"How many of our fellow forum members have you assisted, or is your only function on the site being a slow fisherman?"
Actually I'm no expert in any of this but I've tried to be helpful when I could.
Guys on Stovebolt are often VCCA members and some have contacted me about this article that appeared in the May 2009 VCCA monthly magazine:
1936 Chevy 1/2 Ton Pickup Modifications and Parts Substitutions
Ray Waldbaum #3855 of Santa Rosa, California — Email
[email protected] In the course of owning the same 1936 Chevy high cab pickup since 1965, I have discovered some mechanical modifications and parts substitutions that made this truck run better and made it safer and easier to drive. Some of these modifications were made over 35 years ago and the details, such as part numbers and exact dimensions of fabricated parts, were not recorded at the time. Therefore, some of the following information is general. Some of this information is probably applicable to other Chevys of this era. I am not a professional mechanic or machinist and all of this work was done in my home shop. My shop is equipped with a small metal lathe, small milling machine and various welding equipment, including a tig machine. However the tools that were most useful in stumbling onto this information were the telephone and various catalogs along with a perpetual curiosity about what’s out there that could make this truck work better.
Window Regulators The original window regulators had a single arm that raised and lowered the windows. Window regulators in later model trucks, through 1946, have two arms and work much better. The two arm window regulators are a direct replacement in the 1936.
Door Window Bottom Seals Porsche 356 seals are a perfect fit.
Fuel Filter The 1935-36 fuel pump has a fine mesh screen at the top of the sediment bowl. A much more effective part, and a perfect fit in the sediment bowl, is an AC gasoline filter element GF 149, AC part number 854567.
Fuel Pump Diaphragm Reviewing obsolete Ford catalogs indicates that 1930s era Fords used the same basic fuel pumps as Chevys, and individual parts like diaphragms are available from Ford restoration parts suppliers.
Carburetor Float Bowl Cover Leaks Leaks are chronic on these W1 carburetors because of a poor seal between the float bowl and float bowl cover. Various, difficult to accomplish methods of repairing the float bowl covers have been described to me. A quick, simple fix I discovered is Permatex® flexible anaerobic sealer, item number 51817 applied to both sides of the float bowl cover gasket. Permatex® technical advisors have told me that, although this product is not intended for use in carburetors, it is highly resistant to gasoline and it sure cured my leak permanently.
Ignition Points The original points are 2-piece units. Delco point set D105P is a one piece point set that fits perfectly into many makes of cars, including Chevys, from the 1920’s through the 1960’s. This point set is abundant and inexpensive on eBay.
Steering Gear Lubricant When I first restored my 1936 in the early 1970s, I was unaware that there was special GM steering gear grease. I mistakenly used other grease and it wiped off the gears, resulting in dry gear contact and creating high steering effort. I solved this problem by machining the steering sector housing for the thinnest, narrowest oil seal with the correct inside diameter that I could find in a seal catalog. That seal allowed me to use transmission gear lube in the steering gear box, improving lubricity and greatly reducing steering effort. In the approximately 35 years that seal has been in, it has not leaked a drop of oil. In about 2006, while rebuilding the Vega steering box in another one of my toys, a Chevy powered 1932 Ford roadster street rod, I discovered that GM steering gear grease is specified for use in GM manual steering boxes. That grease meets GM specification GM 4673M and carries GM part number 1051052. The bad news is that by 2006 none of this product was in stock at any GM dealership anywhere on earth. A call to the Shell Oil Company technical center put me in touch with a lubrication engineer. He cross referenced the GM specification GM 4673M to a Shell oil product called “Shell Alvania EP 1 Grease MC 2041SIPA” that fully meets the GM specification. Again the bad news, this product is not carried by any retailers in single cartridge quantities. However a group or a car restoration supply store could buy the minimum quantity and split it up. I got my hands on some and there is no question that it is the right stuff. It has the viscosity and appearance of mustard, while chassis grease is more like peanut butter.
Tierod Ends The original tie rod ends were complex, spring loaded, extremely worn out pieces that created a lot of looseness in the steering. Researching Moog suspension parts catalogs disclosed tie rod ends with the same female threads and a taper identical to the taper on the original ball studs. The Moog part numbers (35 years ago) were ES29R and ES29L. Making this conversion required grinding the peened end off of the original ball stud tapered shank, allowing the tapered ball stud shanks to be tapped out of the steering arms and pitman arm easily. These
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tierod ends were a direct replacement on the tierod. Use of these tie rod ends on the drag link required that the original drag link be discarded and a piece of steel be threaded, right-hand threads on one end and left-hand threads on the other end to accept the tierod ends and allow adjustment of the drag link length to perfectly center the steering wheel spokes. This was easily accomplished on my small lathe. These modern tierod ends, along with rebuilding the steering box with new worm gear bearings and sector shaft bushings, removed all of the looseness from the steering gear and linkage. My truck is a driver, not a trailer queen, but at the 1976 National VCCA meet in Colorado Springs where it won 1st in Class T-2, the judges did not notice these non original tierod ends or the homemade drag link. Apparently these parts look very original.
