1966 Corsa Convertible

[JohnDB]

Seemed to be the right time to get this started - I'm going to try to keep track of the things I do to this 1966 Corsa 140 Convertible - we'll see how it goes...

Here it is as of a few weeks ago when I became the owner:

Some background info on the car - mostly to try to keep track of it. My father bought the car in the summer of 1986 in the Broomall, PA area. He seems to recall that the seller was younger and maybe a bit over his head with the car. It was reported to have a cam installed, but since the install hadn't run properly. From a cold start it would be fine for about 20 minutes, then it would start to lose power and eventually die. It was undrivable until it cooled off and was good for 20 minutes again. It had a quick respray on it that was probably a few years old, but it looked ok from far enough away and it came with a bunch of parts.

I can remember chasing a lot of different things that might have been causing it to run so poorly. Ignition, carbs, timing, valve adjustments, and anything else you can thing of. Nothing really made a difference and the car sat in the garage between failed attempts. The engine in the car at this point (late 80s) is still believed to be the original, but with the cam installed and 4 primary carbs. As a "we tried everything else" move, we pulled the 4 carbs and put a pair of known good carbs off a 110 that ran very well and blocked the secondary ports. By some sort of magic this seemed to do the trick!

We ran the car is this config for a few years, and I remember going to the CORSA convention in Washington DC (1991?) in it! Not too long after, however, it all went south pretty quickly. On the way home from a small show in 1992 or so there was an odd noise and the engine quit. An attempt to restart it sounded much different and it turns out it had no compression. Into the garage it went, and there it sat while life got in the way for a while.

By now we also had a 2nd Corvair (1967 500 sedan) that my dad was using as a daily driver. It was also running a 140 and a 4spd that had been swapped in by a previous owner from a rusted out Corsa coupe. At some point the clutch was slipping too badly to drive any more and it sat in the driveway. The body on this one had been hit pretty badly at some point and put back together, but the repairs didn't hold up well and the front fenders were in a race to see which would rust off first. It finally got to the point where we pulled the power pack and sent the shell to the yard.

The plan was to pull the failed engine out of the convertible and put the running 140 in, then dig into the failed engine later. Life gets in the way again and the car and spare engine sit next to each other in the garage. After a while, we pulled the oil pan on the failed engine and found that the cam gear was spinning freely. It is very possible that it wasn't installed properly on the cam and that it was the cause of the poor running all along as the cam timing changed when it was hot. For a while it "stuck" in the right spot before it let go completely.

My dad got to the point where he wanted to drive the convertible again and decided it was time to get the engines swapped. We took the spare engine and car to the Corvair Ranch and they did the swap for us. It was running great again and he drove it around a few times. Not exactly sure why, but it still mostly sat in the garage. Time goes by again and it's 2021 already - now my folks are looking to downsize and I'm looking for a classic car project. The timing worked out well and now it is in my garage.

[JohnDB]

Current engine setup:

140 engine running the "Ultimate Carb Kit" that Clark's used to sell. I think these are Holly 5200 carbs (licensed copy of a Weber 32/36 from what I can tell). It runs well, but has some things I'll be working on. I'm not sure how old the filters are on the fuel inlets, and I'm not a fan of the rubber lines. When the engine was swapped there was a filter added in the rubber line behind the firewall, so I don't think I need the inlet filters any more. I was able to find a 1/8 NPT (carb inlet) to 1/4 inverted flare (fuel line) adapter and got 2 pre-flared straight lines to make new hard lines to the carbs.

The line to the left carb turned out pretty well, but my measurement for the right carb wasn't great and I ended up having to cut the corner and run pretty close to the dipstick to get it connected. No picture at the moment - when I started it to check for any fuel leaks, I noticed the belt was flopping around a bit like it was really loose. Then I noticed this (you can see my short fuel line a bit in the background, I ordered a longer line already):

On the plus side, there were no fuel leaks... Then I looked down at the harmonic balancer and saw this:

Better that it failed in the driveway I guess. That was last week and prompted a Clark's order.

[JohnDB]

And that brings us to today. All my parts arrived as well as the Blue Chip Tools balancer puller. I can't say enough good things about this puller - it works perfectly and is well worth it!

