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It's been a while since I posted an update on the restoration! I have been driving the car - I have 488 miles on it. I reset both front and rear floats using the method in the factory workshop manual. To do so, I cut some "3d" finishing nails to the approximate lengths of 14 mm and 15 mm and then finished them to size with a benchtop grinder. The procedure from the factory workshop manual:

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Holding the assembly in its installed orientation (not upside down), I first place the 15 mm nail section in between the flat metal part of the float and the underside of the float chamber cover. I put it in place using needle nose pliers so that it is straight vertically. I pinch it to hold it in place by lightly squeezing the float and the chamber cover together. Note that when held in the installed orientation, the needle in the needle is in "free fall" and is in a fully open position. Then, using a magnifying glass, I inspect the area of the float tab and the tip of the needle. I verify that the tip of the needle is not touching the curved arm (tab) of the float. It does have to be within 1 mm of it however. If not, when you swap to the 14 mm nail section, the tab will still not touch the tip of the needle. I adjust the tabs so that both carburetor floats contact the tip of the needles with the 14 mm section of the nail in place.

Interestingly, after I had set the floats this way, I noticed that with the 15 mm section of the nail in place, I could blow through the fuel inlet tube, and with the 14 mm section of the nail in place, I could not. So, what I found was that from fully open, to seated, the needles have less vertical movement than 1 mm.

While I have been driving the car to break the engine in, I have been looking at air fuel ratios (AFR) using a wideband 02 sensor. I swapped from what I believe to be stock N27 needles to some SM needles. But, I have observed AFRs moving around a bit which is unusual and not expected, and which I think may be due to the engine still breaking in. I started a separate thread that details more about what I was doing and seeing here: https://www.classiczcars.com/forums/topic/69292-choosing-an-su-needle-if-i-have-needle-station-info-and-real-world-afr-can-i-use-that-to-find-the-right-needle/

This weekend I plan to do a leak down test on the engine to confirm break in is complete, change to standard oil (instead of break in oil), and adjust the valves. If the engine is fully broken in, I will do some more AFR testing and determine how to proceed. I may need to modify the SM needles in the cruising and pick up stages by some very light "sanding" - removing material by chucking them up in drill and using 2500 grit sandpaper only in a certain area of each needle.

With the driving I have done, I also noticed a vibration at higher speeds. I started a separate thread for that issue: https://www.classiczcars.com/forums/topic/69334-how-vibration-free-is-your-70-71-240z/#comment-675670

Today, I am going to buy a digital angle gauge so I can check some angles in the driveline. I am hopeful doing this will help me determine the cause and fix that issue.

Edited by inline6



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The odometer clicked over 500 miles on Friday night, so I took the valve cover off yesterday and did both the leak down test and adjusted valves. Here were my leak down percentages:

#1 = nearly 4%
#2 = 2-3% closer to 2
#3 = 4%
#4 = 4%
#5 = 3%
#6 = a little over 1%

For my Iskenderian cam, the valve lash is .006" on the intakes and .008" on the exhaust. I set each so that the feeler gauge was a snug fit while the engine was cold. All of the cam lobe surfaces looked great!

The next time I fire it up and get the oil warm, I'll change the oil.

Today, I removed a portion of the exhaust and the driveshaft and measured the angles of the front engine dampener and the pinion flange on the differential.

IMG_20250420_114825.jpg IMG_20250420_114855.jpg

I believe I will be able to lower the transmission rear crossmember to bring the engine/transmission assembly to the same 87.1 degrees that the pinion flange is at. I will just need to add shims between the transmission crossmember and the car body. Oh! And I just remembered that I should check the angles in the horizontal plane (not just vertical) as well.

Edited by inline6

  • 4 weeks later...

I put the progress dealing with the prop shaft and transmission and differential angles in another forum thread.

While I was repainting the driveshaft, I also painted the front grill. The front grill, rear tail light trim panels and the hub caps all share the same paint. I bought the paint for these near the beginning of my restoration. If I recall correctly, I told the paint supply place the info for the color that is in the How to Restore your Z Car book.

I painted the grill, but the color was too light - it was too grey, at least comparing to my original, not repainted hubcap. I got some crap in it too. So, repainting was necessary. This time, I took a guess, and added 10% of black paint (by weight) to make it darker. I think it came out a bit too dark, but I like it a lot more than what it was.

IMG_20250505_212741.jpg IMG_20250505_212757.jpg IMG_20250505_212705.jpg


I think I will experiment a bit more with it, adding maybe 5% of black and seeing how that looks. Then, I will repaint the tail light trim panels and possibly the hub caps as well.

I installed the front grill today. As you can see, the paint is a little darker than the original, but I am not interested in painting it for a third time, especially since I have a wrist cast for the next six weeks. Interestingly, when in the sunlight, the original paint does appear to be metallic. The metallic particles seem smaller, less noticeable, but they do reflect. This is not easy to capture in a photo (second pic here):

IMG_20250518_120315.jpgIMG_20250518_120225.jpg

Original grill hardware:

IMG_20250518_123906.jpg IMG_20250518_122523.jpg

IMG_20250518_120159.jpg

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Edited by inline6

On 11/14/2023 at 10:40 PM, inline6 said:

IMG_20231112_154648.jpg 

Left rear hook on the front right of the car.  Hook portion should point the other way.  I will need to replace this hook with either the middle of the right one above.

IMG_20231113_171842.jpg

 

Does anyone have fastener specifications (size and grade)?

Thanks,

Keith

Edited by zed2

19 hours ago, zed2 said:

Does anyone have fastener specifications (size and grade)?

Thanks,

Keith

yellow chromate hex head bolts (4 on recess in head) M10 X 1.25 - 25mm under head - fully threaded
yellow chromate split lock washers - M10
yellow chromate flat washers - 22mm od - 10.5mm id

Not comprehensive, but a good start - speadsheet cataloging the hardware on a 240Z:
https://docs.google.com/spreadsheets/d/1Cmnw0F8N7B3VknCzNwGkfN2SGmIHdFJhDjARv3jkxNI/edit?usp=sharing

The above descriptions are found by looking at the "rear bumper". There is copy of the workbook in the resources section of this website as well.

Sorry, I had to edit that significantly!

Edited by inline6

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