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Oh - I like that idea.
I hadn't considered stitching to the existing vinyl. I was trying to figure out a way to melt them together - sewing is obvious now that you mention it. Thanks!
I decided my electric windows were too weak. Since I had the door panels off I did a quick test by applying 12V directly to the motor leads on the passenger window and it went up and down with authority. So decided to add relays to the window switches:
it was a pain in the *** to wire everything up, but it's done. The passenger window works well now, but the driver window is still a but sluggish??? It's definitely better, but not perfect... I'm going to test that motor with the 12v direct and see if maybe it's just a weak motor...
When I started the car to see how the windows worked with the car running I noticed that my shutter/coasting valve was sometimes activated while at idle??? If I revved the engine and then let off the gas, the valve would activate (loud sucking sound) but wouldn't always deactivate when the RPMs go down to around 1K RPM. It almost acted like it was "sticking" activated (although I don't actually think it's mechanical sticking this time)... I did some research and apparently the ECU controls the shutter vacuum solenoid, so I figured it may have been something feeding the ECU bad data. A bit more research led me to the Throttle Sensor. I didn't adjust that after the carb rebuild (again mostly thinking if I left it alone it would probably be correct from prior to the rebuild). But decided to go ahead and do the adjustment procedure from the Carb manual. Apparently the wire colors in the '83 are different than those described in the carb (81-85) manual, but I eventually figured out which connectors and wires were which. On testing, the throttle sensor was triggering the second lamp (from the test jig) out of time with the first lamp - so I went ahead and adjusted the throttle sensor per the manual - so now both lights turn on at the same time.
Now I'm noticing a very distinct hesitation/stumble as I go from idle up past 2K RPM. Right about at 2K the engine stumbles unless you get on it fairly aggressively. I'm pretty sure it wasn't doing this a week ago, but the only thing I've really done to the carb in that time is the throttle sensor adjustment. The loss of power is not being caused by the shutter valve activating... I took the car on a test drive to see of the problem was present on the road - and it is. If you don't 'push' it through 2K RPM fairly aggressively you can definitely feel the lag/loss of engine power.
Any thoughts on what that could be??? I understand there's a transition circuit in the carb that is supposed to handle the transition from below 2K to above 2K - so I would assume that would be a prime suspect. But the carb was recently rebuilt and everything got a good cleaning - also, this didn't seem to be an issue until just recently...
I put a meter on the driver window motor and it is drawing over 10 amps when opening/closing the window. For comparison, the passenger motor is pulling about 5 amps. This is with the motors being powered directly from a 12Volt source, so it excludes all of the car wiring except about a foot from the motors to the first connector (inside the door). I lubed the gears and the bottom track of the driver side window mechanism and there was no noticeable difference in the speed or amperage draw after the lubing. I think the motor is likely just getting very tired - will probably just leave it until it gets noticeably worse or fails...
Most of the time over the last two weeks was spent trying to track down the stumble at 2K. I ended buying an ultrasonic cleaner (which I *love*), pulling the carb and tearing in completely down again. I ran every part of the carb through the cleaner, blew them dry and made sure that every single air passage flowed air. The reassembly of the carb went without issue this time - and I'm certain all the gaskets were oriented correctly. When the carb went back on the car the same stumble was there - very annoying.
Pic of the ultrasonic cleaner - just for grins...
Yesterday I finally tracked down the issue. It was a leak in the #2 Anti-AfterBurn valve. In hindsight it's of course obvious, but I've been disconnecting that valve before pulling the carb and haven't paid any attention to it at all (other than to ensure the vac lines were re-hooked up when I put the carb back on. It turns out the fat line from the intake manifold to that valve was likely the culprit. I did "inspect" that line and it seemed in reasonable shape, I also have sprayed it with carb cleaner when looking for a leak - but I never completely pulled it off. When I did, both ends of it were covered (on the inside) with a talc-like powder. It's unlikely either end was making a vacuum tight seal on their respective nipples. To test I capped the nipple on the manifold and plugged the two small vac lines going to the valve - the stumble disappeared. I gave the valve and the lines a nice warm bath in the ultrasonic cleaner. That seemed to rejuvenate the fat vac tubes quite a bit (not only cleaned them, but softened and tightened them up quite a bit also. Today I put the whole assembly back on the car and the stumble is still gone. Yay!
So now the engine seems to be running well from idle all the way through to 6500 RPM (and probably beyond, but I didn't temp fate). I took it on a test drive and everything seemed to perform well.
Over the last couple of weeks I've also performed a pressure (well vacuum) test on the heater core (from the fittings that stick through the firewall) and it didn't perform well -- wouldn't hold a vacuum. I have a replacement assembly which I also tested and that held the vacuum just fine (overnight). I'm still hoping the problem is somewhere in the lines/valves going to the core, instead of with the core itself, but I suspect it will end up being the same amount of work either way...