Once the balancer was out of the way, I needed to run a new wiring harness for the temp sensor in the right head and the oil pressure sender. The previous one was a creative setup, but the giant glob of solder would hit the distributor and make the temp/press come on and off sometimes:

The balancer wasn't as bad as I expected, but I don't think it would have lasted too much longer.

The seal also came out with no trouble and I cleaned up the area. Tomorrow will be the re-install of the seal and balancer, and I'm going to drop the oil pan to replace the gasket to fix a few drips.

[JohnDB]

Another busy and productive day. Got the seal installed first using the install tool from Blue Chip Tools - the combo of the puller and seal installer worked perfectly and I highly recommend them:

With the seal in place, I used the old bolt and a thin washer to put the balancer back on. It felt like it took forever, but there is only room to swing the wrench maybe a 1/4 turn each time. It pulled up very evenly and I swapped to a new bolt and new thick washer about half-way through. It seated all the way on and I got the bolt as tight as I could - no room to get a torque wrench on it.

Then it was time to drop the pan since the oil was getting changed anyway. A few of the pan bolts liked to drip, and they all seemed like to tighten up, but the next time I checked they were all a little loose again. I got the "Best for Aluminum Pans" gasket from Clark's. Off with the dirty (bolts already out in this pic):

Looks pretty good inside - turns out this engine just has an OTTO pan, not the deeper pickup - something to put on the list I guess:

After several hours of cleaning the pan and the bottom of the engine, I ran a tap through all the bolt holes to clean them up. They all seem to be good, but about half of the bolts had pretty lousy threads. A trip to a few hardware stores and no one has flange bolts (Ace had grade 8, for almost $3 each, no thanks) so I ended up with slightly longer hex bolts, flat washers, and lock washers for the whole pan. I stuck the gasket in place on the pan with a thin layer of Form-A-Gasket and put it back on the engine. Turns out the flat washers don't fit well between the fins on the pan, so I had to trim them a bit. A little thread sealer on each bolt and I tightened them up just until the split washer closed. I'll leave it sit until tomorrow and check them all again before adding oil.

Looks a bit better now:

Overall another good day in the garage and I think I'll have it out on the road again this week. Need to check the pan bolts, add oil and a filter, put the new fan belt on and it should be good!

[viewmaster]

That pan doesnt need the deep pickul, because its not a deeper pan. FYI.

Nice work, keep up the momentum. Sweet looking car.

-m

[JohnDB]

That pan doesnt need the deep pickul, because its not a deeper pan. FYI.

Nice work, keep up the momentum. Sweet looking car.

-m

Thanks, that's good to know. It looked pretty flat when I cleaned it out so the stock pickup makes sense. I think I was getting confused by some of the other aluminum pans out there.

Got a few minutes this afternoon to make some more progress. Went around all the pan bolts with a nut driver and all were still good, so I put a new filter on it and put 3.5 quarts of oil in it (1/2 qt. in the filter). It's been in there about an hour and so far everything is dry - Sanded the groove in all the pulleys a little bit just to be safe, and put a new belt on (Clark's wrapped belt).

Looking pretty good again:

In the picture above, you can see the fuel lines I made. I'm happy with the one to the left carb, but the right one was too short. I got another pre-flared line (20" this time, first one was 12" - and they don't offer one in the middle) and gave it another try:

It's better I guess, but now too long. A 15-16" inch would probably be about right so I might have to get the flaring tool out and make a custom one. For now I think this will work fine. Hard to tell in the pictures, but it clears everything by at least a 1/2".

It started raining pretty good, so that's it for now. Hopefully tomorrow afternoon I can get it off the ramps, fire it up, and check for any issues!

[joelsplace]

Good job getting rid of the rubber lines. Get the flare tool. Be cautious with the really cheap flare tools. They don't clamp the line good enough to make the flare. You'll be glad you have the tool since you'll be able to make the line the exact length you need.

[JohnDB]

Good job getting rid of the rubber lines. Get the flare tool. Be cautious with the really cheap flare tools. They don't clamp the line good enough to make the flare. You'll be glad you have the tool since you'll be able to make the line the exact length you need.