Exhaust Manifold Heat Riser When I assembled my engine, I got the heat riser working perfectly. However, it very soon began to stick and I heard from others that they had the same problem. Use of various lubricants, including ones advertised for this application, was completely ineffective. Finally, I bit the bullet and removed the manifolds to create a permanent fix. That consisted of removing the original, rusty heat riser valve shaft and duplicating it in stainless steel. This is not an exotic material. In fact, a stainless steel bolt from a hardware store would work. To make sure this exercise would not have to be repeated, I also drilled the shaft holes in the exhaust manifold oversize and made stainless steel bushings that are a slight press fit in the manifold and a free fit on the shaft, allowing easy movement but no leaks. That proved to be an effective fix and there has been no sticking or leaking in the following 25 or so years.
Transmission Gear Oil Long ago I noticed that my 1936 shifted best when cold, while the oil was “thick.” This transmission was carefully assembled with all new synchronizer parts and shift forks and all clearances were adjusted to bring them into the middle range of the specifications. This suggested that a higher viscosity oil might work better because it is probably what the 1932-36 synchromesh transmission, with its loose clearances and primitive design, was designed for. To check this theory, I bought some so called 600 weight oil from the Filling Station and tried it. Although it still does not shift as effortlessly as a modern car, the shifting is much improved with the more viscous oil.
Transmission Speedo Drive Gear Seal This is not something that applies to the 1936, but rather to the 4-speed manual transmission in my 1978 El Camino and the Chevy 2004R overdrive automatic transmission in my street rod and probably countless other GM applications. These plastic gears drive the speedometer cable and are contained within a pot metal or steel sleeve with an oil seal. When this seal
wears out, leakage occurs. GM does not sell the seal separately and the entire sleeve/seal assembly would have to be replaced to cure the leak because the seal has a weird outside diameter that does not match any available seal. In addition, the sleeve/seal is probably obsolete and unavailable anyway. However, boring the sleeve inside diameter a scant 0.010” or so oversize (I don’t remember the exact dimension) allows a common seal, available from any bearing supplier to be used. The exact dimension can be determined by measuring the stock bore and rounding it up to the next common size, like 5/8”, 3/4”, etc. This allows a quick, easy inexpensive fix for that oil leak.
Brakes So called “Organic” brake shoes/linings have been all that is available, except for drum/disc eating metallic shoes/linings, from auto parts stores for decades because of the health risks attributed to asbestos. NOS asbestos shoes and linings are abundant and inexpensive on eBay and have a much higher friction coefficient than “Organic,” giving greatly improved braking. Converting from “Organic” to asbestos feels almost like adding a vacuum brake booster. I hope that this information is useful to some VCCA members.
What’s Next? The next quest on my 1936 pickup is trying to figure out a way to adapt in a later year differential gear set with a more freeway friendly gear ratio. This would involve changing from the present spiral bevel gear orientation to a hypoid orientation. If any VCCA members have any information concerning this, please pass it on. The one “expert” opinion I’ve gotten is that this can’t be done, but I’m not ready to give up yet.
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On Stovebolt.com I learned from Pre68 Dave that a 3.55 rear gear conversion in my ’36 PU would work if I used a ’37 Chevy car rear axle. That information led to successful completion of the 3.55 conversion and posting on VCCA Chat of this:
http://vcca.org/forum/ubbthreads.php/topics/334876/1936_Chevy_3.55_rear_gear_convPeople on Stovebolt.com have contacted me with specific questions about this project.
Others on Stovebolt.com have contacted me about the 1934-36 Chevy truck fan shroud that I recently found after a 40+ year search for that very rare accessory.
The 1936 Chevy Owners forum recently posted this information on my tandem master cylinder conversion:
Dave,
Here’s the story of putting a tandem master cylinder (MC) on my ’36 Chevy high cab pickup. The first step was finding a compact MC that would fit into the confines of the original MC/pedal mount casting and has a 1” bore. This is the casting.
A mid 1980s Jeep MC fit that description. Here are some part numbers:
Dorman M56193
A1 Cardone 13-1292
Wagner MC 56193
Bendix R11373
A port at the bottom of this MC is plugged but its threads are 1/8” pipe, the same as an OEM 1936 Chevy brake light switch that screwed right in. The OEM wiring harness (actually a NOS 1937 Chevy pickup wire harness that I found when I did the restoration in the 1970s) reaches this revised brake light switch location. Is that too cool or what?