I did get a nice surprise this afternoon - I decided to go ahead and give the AC a try and to my utter amazement - it began blowing cold air. I never would have expected that.
Of course, to balance karma out a bit, I also did some quick testing of the interior lights (map light and dome light) - neither worked. But I swear I've tried both out when I started working on the car and both worked fine then. Now the dome light seems dead (which could just be a dead bulb), but the map lights caused the buzzer (like the door open buzzer) to sound??? I didn't dig into anything, but the symptoms sure seem weird!
Over the last couple of weeks I've been cleaning up some of the bits and pieces that haven't been touched yet, like the:
* Cruise Control
* Wiper fluid reservoir
* Sub-Zero Assist (which I've decided to not reinstall)
* Hot-Start Assist (also decided to not reinstall)
* Charcoal canister
* Relays on driver fender
Mostly just pulling the various components, cleaning and inspecting them before reassembly.
When I went to replace the wiper fluid hose I discovered this under the cowl:
Somehow this mouse-house had escaped my notice up to this point! It's now been cleaned out and scrubbed down...
I decided to go ahead and give zinc plating a try. There are lots are previously plated parts where the plating has pretty much reached the end of its useful life. They just don't clean up very well and I think a fresh plating will do them good. I've been following FrankenRex's progress closely and he's inspired me to go ahead and give it a shot.
I'm using the recipe for the plating solution from this site: Zinc Plating with Common Materials
Here's my setup as I began mixing the electrolyte:
I ended up only mixing a half batch, which filled the plastic tubs I got from the dollar store.
I'm still waiting on the chromate solution I ordered from Caswell to ship, so today was mostly just practice with the plating steps.
I did the charcoal canister bracket and bolts. The bracket started with some fairly rusted areas (but I forgot to take a pic of it). I blasted it, then dipped it in the muriatic acid:
After 10 mins in the plating bath @350mA it came out looking like this:
After a little brushing with a brass brush it looked like this:
(hard to tell much difference?) But a second pass in the plating bath for close to 20 minutes @500mA, then hit with a brass brush again followed by a quick hit with Mothers polish and it came out like this:
Not a mirror finish, but good enough to catch a reflection.
The bolts I didn't even bother cleaning first, just straight into the acid bath, rinse and then into the plating bath (they were in with the bracket for its second pass).
Before:
And after - with just a brass brushing:
My overall impression is that this is even easier than it seems and I can't wait for the chromate solutions to arrive...
I guess until that happens I'm just going to monitor how these parts age. I've read that non-chromated zinc plated parts can become grey and gummy over time, so it'll be interesting to see if that is the case or whether the simply plated parts hold up...
The Caswell Chromating solution finally arrived and I played around with that some... One of the relay covers I plated chromated well, the other not so much:
After stripping it and replating it, it turned out better. Still not perfect, but certainly close enough:
I also tried chromating directly after pulling from the plating bath (without any scrubbing with the brash brush). The results are definitely not as 'shiny' as the the polished parts, but decent enough for general hardware:
All in all, I'm still quite pleased with the overall process - pretty easy, could be quicker, but doesn't take *that* long...
I've put all the bits I've been cleaning back under the hood. Before reinstalling the hood latch I added a 'safety' cable to allow me to open the latch from under the car in case the original cable ever fails on me:
When I had everything back together I was moving the car and noticed I think my alternator has failed on me... Since I was playing with the relays I was thinking that maybe I did something with those that made it look like the alternator wasn't working, but after a bit of troubleshooting I'm pretty convinced the alternator has simply failed on me... sigh...
I've ordered a replacement from RockAuto -- from info I found in the archives I decided to go with one from an '86 instead of the original...
Nice work on your plating!!! I really need to get involved in this on several of my cars. Ohio is not kind to the plating and I think it would be enjoyable to spend a day restoring parts with new plating. Will make a world of difference under the hood for sure!
Took a brief hiatus... It started with the fluorescent light right over the car going out. I decided to replace all the fluorescents with LED bulbs, this required me to rewire all 8 fixtures, which required getting a large step ladder under each, which led to me realizing all my floor space was taken up with piles of stuff, which led to me deciding to clean and reorganize the entire shop... Three weeks later and I'm finally done!
