VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Restoring my '38 Master Deluxe

Thanks, guys for the compliments.

Now I understand why shops charge a lot of money to restore old cars. Even though I hurt my back and scrape knuckles often while doing it, the feeling I get from accomplishing something is priceless.

You mentioned that you will check the backlash in the rearend. What will you do if it isn't what you expect?

The backlash is adusted by bring the ring gear closer to or farther from the pinion gear. This is done by turning the adjusting nuts - one on each side of the side carrier bearings.....round thing with round holes and a lock to prevent turning in service. When adjusted to the proper spec. there wikk be just a "click" between the two gears. A dial indicator is used.

I spent about an hour adjusting the backlash using a dial indicator until it was between the min & max noted in the shop manual.

Since it was my first time, I checked & rechecked with the dial in a couple different places. Probably overkill, yes, but I need to be 100% sure.

On adjusting the rear end, I have been there and done that several times and it is time consuming.

My question was actually exploring whether adjusting the backlash on a rearend that has been in service successfully for many years is desireable. I would think that the backlash will increase with wear. I am wondering whether adjusting the backlash will then position the gears outside of the established wear pattern. I have seen instructions for taking apart a rearend to mark the position of the adjuster nuts before taking it apart.

I had no choice but to adjust the backlash, as I replaced all 6 bearings in the axle.

The manual makes it seem a lot harder than it actually is though.....

As long as the rear end either does not make an excessive noise or make a clunk when shifting between forward and back, it should be okay.

If you want to check it that is and not too time consuming. Drain the lube, remove the cover and manually rotate the ring gear back and forth. If it only moves a little bit and makes a light click it should be okay. Of course checking with a dial indicator is best. If my memory is on then the back lash should be 0.006"-0.010". You can visually check the wear pattern. Use white grease, bluing or other indicating grease to verify the contact is in the center of ring and pinion gears.

If you start with new gears or bearings then the process can take a lot more time. The big time taker is making sure you have the correct shims to locate the pinion gear. That can mean taking the rear end apart more than once to change the shims. Not a fun job.

I agree with the above.....better to let what is working go untouched. The gear teeth are worn in to the original adjustment.

"I am wondering whether adjusting the backlash will then position the gears outside of the established wear pattern."

old 216,

When I converted my '36 PU from 4.11 to 3.55 gears I used a '37 Chevy car axle and '51 car gears to do the job. In researching how to do the job on various forums I learned exactly what you suspect, that a wear pattern is established on used gears.

What I learned is that the tooth contact pattern has to be checked before any disassembly and that pattern must be reestablished after any adjustment of backlash or other work.

The '37-'54 rear end is very simple and easy to service because the position of the pinion gear is adjusted by varying the shim thickness rather than compressing a "crush sleeve". Those crush sleeves require very high torque on the pinion nut to begin to "crush".

You don't have to be intimidated by that rear end. There are some photos and text in this that I wrote for the 1936 Chevy Owners forum but was also dicsovered by someone else and posted on this forum:

https://vccachat.org/ubbthreads.php/topics/334876/1936_Chevy_3.55_rear_gear_conv

Have fun!

Ray W

Finally got the master cylinder rebuilt, finished putting new lines in, cleaned up & put parking brake linkage back together, checked transmission operation while up on blocks before lowering & taking it out of the garage.

Needs a new muffler, but patched it and put back in temporarily so I don't ruffle the neighbor's feathers.

Now I can (finally) start on the body & interior.

Had a friend join me to take the '38 out for a test ride to be sure there weren't any questionable mechanical sounds, as I was the one who rebuilt the transaxle. Used a GoPro knockoff camera with a magnetic base. Interesting point of view if you want to see knee action shocks in action.

When I started it up, it backfired through the carb, hasn't done it until that day...

Chevrolet had comercials like that show the knee-action at work....very intresting.
I know you didn't ask this question but anything behide the grill that can be seen by "looking through the bars" is painted semi-gloss black to make it less visable.

Right, the bottom area is supposed to be black..I got carried away while practicing with the HVLP sprayer...still have to do some sheetmetal repairs in that area.

Here's another video of the knee action up close, camera is cheap so it doesn't pick up a lot of light, but towards the end you can see it. 4 minutes long. Will have to pick a sunny day and put the camera in another location.

Didn't feel like fixing the dent on the air filter. Grabbed one of the spares I had and cleaned it up & painted.

It's amazing how a sticker can add a lot of character to a part.

p.s. I don't think "oftener" is actually a word....

Curious...what was used as a gasket between the carb & filter housing? I have to use either thin rubber or paper as the filter is easy to dislocate when bumped.

Nothing. When clamped to the top of the carb. it is a fairly air tight seal.

Wonderful job rebuilding the '38. I have a '38 2-dr that looks identical but it is the Master model with the straight front axle. I have owned it since 1972 and only occasionally get it out and drive it. Looks like NY plates on your car? I am near Kingston, NY.

I am getting close to retirement so I have ordered new tires and want to rebuild the brakes before I hit the streets. can you offer any advice on removing the master cylinder please? Do you take the clutch and brake pedal off first and leave them behind or does it come out as an assembly. I know mine hasn't been touched in more than 40 years and maybe never so it needs a complete rebuild or a replacement if I could find an NOS one. I also plan to replace all four wheel cylinders and refill the system with silicone fluid in the hopes it reduces the leaking and the rusting that plagues me every spring. Working underneath isn't as easy as it used to be for me but I plan to tackle it in the next month or so.
Thank you for any advice you can offer.
JIM

Thanks, and welcome to the site!
I used to live in N Syracuse up until '80, now I live in DE.




Disassembly was fairly easy once you unbolt the brake & clutch pedals from the levers. After you remove the chain & springs, unbolt the MC base, it comes out easily.

Putting it back together will take longer, as you have to find a way to stretch the return spring, which is very strong. I ended up making my own stretcher since it is pretty long. Check to see if the brass bushings for the brake/clutch levers need replacing.




If yours isn't corroded inside, you can rebuild it yourself with a kit that's about $15, and a new light switch is about $10. I don't know about the bushings, maybe $8 each. Inspect the cylinder for pitting.



Silicone will be better for the parts, but, not for your leg. Bleeding air out of silicone can be tricky, and the pedal won't be as hard as you would expect with DOT-3 fluid.


Very true. I ended up getting the really big jack stands from Harbor Freight, and 24" clearance really helps, although you have to be sure the stands are in the right places.

I have used silicone fluid in several cars and never had a problem in "getting a pedal".
Because of the silicone I had to replace the brake light switch in my '39 every few years. It insulated the contact inside of the switch and the lights will not come on unless you push really had on the pedal. Installed a lever type switch ( like Chevrolet used for 1942 and up) and had no more problems.

Did you bench bleed before installation?

Thanks for the advice. I can't wait to tackle this. Hope I find it is rebuildable.
I love the video of your test drive. That transmission growl in 1st gear sounds identical to mine. Looks like the car runs and stops good. You are to be commended on the great job you are doing on this car -fantastic attention to detail. The paint your are using looks really great.
It should be a real head turner when finished.
JIM

The 'donor' '38 that my father got came with 6 wheels. For painting practice, I grabbed one and cleaned it up. Painted it in Gunmetal grey.

The whole time I was working on it, something seemed off. finally figured it out...it's not the same wheel as the ones on my '38.

Below is a picture, the wheel on the left is original to my '38, and the one on the right came from the donor parts bin. Looking carefully, you can see that the one on the left has more horizontal holes than the one on the right.

Both fit my '38 well, but what is the one on the right for? Later model years?

The 1937-1938 wheel had eight slots, the 1939-1948 had four.