Showing posts with label corvette. Show all posts
Showing posts with label corvette. Show all posts

Wednesday, September 23, 2026

Gassed Up, and Ready to Rock

The tasks of the day started small, and ended up with a few big to-do's.

I took a few days off of work to work on the car.  First, I noted that the cooling fans (dual electric) are probably not done right.  So, I ordered a few parts to re-wire, plus to get a good switch to turn them on and off properly.

Next, I brought my neighbor over to help me get the timing set on the car.  Before, while talking with him, he kept saying "fuel, not timing".  But, since I had it somewhat running before, and only messing with the timing until I couldn't keep it running, it really had to be the timing. Right?

Really, right?

No. We worked on the car for a few days, checking plugs (one wire burnt), etc.

It very nearly ran a few times.  I spent hours using a syringe to squirt fuel into the carburetor fuel bays to fill it up to the sight holes.  The poor guy spent two days with me, and regularly said "fuel problem."

So, after getting tired of squirting gasoline into the fuel bays on the carburetor, and he again asked how the fuel pump was and if I verified that, I decided to look at the fuel filter (one of those fancy glass ones so that I can see how clogged it was getting.

Bone dry.  Sometimes, guys just don't listen, do they?  Okay, the pump is bad.  I looked at the Edlebrock fuel pumps, but opted for a Facet (I hear better things about Facet than I do Edlebrock regarding this style of fuel pump).  On Napa, it's a BK 610-1050 .

  • 32 gallons per hour
  • 4 to 7 PSI (perfect for a carburetor)
  • inline, and not in-tank, because I'm not dropping a fuel tank to hack together an in-tank and a fuel sending unit
  • While it is intended to push, this one can be set up close to the tank, inside the frame, and pull a little bit of fuel 

We'll see how this one performs over time, if it is sufficient. I already have a fuel pressure regulator, just in case, in position.

Knowing I need to get the fans into a better wiring position, and knowing I needed some electrical for the pump, I suddenly went into to-do mode for this, since I have worries. 

Here's the to-do's :

Better wire looms to prevent burnt wires.

I really need to get them past the headers, and the #2 cylinder is really bad on the angle.  If I run the wires between #2 and #4, it will burn, so I have to run the #2 wire over and around the exhaust pipe.  While here, I will actually use some of those heat covers, to see if that also helps.

Build a wiring harness for the electric fuel pump

I mapped out the wiring diagram, looking for a good spot to tap into for both the electric fuel pump as well as the cooling fans.  The best I could find on this car is the wire that feeds the HEI distributor, because if the car is running, those other two need to also be running (or be able to in the case of the fans).  There are two wires from the front of an HEI distributor, a brown one that routes to the tachometer inside the car, and a pink one that routes to the ignition switch.

So, I ordered some much-larger wire in "pink" so I can match, and then mapped out two and a half wiring harnesses.  (The half is because I'm planning ahead on the cooling fans).  First, arrange the components of the harnesses (including relays).

Then, cut wires to length and solder them together.

The wires were each done in a specific order so that I could also slide heat-shrink tubing on and seal them up.

Once each wire was soldered into place and sealed up, I commenced wrapping with a wiring harness fabric tape.

Now, I do have a "wiring harness".  It can't do much until I connect all of the relays.  Again, laid out with relays "in position".

The Painless wiring harness (50102) I used has a ground wire that is short.  But, since this body is fiberglass, there's not a whole lot I can do, because fiberglass does not conduct as well as we all hope.  So, a few relay housing wires get swapped so I can run a longer black wire along with the yellow one for the pump.  I ordered the inserts that can be put into the relay housings, and crimped them into position.  I then soldered the connectors because I have this odd fear of corrosion getting too far in, and also getting shaken loose.  So, soldering.


One issue is that each relay housing has two different types of connectors inside, so I had two different connectors.  The connectors were the 6.3mm (they are really 1/4" connectors, but the invasion of the oriental supply chains force measurement in metric).  Now, one of them I ordered had tabs on the back that were too long.

Rather than ordering new ones (and hoping I could find perfect ones because no one lists the actual data on the tab length), I just grabbed the dremel and chopped it off a little shorter.  Then, replace the wires (I'm using uniform colors, so someone using a wiring diagram for this car will know exactly what it is).

Granted, at this point, a basic relay and relay housing would have been cheaper than a Painless harness, but I was already there, and I didn't want to order and wait again.

Next, I added connectors on the ends for things like the fans as well as the fuel pump itself, and also the pink ignition wire running to the distributor, and next I tackled getting it installed.

