Durability mods

[cnicol]

I thought I'd share some durability modifications.
1) LM clutch cable. 65-68 clutch cables often break at the ball-end under the dash. When the ball "freezes" in the lever, the connection between the ball and cable bends and flexes whenever the clutch pedal is used; eventually it breaks there. If you keep an "eye on the ball" and keep it greased, that helps but to really put it to bed, switch to a '69 cable which has a heim joint instead of a cast ball. To make this work, you have to remove one side of the fork (it's a welded-on tab), add a 1/8" shim, and weld it back together.

[All Corvair car models] The accelerator pedal pivot in the tunnel is flexed every time you push on the accelerator pedal. Extra points if you're pumping the throttle for a first start after rebuild or long storage. Eventually the flexing starts to work the sheet metal floor and the pivot breaks off. This issue can be avoided by drilling and tapping the pivot bolt-head and adding a forward-facing strap to brace the pivot to the tunnel. With support on both ends of the pivot-bolt, there's no flex and the thing lasts forever.

[All Corvair cars and trucks] The wiper switch provides grounds for high speed, low speed, and washer functions. To make this work, the switch itself needs to be grounded to the dash. Switch body to dash is pretty reliable but switch internal circuits are connected to switch body using an internal brass blade that's riveted to the internal contact board but merely "rubs" on the inside of the pot metal switch body. Over the years the blade relaxes and/or the pot metal recedes where the blade rubs and the switch "goes bad".



The rivet is externally accessible for soldering. I solder a ground wire onto the rivet head and then run a wire to the dash frame where I terminate the wire with a loop terminal and screw that loop terminal to the dash frame. An independent ground wire makes the wipers and wiper switch much more reliable.

What durability modifications to you make and recommend?

[66vairguy]

Thanks Craig.

I do the WIPER SWITCH GROUND on my cars - a great fix as sooner or later the wiper switch to dash case ground deteriorates due to corrosion.

I like your ACCELERATOR PIVOT BRACE! I'll do that on my cars. I'll also suggest replacing the "toothed" rubber bushing with solid rubber bushings. I never could get the secondaries on a 140 to open fully until I got rid of those "toothed" bushings that collapse under pressure. Using a solid rubber bushing results in all four carburetors opening fully! No additional vibration was noticed at the accelerator pedal.

[cnicol]

Hmm... 79 views and only one response? Anyone wish to post their thoughts or practices? I'm sure there are many who would find your ideas useful and interesting.

Here's another one of my durability mods: Main Fuse to battery

Corvairs made prior to '67 had no fuse protection for the "big red" main power wire that spans and connects the alternator/battery/fuse panel/headlight switch/and lighter.
I add a hidden 60-amp main-fuse between the battery and regulator (EM/FC) and battery and LRPT junction block (LM)
In the case of a short anywhere in this circuit, the fuse isolates the relatively unlimited battery power from the circuit and thus prevents a meltdown or fire.

[66vairguy]

Craig --- I also install a fuse on the main power wire and on LM cars I use the fuse holder to by-pass the bulkhead connector.

As the bulkhead main power connectors corrode over time they get hot conducting amperage and then the plastic plug melts and contacts get loose and suddenly NO ELECTRICAL POWER. Great reliability LM upgrade to remove power wires from bulkhead connector and join them with a fuse.

Another upgrade is the headlamp grounds. Headlamps (or bulbs) are glass with a ground terminal. A "skimpy" ground wire goes from the headlight socket to a rivet on the headlamp aiming frame. That frame is screwed to the bucket housing that is screwed to the body. Convoluted ground path that slowly corrodes over time. I've surprised folks complaining about "dim" Corvair headlamps by improving the ground to make headlamps brighter.

I run a 14 gauge (16 gauge with stock halogen sealed beam) wire from EACH headlamp socket ground into the trunk and attach the ground wires to clean sheet metal.

[caraholic4life]

Here's another one of my durability mods: Main Fuse to battery

Corvairs made prior to '67 had no fuse protection for the "big red" main power wire that spans and connects the alternator/battery/fuse panel/headlight switch/and lighter.
I add a hidden 60-amp main-fuse between the battery and regulator (EM/FC) and battery and LRPT junction block (LM)
In the case of a short anywhere in this circuit, the fuse isolates the relatively unlimited battery power from the circuit and thus prevents a meltdown or fire.

Strategically placed, the fuse when removed could also be utilized as an "Anti Theft" device/deterrent.

[Scott H]

Good stuff
Thank you for posting it. I'm going to look into the throttle bracing mod on my car.
I relocated the battery in my car and I added fuses inside the battery box in case anything shorted the long cable to the rear.

[66vairguy]

Good stuff
Thank you for posting it. I'm going to look into the throttle bracing mod on my car.
I relocated the battery in my car and I added fuses inside the battery box in case anything shorted the long cable to the rear.

I have my battery in the trunk with a negative cable switch to disconnect it. I use a fuses in the engine compartment to protect the alternator and main supply to the fuse box.

A fuse on the main cable to the starter would have to be fairly stout. While starter run amperage is stated as 58 Amps plus the solenoid hold in amperage of 10.5 to 12.5 Amps, the surge amperage when the starter is first engages amperage can surge to 280 Amps!!!!!

[RexJohnson]

All of the late model headlight wirings that I have seen ground to the bottom screw that holds the headlight aiming frame. No rivet involved. Yes, it still has to find its way from the bracket to the bucket and then thru the screws to the body.