The wide ears on the replacement MC were milled off to make it narrower and new mounting holes were drilled as close as possible inboard and tapped 5/16” 18 TPI. My son, a mechanical engineer, calculated those two bolts would have more strength than the pushrod clevis pin and thus was adequate provided Grade 8 bolts were used.
Then I made a bracket that the narrowed replacement MC could bolt to and the bracket in turn could be bolted to the original casting with two 7/16” bolts. The Allen head bolts thread into the MC casting and a nut will also be placed on the bolt threads that protrude through the MC casting. Here’s an interesting side note on the welding, done with a Miller AC/DC tig/stick machine running at 140-160 amps. This bracket is stick welded with 5/32” 6013 electrodes, chosen for stick’s speed although it doesn’t make the “stack of dimes” beads that characterizes tig. Because this is a critical part all joints were welded on both sides. My wife showed me our electric bill and even this small amount of welding showed up as a daily “spike” on the bill. We must be really small users of electricity for this little project to spike the daily use noticeably.
Then in a rare, for me, moment of brilliance I thought to test the OEM MC to see if it has a RPV. That was easily accomplished using some tubing scraps, old fittings, a Schrader valve and a pressure gauge. The actual position of the vertical part of the bracket was dictated by the need for gusset plates in front of the MC, clearance for the bolts mounting the fabricated bracket to the original casting and clearance between the lug on the bottom of the MC and the original casting.
Next was determining if residual pressure valves (RPVs) would be required. I found conflicting information on this and couldn’t decide whom to believe.
This test showed that the OEM 1936 MC has a 15 pound RPV. The replacement MC has no RPVs so Wilwood 10 pound RPVs for each output line were bought, along with fittings to adapt the Wilwood RPVs to the ¼” brake lines used on the ’36 Chevys.
Next was making new hard lines that would follow the OEM brake hard line route along a cross member under the back of the transmission from the MC to a “T” fitting on the right frame rail. There each of the hard original hard lines was disconnected from the “T” and connected to the two new hard lines with ¼” inverted flare unions, completing the hydraulics.
In the bottom picture a union is used to hold the new front brake and rear brake tubes in position for the photo. In the actual installation each of these two new separate hard lines are attached with a union identical to the one in the picture to the OEM front and rear brake hard lines.
Next was making a push rod. That was done with a modern 7/16” diameter pushrod with its end cut off, turned to 3/8” diameter, and threaded 3/8” 24 TPI on my lathe to use the OEM push rod clevis. Reducing the diameter of the front of the pushrod to 3/8” and welding the bracket were the only parts of this project that could not be done with common hand tools. Because the location of the replacement MC is rearward from the OEM MC location, the pushrod is longer.
The OEM MC and pushrod combination limited the upward travel of the brake pedal in the cab to match the level of the clutch pedal. The new setup did not do that and the pedal rose to a level above the level of the clutch pedal. To limit the upward travel of the pedal this spacer block was attached to the underside of the floorboard.
Finally, the cutout in the floorboard above the MC had to lengthened and widened slightly because the tandem MC has a long cover rather than a cap and the tandem MC is mounted rearward from the OEM MC location. A new sheet metal cover was made to cover the enlarged hole. The plate nut I put in when I did this restoration in the 1970s was extracted and reused “just cuz” for old time’s sake even though I have some new ones.
This was a simple project but one with many steps. By doing it in small bites it got done. That actually happened by necessity because during the project there were some weather related issues to deal with like power outages, keeping drainage ditches and culverts open and flowing, and mudslides and fallen trees closing our road and even blocking our driveway. Our phone has been out for almost 2 weeks but that’s not a bad thing. Friends can still email and there are no annoying telemarketing calls.
This weekend the weather changed and my unheated garage had sunlight shining in and it was no longer damp and as cold as a refrigerator. Yesterday my wife helped me bleed the brakes. That’s always a tedious job with DOT 5 (silicone) brake fluid because that stuff really holds onto its tiny bubbles but we “got ‘er done”. Today (January 30) we drove it to a local park for a quick picnic lunch, a round trip of about 25 miles. Everything works OK and there is no difference from the OEM MC in braking performance because both the OEM and tandem MCs have 1” bores and the same pedal is used.
My next project will be to put a 1934-36 truck GM accessory fan shroud on my pickup. This must have been a very rare accessory. I found a NOS bottom half in 1979 but it took another 38 years of searching to find the upper ½. A member of this forum had removed it from a ’34 1 ½ ton truck and had it hanging up in his shop. He very generously gave it to me.
Even though I’ve owned this ’36 pickup for over 50 years, no project is ever done and this one is no exception.
Most recently I've discovered that Lubriplate SPO-288 gear lube is a big improvement over so called "600W" oil in my '36 transmission. People have contacted me with questions about the cost and availability of that product.
So I have been glad to discover some new things and share them.
