So I mentioned in the previous post that I’ve got my HMV freeway to the point where I’ve been able to drive it to work on a regular basis. This is a bunch of the stuff I’ve done, in no particular order.
Bodywork
I spent a while sanding back the primer exposed when the paint came off, mostly because I could see a fair bit of filler, and was curious what it was hiding. Surprisingly, it appears that I believe this Freeway has been laid on it’s side in the past:
The right-hand side has a bunch of fairly deep scratches, though none substantial enough to be of any concern to the body’s structure. This is actually fairly encouraging, since it means the rebuild isn’t hiding a major problem. It also means this thing was robust enough to slide on it’s side a fair bit without just disentegrating, which says positive things about its (likely marginal) crash safety.
I also painted the interior of the lower body:
That came out well enough that I wound up just going “YOLO” and using the same paint (rustoleum) to do a roll-on paint-job for the top:
I’m less happy with this. It looks fine at 10 feet, but it’s not good up close. At the moment I’m living with it just because I want to drive the thing, but I definitely want to sand it off and have the thing properly painted in the future.
I also had to revisit a bunch of the bodywork I’ve done. The fuel-filler recess is just a bit located too low, causing the fuel cap neck and the tank neck to actually hit each other. It also needs to be moved rearward about a half-inch. So this means I needed to cut all the work I’d done out, and redo it.
I also decided to experiment with vacuum bagging. I did a test piece, and it came out really well. I’m using a UV-catalyzed polyester resin here, and it is super convenient. I should have been using this the whole time!
I was able to push the glass around in the bag pretty well, and it set nicely once I put it out in the sun.
I then tried to do the real thing, and that didn’t go as well. I think I’ve mentioned before I’m working in my carport, because I do not have a garage. This causes issues here, because while I am in the shade, there was enough UV exposure there that the resin started gelling before I had finished the bagging, so the glass didn’t properly get pulled into the corner around the mould. I tried to throw everything together as fast as I could, but I still wound up with a poor result. Sanding it back to remove the sharp corners on the exterior face went all the way wound up going completely thru the body in a few places, so I re-prepped and added even more glass on the interior of the body to hold everything exactly where it needs to go. I also used short-strand reinforced bondo to reconstruct the filler neck shape on the exterior.
It needs more work (sanding the interior of a conical profile is not easy), but I threw some primer on it so I can at least drive the thing. Really, the whole nose needs some more care.
Engine Maintenance
The engine in my Freeway has always been somewhat hard-starting. I assumed this was just because the engine was tired and worn out, but I set out to measure that. This means I needed to remove the head, and measure the bore.
For this engine, this is way way more work then it should take. This is an overhead valve engine, and pretty obviously Tecumseh engineered it by just hacking pushrods + overhead values into an existing engine design. The valves are located in a valve box that is just bolted to the top of the engine, obscuring some of the head bolts.
This means you have to remove the valve box to remove the head. To remove the valve box, you have to remove the valve springs. To remove the valve springs, you have to remove the rocker arms.
This is, to put it lightly, extremely annoying. It took me most of the afternoon to deal with all the annoying steps, figure out a janky valve spring compressor to let me remove the valve spring keepers, etc…
Once things were disassembled, I was able to use some snap gauges to determine the cylinder bore is about 0.004-0.005 oversize at the bottom. I also found a lot of carbon deposits that I cleaned out. The valves looked fine, though the exhaust valve was a bit loose in it’s guide. The cylinder was also pretty glazed, so it definitely needs work.
I then reversed the process, getting everything back together, torqueing things, etc.. I had it fully reassembled, put oil in the engine, etc..
…
And it wouldn’t start.
Considering I was pushing to get this together to go to a project vehicle meet at work, this was annoying to say the least.
After some debugging (and finding I had missed the engine-stop connection), I had spark, but the hall effect sensor I had added to give me a tachometer output was causing it to spark at the wrong time. That was easy enough to fix (remove the magnet, which was several inches from the CDI ignition pickup), but it would still barely turn over.
At this point, I suspected the starter, and amazon had a replacement for $50, so I ordered one in hope that would be the issue.
Aaaaand, it turns out the starter has probably been dying for longer then I had the Freeway. It ha always been kind of lound and made grinding noises, but I assumed this was just crappy lawn-mower engine parts. It turns out the starter was just dying the whole time.
It starts so much easier now, you don’t need to spend several minutes fiddling with the choke, and it just sounds like a motor now, not dying gears.
Out of curiosity, I disassembled the old starter:
1 1/2 of the brushes appear to be dead. Specifically, the spring that provides force to push them against the commutator has completely lost their tension. I’m guessing that just the few bumps from handling the engine out of the chassis knocked the brushes back enough that they finally completely lost contact with the commutator.
My assumption was it overheated at some point, and the springs got hot enough that they deformed and annealed enough to lose their springyness. One of the carbon brushes was stuck in it’s brass guide, and the two failed brush guides have pretty obvious temperature related discolouration.
……
On the other hand, Tecumseh made both 0.010” and 0.020 oversize pistons for this engine, and a 0.010” oversize new-old-stock piston with rings and wrist-pin on ebay was $50, so I now have new rings and a oversize piston to put in the engine. I just need to find a local engine machine shop that will humor my bizarre engine.
