I had the Dart at a car show at about the time the tach stopped working. On the way home, the temperature started creeping up (unfortunately the OE gauge has no numbers), and so did the idle speed. Unfortunately with a dead tach I'm not sure what it crept up to, but probably at least 1800 and was likely at least partly driving the overheating. It didn't boil over until shutting down, though. I checked a few possible causes of the idle speed and re-adjusted the throttle stop.
Took it on a short test drive today. I shut it down when temperature reached around 205 degrees - that does look fairly normal on the gauge but I have a hard time pinning down exactly what normal should be. It's a bit above thermostat temperature. (And the fact that it's a fresh rebuild probably makes it a little hotter.) However, there was a bit of trouble when I shut it down. I was sitting in my carport reviewing the data logs as the engine cooled when this happened.
Probably had the clamp in not quite the right spot or not as tight as it should - or maybe the hot run home loosened it.
Speaking of boiling over, the coolant overflow tank is empty. Looks like it's sprung a leak. So, next steps will need to be a new coolant, new overflow tank, and an oil change. I'd also like to do something about the gas gauge, which seems to be hitting full low when I've got half a tank.
On the bright side, the AFR numbers from my data log looked pretty good.
Boiling over after shutdown suggests that the coolant was already boiling in the cylinder head and when you shut it down, the lack of water pump pressure allowed the steam to expand.
This is where stuff like Evans is supposed to be great, because it doesn't boil in the head nearly as easily. I never really liked the worse heat transfer properties though. Give and take.
Thanks, I had seen a few teaser pics of that build but not the final result.
I think the boil-over is from a lack of circulation allowing local hot spots to keep getting hotter rather than pressure. This isn't the first car I have owned where the coolant temperature rises after the engine stops.
Since the plastic overflow tank appears to be leaking, I ordered a cheap generic overflow tank off Amazon. Got it installed using an existing hole in the radiator support, but I needed to drill a hole in the lid as a normal overflow tank shouldn't be pressure tight. The seller also included the wrong size hose clips and a roll of Teflon tape for no discernable purpose.
I couldn't resist leaving a somewhat snarky review.
Thought of your car when I saw this in Ocean City MD today!
Nice find, I especially like how they've managed to combine the gasser beer keg fuel tank look and make an air to water intercooler out of it.
Meanwhile, a related project has been siphoning off my Dart modding time, although the two projects are about to come together. I'd been hearing complaints about the quality of aftermarket replacements for Mopar voltage regulators and ignition modules. So I recently did a teardown on a replacement for a Chrysler voltage regulator. I concluded I could build a better voltage regulator on my kitchen table.
And here is the work in progress on my kitchen table.
Still waiting on a few parts to arrive.
The engine computer won't control a Chrysler alternator?
Pete. (l33t FS) said:
The engine computer won't control a Chrysler alternator?
Yes, the MS3 could control the alternator if I wanted to.
But there are a lot of other Mopar fans who haven't switched to EFI who could use a regulator that wasn't stuffed full of sand with critical parts deleted.
MadScientistMatt said:
Pete. (l33t FS) said:
The engine computer won't control a Chrysler alternator?
Yes, the MS3 could control the alternator if I wanted to.
But there are a lot of other Mopar fans who haven't switched to EFI who could use a regulator that wasn't stuffed full of sand with critical parts deleted.
On a real computer now instead of mobile, I can see the markings on the circuit board. Cool stuff!
I have many questions about low volume circuit boards, now.
Pete. (l33t FS) said:
I have many questions about low volume circuit boards, now.
Short run boards are a lot easier to do than they were ten years ago. Designing the board is a similar process. Almost all the software out there has something I hate about it, but I used Kicad for this one. There are a few bugs and some weird interface quirks, but every PCB design program out there seems to have an interface that made sense to the programmer but not a new user.
The real step up has been shops that can do an instant online quote and don't have setup fees. I used OSH Park for these. There are several others out there. Hackaday recently published a roundup.
I'll put together a write up on the aftermarket regulator for this board soon, but in the meantime you can view this thread on slantsix.org.
Took it for a short drive around the neighborhood, about four or five miles total, low speed. Temperature gauge started creeping up a little toward the end of the drive. Unfortunately I didn't have the computer data logging to get hard numbers. Caught a faint whiff of coolant but not sure if it actually leaked out or was spilled coolant that had heated up enough to smell. I'll see what the coolant level is when it cools down.
Edit: Well, at least the coolant isn't going anywhere.
I'm wondering if I will get better cooling at low speed if I remove the shroud and zip tie the fans to the radiator. I had wanted to avoid that to reduce stress on the radiator, but better the radiator than the engine...