[cnicol]

Another upgrade is the headlamp grounds...
I run a 14 gauge (16 gauge with stock halogen sealed beam) wire from EACH headlamp socket ground into the trunk and attach the ground wires to clean sheet metal.

I like this one! Headlight wiring and grounds are both sketchy on all Corvairs.

[66vairguy]

All of the late model headlight wirings that I have seen ground to the bottom screw that holds the headlight aiming frame. No rivet involved. Yes, it still has to find its way from the bracket to the bucket and then thru the screws to the body.

Guess I'll have to go look, old memory ya know ---

[vairmech]

For those of you that add protection to the main circuit DO NOT use a self resetting circuit breaker. There is a reason it blew in the first place and if the breaker keeps on resetting it's self that you could cause a fire. Always use a fuse of the correct size.
The big red #10 wire is really only rated for 30A but will take 40A for a while. I never put more than a 50A fuse in line there.

[66vairguy]

For those of you that add protection to the main circuit DO NOT use a self resetting circuit breaker. There is a reason it blew in the first place and if the breaker keeps on resetting it's self that you could cause a fire. Always use a fuse of the correct size.
The big red #10 wire is really only rated for 30A but will take 40A for a while. I never put more than a 50A fuse in line there.

Good advice, but manually reset circuit breakers are O.K. Any thermal fuse will have voltage drops due to resistance as the amperage increases. There are some advanced magnetic breakers that minimize voltage loss, but the good ones are pricey!! I'll add that maximum amperage design requirements are NOT to protect devices, but to PREVENT FIRES.

Wire amperage ratings are complicated and why you see different amperage numbers for the same wire size. The critical maximum amperage is were the insulation starts to fail (melt or catch on fire!!!!!). A lower amperage rating is calculated on voltage loss per length and that depends on if the wire is solid or multi-strand. One reason it is difficult to get the full alternator output up at the headlamps is due to the LOOONG wire from the engine up to the headlamp switch and out to the the headlamps. Some run a second 10 gauge wire from the engine compartment (alternator/battery) up to headlamp relays controlled by the headlight and dimmer switches. NOTE: In a Corvair anything over 30 Amps over 12 feet with a 10 gauge wire will result in a voltage drop (loss) that is considered excessive by some guidelines (older cars are notorious for being designed with wide voltage tolerances).

ANYWAY ------ Yes a 50 Amp fuse on the supply wire is a good choice with a 10 gauge wire. Better yet, if you are running a lot of electrical loads and a 63 Amp 10SI alternator, then install a second 10 gauge wire up to an upgraded fuse box. Calling Craig Nicol!!!

On my cars the A/C compressor and fans run off relays fused in the engine compartment (with an additional 10 gauge wire off the battery/alternator junction). The battery is up front in the trunk and the headlamp power for the relays comes off the battery and is fused separately. That way I was able to keep the stock fuse box under the dash (it is new with a new stock wiring harness). I'm not saying that is the best way, just another way of optimizing the electrical system.

[cnicol]

Definitely concur: Battery main fuse should NOT be a self resetting circuit breaker.

Heres another durability-mod that applies to early models: Improved tail light grounds!
One way is to solder a wire to the lamp socket and ground that wire to the inner fender. Problem solved!

Stock grounding is really sketchy as it involves four mechanical joints (bulb to socket, socket to reflector, reflector to braclet, bracket to body). Dirt, rust, galvanic corrosion, and mechanical looseness all conspire against lamp function..

[66vairguy]

Definitely concur: Battery main fuse should NOT be a self resetting circuit breaker.

Heres another durability-mod that applies to early models: Improved tail light grounds!
One way is to solder a wire to the lamp socket and ground that wire to the inner fender. Problem solved!

Stock grounding is really sketchy as it involves four mechanical joints (bulb to socket, socket to reflector, reflector to braclet, bracket to body). Dirt, rust, galvanic corrosion, and mechanical looseness all conspire against lamp function..

ABSOLUTELY --- I forgot how many lousy EM tailights I've fixed by adding a ground wire. Cleaning the tail lamp socket reflectors helps too!

I also add a ground wire on the LM sockets, although they are not as bad as the EM. NOTE: many of the parts store LM sockets have flimsy metal ears and the socket fall out!!! When I bought my engine harness from M&H I mentioned this and they told me they had the same issue and had to pay EXTRA to get the company who made the new sockets to to use a heavier gauge steel!!! --- M&H will not sell separate sockets.

[jjohnsonjo]

Good ideas, back in 1995 my then 10 year old clutch cable broke at the ball. I put the ball in a drill press and drilled the cable out with the same sixed bit. I then put a 2" stainless bolt through the hole it the ball and then "U" bolted it to the broken cable. Lubed it , here it is 2025 and its still working fine. The length of the bolt in the ball to forces the ball to pivot in the slot rather than flexing the cable. No new cable $$ and no install time.

[Frank DuVal]

Ah, the metal shell of the taillamp socket (and parking lights in early/FC also) coming out. I fix that by running an #4 sheet metal screw (1/4 to 3/8" long) right through the plastic housing (on a side not so visible) to press against the metal shell. Once I do that I don't need to run a ground wire. I've fixed a lot of them this way.

If replacing the points wire on the distributor, use Test Lead wire. Very flexible.