I certainly feel better with the rubber lines gone - and the extra filters of unknown age probably didn't help anything either. I think my dad has a decent flaring tool, and I've got the short line to practice with.

I was able to get the car off of the ramps today, do a final double check on everything, and get it fired up again. Wasn't too bad to get started and there were no fuel leaks from the new lines! Didn't seem to be any oil leaks either and I was able to go around the block with no issues. Checked the fan belt and tightened it up a little bit and took it for a longer ride.

No issues with the balancer or belt, but I'm still having issues with the temp/press light flashing. I thought the new sub-harness that replaced the fancy soldered wire would have done the job, but I've got some more troubleshooting to do.

And after it cooled off a bit it looks like the oil pan is still not happy. There is a little oil that looks like it is seeping out from the plug at the rear of the pan (temp sender port?). I probably should have pulled it and sealed it, but it looked solid when I was cleaning everything. I'll take a look again tomorrow and see if there are any other spots, but it's got to be better than it was.

[joelsplace]

In case you don't know: Corvair belts run very loose compared to other cars. You should be able to turn the alternator fan with one finger. Too tight makes them prone to coming off.

[JohnDB]

In case you don't know: Corvair belts run very loose compared to other cars. You should be able to turn the alternator fan with one finger. Too tight makes them prone to coming off.

That's exactly how I've got it tensioned - I can push the alternator fan pretty easily when it is cold. It'll keep an eye on it for the next few drives and won't be too surprised if there is a little stretch and it needs re-tensioned.

I had a few minutes tonight after work to dig into the temp/press light issue I'm having. From what I've read so far, the temp/press bulb is fed positive from the ignition switch, and ground comes from either the oil pressure sender or head temp sensor in the right head. When the key is turned on, and with the engine still off, the light should be lit because ground is provided by the oil pressure sender. Once the engine starts and there is oil pressure, the sender is no longer grounded and the light goes out. If the temp sensor gets too hot, it will ground and also turn the light on.

So far when I turn the key on but don't start the engine, the temp/press is lit so that's good. I replaced the mini-harness from the oil and temp senders to the engine harness and the light still comes on and off randomly.

I checked continuity to ground from the oil pressure sender with the engine off - it is grounded so it seems fine so far. There was no continuity to ground from the temp sender, so that also seems good. Then I connected to the wires on the engine harness and got continuity to ground on one and then both. Moving the connector around didn't seem to matter much and the wire looks ok. I moved the main harness connector around at the firewall a bit and that didn't change anything either. Next step was to disconnect the engine harness from the body harness - the continuity to ground dropped on both wires at the 2 position connector, so I think that means the body harness could be touching somewhere. I was planning to pull the tunnel cover to work on the shifter, looks like I'll have some more things to look for while I'm in there. I'll take a quick look under the dash too, but I have a feeling it's in the tunnel.

[joelsplace]

Sounds like you are on the right track. I'll bet the emergency brake cable has worn through the harness from incorrect routing or something obvious like that.

[JohnDB]

Got to thinking about this a bit more and took a look under the dash. From what I can see, the harness is secured in all of the tabs where it should be and it doesn't seem like anything is moving around. Thought about it some more, and realized that the bulb is completing the circuit and that is why I have continuity at the engine harness.

I removed the bulb, guess I'll need a new one:

With the bulb out, the wires in the engine harness no longer have any continuity to ground and it looks like the body harness is fine. Off to the flaps for a bulb (and I got a new oil pressure sender too because of how often I've read they fail).

Got back and installed the new bulb. Turned the key on, and now the temp/press light won't come on. Double check all the connections and got my daughter to watch the light while I tried to move the engine harness around. Nothing happened when I moved the harness around, so I went to the wire going to the oil pressure sender to ground it and she said the light came on. Pulled the wire off the sender and the light went out - that's good! Plug the wire back on and it flickered a little and then came on steady. Pushed on the connector a little more, and the entire top of the sender where the connector plugs in spun about halfway around the sender - the little rivet in the top was loose the whole time (circled in red):

For the moment I was able to get the connector to wedge itself to a spot that seems stable, but I'll swap the sender over the weekend. Took a short drive before it started raining too much and it's running pretty well

[JohnDB]

Got some more miles on it this week, but it looks like I'm still chasing an oil leak. It's not a big one, a couple of drips it seems like. Haven't gone too far under it yet, but it seems to be coming around the end of the pan, don't know if that means it's coming from much higher up or the oil pan gasket. Everything around the crank seal I replaced a few weeks ago still looks good, so maybe the gasket under the alternator/fuel pump bracket? I need to clean it all up in the area where the engine number is stamped and see what happens.

