP gun with the tip drilled out to 2 mm.  He claimed that less hardener allowed the coating to flow out more before drying, and the video seemed to confirm that.  

The Z is small, so the Raptor kit I bought should be much more than I need, allowing for plenty of material for experimentation. 

At the factory, they used a kind of tape to cover bolt holes to keep the coating from getting to threads.  I took some existing tape off where he handbrake part bolts to teh underside of the tunnel (third pic):

    

 

Preparing the underside for a coating of Raptor Liner to repair areas where the factory coating is gone) and give the entire floor a somewhat consistent finish is a lot of work.  I am using small wire brushes to remove the accumulation of dirt cemented in place with oil.  Then I follow with a degreaser/thinner.  Then I follow with more wire brushing and a red Scotch Brite pad.  It is tough to get into all the corners, but I will get them eventually.  Seam sealer will be used on some seams like the overlap of the lower, rear panel to the quarter panel (third pic).