I cut the pink ignition wire to the distributor, and installed a connector on both ends of this, then clipped everything into place.  It took a while to get it routed where it needed to be, to get the fans hooked up, and to get the wires to the fuel pump installed.

Harness is looking good! 

Electric Fuel Pump

Next, it was time to get the pump installed.  I did remove the old mechanical pump, and installed a pump block off plate.


Now, knowing I have to install better lines, I converted two of the socket head bolts for the block off plate into "studs" by using stainless all-thread and machining a round-but-hex stand off.

I can use these now as mount points for a lower bracket securing the fuel lines to the block.

I wanted to place the pump along the frame rail, however, I had only 8" of length to place it and it would have hung under the frame about a half inch.  This was unacceptable to me.  So, switching things up, it has to go into the tank.  That means, I have to get to the fuel sending unit, and install an in-tank pump if I go electrical.  Since I'm also doing this with the future to install fuel injection, it also means I need a fuel pressure regulator that will adjust low enough for the carburetor, but will also have a high enough pressure for when this gets injection.  Now, Tanks, Inc sells full tanks ready to go for the C3 Corvette, but surprisingly, this does not list a late model C3.  Holley sells a fuel pump sending unit that is a direct replacement, and that may be an easier way to go.  But, I don't want to spend $500 when I can use the pricier form fuel pump for $60 and some brass fittings.

So, drop the tank.  Swear a little because the bolts holding the tank straps in place are spinning freely and the bolts won't come loose, so run to Harbor Freight and grab some curved wrenches, then take them to the bandsaw and chop them so I can get them into the area I needed to lock the bolts.

Okay.  Let's try again to get the tank out.  Woohoo!



While there, I noticed that the sending unit did NOT have a gasket.  This is likely because the fuel tank originally had a bladder inside that also clipped over the edge.  Without it, I have to create one.  I spent time trying to figure out how to photograph and use a laser cutter, only to realize I could be done before I even finish preparing images.  So, a 12"x12" piece of fuel-safe rubber and a compass with numbers was implemented.


I then used a few of the wood clamps to put it into place on the sending unit, and then traced the holes using a silver-colored sharpie (because it shows up best on black).


Drilled and re-aligned to the sending unit, it will be perfect.. 

Now I can get back to modifying the sending unit.

I ordered some tube to create a bracket, however, I realized I can easily pull the sock off the tube, and add compression fittings to simply hook a pump up.  Granted, I did have to turn off the hex on a 3/8" hard-line to turn it into an adapter.

Then the compression adapter mated up and allowed the pump to be connected.  I drilled two holes for the wiring for the pump, and installed it.



I simply needed to finish the wiring to connect the engine bay relay to the fuel pump and install the tank, and connect the tank up to the fuel lines into the engine bay.



Yeah, I built an "adapter" (really, it's a restrictor) to force return lines and feed lines through the same diameter.

With that installed and fuel return and fuel pressure regulators and filters were all installed, it was time to get back to timing this thing. 

Cooling fans

On the wiring harness war front, I had one issue that was critical, but at the same time, not critical - mounting.

The double-relay assembly needs to be mounted securely so that it doesn't bounce into the fans or onto the exhaust and get fried.  This means potentially designing a part that fits on a non-uniform, curved surface.

I loaded up the Skanect tool, grabbed the XBox Kinect and the USB adapter, and ran a quick scan on the engine compartment.

Exporting to a PLY file (a triangle mesh), I could get a basic 3D model of the fender I need to fit this to.

First step was getting the orientation proper.  I created a cube that allowed me to adjust for size.  I shrunk the cube to fit in a specific spot, then found my scale options (I have to increase this 888.15789473% once I have it defined properly).

I tinkered with the cube until I got it the right size (I'll re-scale it once I have it proportionally good).  Then, I added tabs to create a basic bracket (no thread holes yet because I don't know the angles quite yet for perpendicularity to the inside surface).

The next step on this was to convert the mesh object to a solid.  Knowing how many faces, it is exactly why I avoided re-sizing the scan and instead re-sizing the bracket both before and after).  This took about 8 hours to process.

Then, it was simply a matter of a boolean operation to cut the scan from the "bracket".  Again, because of how many faces are involved, this took a long time.  Be patient. 

Clicking the mesh object in the tree while in "Part" view, and then clicking "Part" and "Convert to Solid".  I used a 0.100 tolerance for sewing the shape.  Note that this will take a lot of processing power, so be very patient.  If it works, you can move on.

Then, it was simply a matter of a boolean operation to cut the scan from the "bracket", or so I thought.  Again, because of how many faces are involved, this was taking a long time, so I exercised patience... until FreeCAD aborted.

[sigh].  A different approach?