While I had it out yesterday I ended up in a pretty long line of traffic. Temp stayed under 400 on the dash gauge so that seemed fine, and it dropped pretty quickly once traffic started to move. Right about when traffic started moving though I had a pretty solid miss that has come and gone a few times. It feels like ignition, so I pulled the cap after everything cooled off. The cap looked ok, no obvious issues but it looks to have aluminum contacts - I've had issues with caps with aluminum contacts on a few Volvos before so I'll see if I can find one with brass contacts. The rotor, however, was covered in rust at the tip. It looked like the tip should be brass, but it seems to have just been colored to look like brass. I sanded it off a bit and when I ran it today it was all good. Plug wires seem a little on the stiff side, so I think I'll try to check resistance on them. And if I'm that far I should probably just pull the plugs too and see what they tell me. Something to do in the next few days anyway - along with the oil pressure sender I still need to swap. Keeps me out of trouble though...

[gbullman]

Sounds like you're making good progress. I still have a minor oil leak that I think may be the distributor seal, only part of engine compartment that is somewhat wet is all around the distributor. Planning to install a FAST XR700 at some point, will change the distributor seal then.

Best I can tell all of my work a ending a couple of weeks ago was a success. It was the little things that had the most enjoyment impact, the operation of all my throttle linkage is just what I had hoped for so happy about that.

Drove about 100 miles round trip yesterday pushing it on the interstate a little and all was good. Will keep expanding my trips and how much highway time until I'm confident there are no lingering issues.

Doesn't hurt that weather has been fabulous the last couple of days, a great time to get out in a convertible!

[JohnDB]

Best I can tell my distributor seal is good. I cleaned it up a bit and took it out for a while. Once the temp finally gets high enough I still have a bit of a miss, so I think some tune up parts are up first. Need to see what is still "in stock" in Dad's garage.

Here is where the oil seems to be coming from - this is after about a 30 minute drive.

I had the bolt circled in red out and fully clean and dry (ignore the orange to the left of that bolt, that was the previous color of the top cover). It is now covered in oil again - so does this seem like the gasket for the alternator/fuel pump mount? Would that drip down the back of the engine and down the back edge of the oil pan or would it get stuck in the skid plate?

[JohnDB]

Had a few minutes this morning so I decided to pull the Delcotron (way more fun than calling it an alternator) and replace the oil pressure sender. Got another chance to wipe up more oil from a different angle too - sender swapped and cleaned up as best as I could:

All the bolts that hold the Delcotron/fuel pump bracket are tight. Doesn't seem like the oil is coming from there but hard to say for sure right now. Got it all back together and had a chance to take it for a ride. Did about 30 miles and it's a mess again after I got home (which I pretty much expected).

This time, though, there are oil spots higher up on the turkey roaster - some spots even on the plug wires. The base of the oil filler tube is wet, maybe this is as simple as an oil cap? It looks ok and seems to tighten down, but maybe not well enough. I'll have to check the one on the other engine and see if I can get a better seal. I seem to recall the Corvair engine often pushes some oil out the fill pipe when the dipstick reads at the full mark - I was pretty careful to fill halfway between add and full - maybe it was still a little much?

Still has a miss that comes and goes - seems to be after about 15 miles when everything is good and hot. I pulled a couple of plug wires and the resistance tests within spec, but will probably order a set anyhow. I also noticed that the tach jumps around a bunch when it's missing. Not sure if that suggests it really is an ignition problem or if the tach is just acting up. The needle will swing 500 to 1000 RPM even when running at a steady pace.

Another question - is this part of the shroud under the distributor from a car with AIR?

Any reason I can't cover that hole with a small piece of sheet metal?