So I took the front end apart to use radiator zip ties instead of the shroud to hold the fans.
Took it for a short test drive today, temperatures didn't show any of the "creeping up" behavior in a log. It was also a bit cold (and a chance to make some improvements to cold start tuning). I'll take it for a longer test drive soon. So far it looks like it's quite possible the shroud was either positioning the fans badly or hurting low-speed airflow.
Also got a shot of how you can just barely see there's something a bit suspicious behind the stock looking grill - if you shine a light on it.
Testing a few parts on the car. First trying what was supposed to be a finished voltage regulator, except potting and heat sink. It passed a bench test.
Unfortunately the battery voltage pegged at 19 volts.
Surprisingly, it still passes a bench test, so at least nothing went up in flames. Which is an improvement over previous tests. Maybe I should get rig up some sort of alternator test bench so I don't subject my car to overcharging.
One of my neighbor's friends happened to have a '66 Dart instrument cluster for sale. Before trying a full cluster switch, I connected the speedo cable to the cluster.
The good news: It's reading a speed.
The bad news: The car wasn't moving when I took that picture.
Took the cluster apart, and I don't think it is supposed to look like that.
It looks like I've found the issue. There is a plastic rivet that holds a sheet metal clip to hold the spring in place. Unfortunately, the rivet is broken and the clip spins freely. I'm wondering if I can salvage this myself without sending it off for repairs. Stay tuned...
Not much luck finding speedometer service parts, and repair services cost a lot. Two possibilities have turned up:
1. Gun drill a nut and bolt to replace the rivet.
2. Start with this...
If you go with option 2 you need some way to generate a speed signal as you know...
I used one of these and got the ~$20 external antenna to go with it. I mounted the antenna at the top of the drivers' windshield corner. In my situation, the Dakota gps unit drives a variable speed motor to run the O.E. speedometer and odometer in my '64 dart. It works regardless of transmission/tire size/rear end ratio swaps and is always dead nuts on accurate after initial setup and calibration.. those parts are probably more costly than sending your unit to a speedometer shop.
I would be willing to bet that your '66 guts are similar to the '67-71 A body mopar guts too. Some core buying could yield a bunch of usable parts.
MadScientistMatt said:
1. Gun drill a nut and bolt to replace the rivet.
You probably know already, but I only recently found out that it's a lot easier to center a hole down a bolt if you hold the drill still and spin the bolt. Chuck the bolt up in a drill press and clamp your drill bit in a drill press vise. Might not work every time but it's worked for me.
As I don't have a drill press, I am first trying yet another spare cluster I found on slantsix.org. If that doesn't work, it appears there's a VSS that will fit the stock cable.
I've been up to another project - trying to create replacement voltage regulators. The current batch had a bit of a setback when a tube of something sold as potting compound was clearly meant to be a caulk or sealanat instead. But since my voltage regulator is mounted in the trunk anyway, not the biggest setback for my own testing.
Today I ran this for about 20 minutes with no issues happening. Next step is to make a batch of more production-ready regulators.
I know, a lot of the little sorting everything out issues won't be as exciting as taking the engine apart and porting everything that has ports (including the oil gallery and water pump). But it's the little things you need to get a project across the goal line.
One of the members of slantsix.org came through with a (finally!) working speedometer. Time to get the cluster out. First I loosen the center section of the dash trim. (Now that I have a 3D printer, maybe I should put a bezel on this so I don't have to look at cut up plastic...)
Four screws, and you can slide the cluster forward and start unplugging things.
It's out.
Next steps will be to take it apart to swap out speedometers.
The really hard part is going to be getting the fuel gauge to read right with the cheap repop sending unit, which is way off...
That is not hard at all! Get yourself a metermatch unit from technoversions.
Got the speedometer swapped out, and I have a working speedometer. Yeah! Unfortunately the green lenses over the turn signal indicators fell down so I now have one bare bulb and one knife edged thin slit. Boo. Will deal with that later. I even tried to match the replacement cluster's odometer reading to my original.
The Metrimatch looks interesting, but I have a lot of I/O on the MS3 that isn't in use...
Some cluster disassembly pics:
This has been sitting in my shed for too long. Narrowed C-body 8 3/4" rear axle with 3.55:1 gears, Sure-Grip, Moser axle shafts, and 11" drums.
It's too heavy for Kelly and me to move safely, probably a bit north of 200 lbs. But I was able to get some help from a fellow Mopar nut yesterday - thanks Bobby! After a morning of wrenching, here is where things stand.
Now to track down a couple key swap items - shorter driveshaft, spring plates, U-bolts, and a few other sundries. You may also see a few interesting junkyard parts make an appearance as long as I have things apart back there...