Back to the car... I've decided to take the plunge and try to get to the heater core. I have a replacement that vacuum tests as good, but getting to it to replace it apparently involves pulling out the dash. I've been dreading this step, but I've started:
With the instrument cluster out, I also want to address the problem with my Tach. When it's the slightest bit cool outside the tach doesn't want to "wake up" (and work) until the car is completely warmed up. There is some movement of the needle, but it's like it's stuck in honey - it moves really, really slowly... It was doing this in the late '80s, so it's not a new phenomenon. I was hoping I'd find a bad capacitor on the cluster panel, but I'm currently not seeing any electrical components at all. (I suppose they could be on the 'front' facing side of the circuit board, but I would expect to see some legs sticking through to the back... So - before I destroy this thing by taking it apart too far, figured I'd ask if anyone has any ideas on what to check? My completely random guess is that it may have something to do with this thing hanging off the back of the panel (dead center in the pic):
It is shown in the FSM, but is not identified. Any know what that is, and if it could be the culprit?
Took a brief hiatus... It started with the fluorescent light right over the car going out. I decided to replace all the fluorescents with LED bulbs, this required me to rewire all 8 fixtures, which required getting a large step ladder under each, which led to me realizing all my floor space was taken up with piles of stuff, which led to me deciding to clean and reorganize the entire shop... Three weeks later and I'm finally done!
Back to the car... I've decided to take the plunge and try to get to the heater core. I have a replacement that vacuum tests as good, but getting to it to replace it apparently involves pulling out the dash. I've been dreading this step, but I've started:
With the instrument cluster out, I also want to address the problem with my Tach. When it's the slightest bit cool outside the tach doesn't want to "wake up" (and work) until the car is completely warmed up. There is some movement of the needle, but it's like it's stuck in honey - it moves really, really slowly... It was doing this in the late '80s, so it's not a new phenomenon. I was hoping I'd find a bad capacitor on the cluster panel, but I'm currently not seeing any electrical components at all. (I suppose they could be on the 'front' facing side of the circuit board, but I would expect to see some legs sticking through to the back... So - before I destroy this thing by taking it apart too far, figured I'd ask if anyone has any ideas on what to check? My completely random guess is that it may have something to do with this thing hanging off the back of the panel (dead center in the pic):
It is shown in the FSM, but is not identified. Any know what that is, and if it could be the culprit?
If I'm not mistaken that silver box in the back is the redline buzzer.....not sure if it will contribute to the symptoms of the needle.....
Ah, that would make sense. Thanks for the info!
My google searching is not helping much with details on the tach, so I think I'm going to dig into it very carefully tomorrow...
I pulled the tach out of the cluster today - it turns out there is a circuit board on the tach itself:
However, the two electrolytic caps on that board look to be in good shape. I decided to hook an adjustable power supply directly up to the meter and found that needle did have a tendency to stick (around 1000 RPM). This led me to the hypothesis that the meter movement itself was to blame for the stickiness I experienced. I carefully removed the meter (which involved pulling the needle off as well) and after I was fairly certain there wasn't anything that was going to be eaten by brake cleaner I gave it a gentle spraying. Followed this up with some very gentle compressed air and then retested the movement. Retesting it the stickiness appears to be gone - maybe yay?
Everything is cleaned and back together, but I won't be able to test it in the car until I complete pulling the dash and addressing the heater core...
Yeah, but I didn't feel like walking back to the house to dig out my can of Deoxit The actual meter movement is basically a (magneto-) mechanical assembly anyway, so I figured it would be safe (once I determined the plastic bits wouldn't be melting on me).
Anyway, more progress today - I've managed to get the dash stripped down to just the frame and the cap. Hopefully I'll be able to wrangle some help to try to pull it in the next couple of days. I took a ton of pics, but imgur is being an *** right now and ignoring my uploads so nothing to share yet.
No big surprises, other than I did have to take the combination switch off the steering column to get the dash out of the car:
So now the whole reason for pulling the dash, the heater box, is sitting there right in front of me:
Two bolts (maybe nuts) mount the top of it to the frame, but there is a third near where the heater pipes pass through the firewall. And that appears to be positioned directly behind the Air Conditioning evaporator coil?
Can this be the case, do I really have to remove the A/C to pull the heater box? I'm going to do some googling right now, but if anyone has any tricks for getting the heater out without disturbing the A/C, please do tell...
Ok, progress to report... I have finally got the heater box removed from the car:
But, as you may notice - I did have to remove the A/C evaporator coil to finally get the heater out. So, before this is all over I'm going to have to go down the "upgrade to R-152A" path as well...
Here's a shot of the offending heater core:
I already have a second heater box that has a core which tests good (can hold a vacuum), but my box actually appears to be a somewhat better overall condition. So my plan is to refurbish the original box and transplant the other core during the cleaning process. I haven't had a chance to give the foam in the box a good review yet, so not yet certain whether that will need replacing as well - I'll make that call once I start tearing into the box.
Somehow I actually missed those two threads - thanks for linking them! I did find several others which made the process pretty painless though...
