The Blasting Saga

1973 Datsun 240Z Resto-Mod

I never posted my progress on the abrassive blasting, and it was an ordeal, so here are some photographs that will give you an idea.

The second batch of glass I bought had some consistency issues. The left is the Black Diamond, the right is the second company, and the middle is what I sifted out of the second.

After aircraft stripping the undercoat.

Long story short, the undercoat soaked up two of my five days. The neutralization process for the aircraft stripper resulted in flash rust, and I ended up sending it to the paint shop. A large portion of the work I had intended to do myself is now happening there.

It’s a bummer but at least we’re still moving forward.

Blast It!

1973 Datsun 240Z Resto-Mod

In a week I will be taking a week off of work to make a major push on getting the car ready to get painted. I had initially planned on having the car stripped professionally, but it’s looking like $4,000 when you factor in transportation and everything else, which is about double what I can swing. So I started snooping around the internet and found that it is possible to do a lot of that work one’s self in the garage / driveway.

The first thing I would need is something to strip the car. There are three major categories of options here: chemical stripping, abrasive blasting, or sanding. I’ll be doing all three. First, I bout a small abrasive blaster. Initially I had planned to use soda because it is gentle and environmentally friendly. The problem with soda, though, is that you have to do a ton of work to get the metal prepared to accept paint or you end up with several thousand dollars worth of labor and pain flaking off in a few months. So I ended up getting this little guy from Eastwood. It’s not the best one, but it isn’t bad and it isn’t expensive. I’ll be putting crushed glass in it, which is what I have found is the choice of several professional blasters whom I had considered hiring out for this job.

Almost Stripped

1973 Datsun 240Z Resto-Mod

The car is now ready to flip! I did a test flip and found out that I don’t have it balanced quite right, and that the rotisserie won’t let me go to a full 90 degrees. I will make some adjustments and see what happens, but even at one notch from fully sideways it’s still WAY easier to get in there and pull parts off.

The next step is to strip the brake and fuel lines, get the last few bits and bobs off, and scrape the underside so I can sandblast on the 17th.

Light in the Front

1973 Datsun 240Z Resto-Mod

The front suspension is off! I had a stumble and it took me longer than I thought because I didn’t want to follow the process outlined in the service manual. The book wants one to remove the entire front end as a unit and then disassemble it. Given that I wanted to keep the car on jack stands until it’s stripped to give the rotisserie a break, I couldn’t get the car high enough off the ground to make the struts clear it when I pulled it out.

So I ended up doing a slow and methodical disassembly of the unit while triple checking it at every step to make sure nothing was going sideways.

After the front hubs, brakes, dust shields, rotors, etc. we’re off I took the tie rod ends and various other bolts off one at a time.

I had to remove the bar that ties the two ends of the rotisserie together in order to get the kick under there to support everything, but eventually all the components were separated and I was able to pull the knuckles out, followed by the struts, and then the cross bar and steering rack last.

Gas Tank Reconditioning

1973 Datsun 240Z Resto-Mod

I learned something this weekend:

After setting up all the chemicals I bout for this gas tank restoration, I have determined that a) the Por-15 reconditioning kit doesn’t work, B) muriatic acid is scary, c) either the water in my neighborhood is too hard or rinsing with water is stupid, and d) you only need three things to do the inside of your tank.

Engine Buildup: Addressing Some Problems with the Mechanical Rocker-Arm Pivot Conversion

1973 Datsun 240Z Resto-Mod

We are doing some research on the inserts today, and tomorrow I’ll call the maker about the insert’s hardness. Maybe it isn’t a poblem because, with the pivot post holding the assembly in the hole, the insert sees mostly compression forces rather than shearing forces.  But it seems a bit “hokey.”

I like the idea of a threaded aluminum sleeve but rather than machining the entire depth of the hole, maybe have it thread onto the pivot and slip into the hole. We could secure the sleeve to the head with green locktight to keep it in place. Still expensive though; I’ll need to look around.

Also, I think it’s interesting that this modification has been around so long and there’s hardly any mention of pluging the oil delivery ports. Seems to me that there will be some oil seepage beneath the pivot post if the port isn’t plugged.

Engine Buildup: More on the Rod Problem

1973 Datsun 240Z Resto-Mod

I didn’t ask the machinist what the rods were off by and since I couldn’t be as accurate as he with the tools I had, I had to go with the re-fit. Even if I had him leave the big ends together so I could measure them, I don’t have a rod vise to hold the big end while removing the nuts. I probably could have used a vise without serated jaws, but there’s no sense taking a chance on twisting the rod. The important thing is that when it all went together the plati-gauge crush was good and the crank spun freely.

Engine Buildup: An Observation about Plasti-gauge

1973 Datsun 240Z Resto-Mod

I did the plasti-gauge crush check on each rod and finished each cylinder completely before moving to the next. The crush test on #5 was a little wide but appeared to be within limits when compared to the scale on the plasti-gauge wrapper, so I went forward with assembly. Number six was not as tight so I completely didn’t expect a problem. You understand correctly that the crank bound up as I increased torque on each cap.