Nope, after taking a different approach, FreeCAD kept aborting on me.  Apparently, there were too many faces in that scan that I was using for a reference.

So I gave up and bolted the relays directly to the fender.  I'd already installed dual fans, and new wiring, so it was a matter of putting the right connectors on the fans, and hooking them up.

Now, that gives me a good connection, and I trust the cooling system now.

Fix the starter solenoid wire (the purple one hanging down).

While working on the timing, I noted the solenoid wire from the key switch was hanging down at the starter.  This was fine, since putting the car in drive enabled the other wires and I was using a remote switch (I'm not climbing in and out of the car that many times while troubleshooting). So, I patched that one up.

Testing

Now I can finally get back to trying to time this thing.

Tuesday, May 5, 2026

Flushing The Radiator

While preparing to wire in dual electric fans on a switch, I knew I needed to give the cooling system a clean bill of health.  I mean, what's an evening compared to peace of mind?  (Or is it supposed to be a piece of mind because I may have lost it?)

I slipped by the big box home improvement store, bought two 6-foot garden hoses, two 1-1/4" PVC reducers (to 1/2" female pipe thread), three short  1/2" pipes (2" in length, I think), one PVC ball valve, and two garden hose adapters (one male and one female, both with a female 1/2" pipe thread on the other end).

 I screwed it all together, and had a solid system, ready to flush the radiator.  I cracked the thermostat housing, and... realized a previous engine owner had mixed orange and green antifreeze (I'd filled with water at one point, but never added antifreeze).  Orange and green antifreeze do NOT mix well!

Here's the thermostat.

I think it's pretty safe to say, don't mix orange and green antifreeze.  Any way, it took some time to get all of that cleaned out, including removing the thermostat (so I can flush the engine side, of course - if that's still in there, it won't open, and you won't get any flush).  Then, it was time to flush the system.  I started with the radiator side, and put the ball valve host between the house garden hose connection and the top of the radiator (connected from the engine side), and the other hose at the other end, with the hose in a bucket.

Turn on the house connection, then turn on the ball value, and it pushed water through.  Initially, it came out a thick-ish (it wasn't really thick - it was still very much liquid), but definitely not transparent.

I emptied one bucket, filled the next, and the next one came out a little cleaner.

I switched sides to flush from the other direction (still on the radiator), and ran two more buckets, until I was satisfied with clear water.

I disconnected my lines from the radiator hosts and re-attached them to the engine, then took off the radiator side in order to flush the engine.  Again, I did this from both ends, flushing coolant from both directions.

Again, repeating until I had clear water.

Once I was satisfied that water was clear from both directions, I stopped.

I detached from from the hoses, put a new thermostat (95-degree) with switch and sensor threaded holes, and now I'm ready to run this engine once I get the fuel pump in.

Saturday, September 30, 2023

Plate and Light - Installed!

 Finally, after all that effort (both the kind that had results and the kind that didn't result in anything that was really needed), I have the place installed on the car!

Now I can legally drive!

More License Plate Work - Light Mount

 I started digging around getting the license plate light installed, and in the assembly manual, there is this little gem :

It doesn't say much about how it got into position, and my memory is fading, so I cannot answer how this little bracket is installed. With having to create the mounting bracket underneath, I'm starting to think I now have to custom build a bracket to fit this aftermarket bumper cover.  Okay, I'm going to treat this like we did the gasket, and create a paper template, print to make sure it fits, then print and glue to some angle iron that I can use to mount this thing up.  I'm hoping I don't have to remake the bracket, but we'll see.

First, it's time to grab a photo and take some dimensions.

With this, I fed this first into GIMP (the open source photo editing software), and "unskewed" it (rotating and altering how the image sites to simulate a perpendicular photo - symmetry is key).  Next, I open up Inkscape (open source Scalable Vector Graphics editor), and proceed to trace the image.

Once mapped out, it's time to make sure we got the size right.Select everything, and then make sure, using the measuring tool.

With accurate measurements, it's time to perform the object math - subtracting the pieces to get exactly what we want.

Finally!  We can now print this out, cut it, and test fit it.  (Note, I'm too lazy to get out the vinyl cutter and cut the part out automatically - so it's going to be a hand-cut, using the age old method of scissors.)

The test fit perfectly. Now I can print out another one, glue it to whatever will back this up, cut and machine it out.  That will complete the rear bumper, or anything from the doors back except for the sound system.

It was around this time that I realized no one carries a bracket, no one has a bracket for sale from old cars, and the Assembly sheets from the factory show no bracket at all.  Really?  I went through all of that for nothing?

Yup.  Good exercise, though.  Now to install the plate.