Everything is apart and most of it is cleaned up at this point. I'm waiting on some foam to be delivered before I can refoam the flaps.
One of my original flaps had quite a bit of rust on it:
I'm sure I could clean it up with a trip through the blast cabinet, but the ones from the donor box were in decent condition, so I focused my attention on getting the residue of the foam off them:
That pic above is a little misleading -- the other half of the harness came out with the dash.
Although It is nice that the two parts disconnect from each other so you can pull out the dash then deal with its harness, instead of having to deal with it while upside down...
Oh I know what it is like to look at the dashbord 'head over feet'
In any case, I wish it was so nice and clean! Eventually all went back together anyway.
Oh, btw, this thread is very instructive, thanks
Heater and blower boxes are done with their refurb - basically just a good cleaning and replacement of the deteriorating foam. now have begun the process of putting it all back together...
And where it currently stands:
I do have one issue though... There's a four pin (male) connector on the passenger end of the dash harness that does not appear to have any corresponding plug. I've gone through the wiring diagrams and cannot find any reference to it??? This is the connector I'm talking about:
Kind of looks like power to the fan, G-01 on page G of wiring diagram, but that seems like it would be too obvious. I haven't had any of that stuff for quite a while, so just a guess.
I'm pretty sure that's not it -- I have the connector to the fan plugged in already. I was trying to track it down by wire color. I don't recall the colors at the moment, but it seemed like it was quite similar to the harness that feeds the door, but I can follow that harness right out of the door, and all connectors on it are populated as well...
Honestly, it's in a fairly accessible place, so I've just let it hang loose for the moment. I did spend all day putting the center console in - probably buttoned it up and then had to go back in 3 times due to finding one more connector that I couldn't get to the matching plug on... what a pain in the ***.
For example - here it looks all nice and buttoned up -
but notice that wire hanging down to the right - yep refrigerant pressure signal that needs to plug into the a/c controls at the top. The whole thing needed to come apart to get me enough room to plug the damn thing in...
Ah, also noticed I have a pic of another (apparently) unused connector:
This one is down near the balance control and switches at the bottom of the center console... I haven't tried finding that one in the diagrams yet though - but there is obviously nothing it can plug into, I'm assuming for now it's probably for a different radio option...
After spending far too much time upside down under the dash the interior is back together:
Everything tests out and works - except the tach is still sluggish and sticky Apparently I should have replaced all the caps on the circuit board while I had it out... sigh...
I checked the wire colors on the rogue connector under the passenger dash (LY, LG, LR, LW) and from what I can tell in the wiring diagrams, that would appear to be Audio connector J11. But it's not located in the proper place. At this point I'm convinced it must be an extra for some other audio option. The stereo works without anything plugged into the connector, so I'm calling it done.
I found a pic from my tear down that shows the extra connector under the center console as unused as well, so probably for some option I don't have (probably also another stereo setup).
I mentioned in the last post that after I got everything back together the tach still had its 'sticky' problem. So I decided that I am going to kill that problem dead, no matter how long it takes...
I pulled the instrument cluster back out and pulled the tach. Then I built a small testbed for driving the tach outside the car. I used an Arduino to read a pot that allows me to dial-in desired RPM values, then I generate an output signal which drives a transistor to switch a 12V signal on and off at a frequency corresponding to the desired RPM. The schematic is very simple:
And here is the driver plugged into an Arduino Uno:
This is the test setup with the driver hooked up to the tach board (disconnected from the tach itself) and the tach:
Once I got the arduino code running correctly turning the pot results in a nice smooth sweep of the tach needle... Hmm, that's not "good" - I did all this because I figured the tach board was flaky???
However, sometimes the tach works fine (in the car) and sometimes it gets "sticky", so I'm still thinking it's something to do with the tach itself. So I go looking for a schema of the 1st gen tach board -- this apparently does not exist. I found lots of good info on the FD tach, hoping it would apply - but sadly it does not... In the end I just bit the bullet and reverse engineered the schematic from the board itself:
Then I went searching for any info on IC1 the T2295A chip... There is basically almost no info on this chip available. There are suggestions that is "sounds" like a frequency to voltage converter - which would make perfect sense for this application - but the only 'concrete' info I could find was this reference schematic for use of this chip in a ...wait for it... tachometer - ok, that sounds promising:
The detail oriented will notice that the Rx7 tach schema and this reference schema are almost identical. The only differences are two legs of the trim pot being tied together on ours, and a few of the components have different values (C4, R3, R5 and the trim pot in particular), also C6 is missing in our version. I triple checked the differences against my board, so I'm pretty confident the schema I posted above is accurate.
Unfortunately, this doesn't tell me whole lot, other than IC1 is where the magic happens... I stuck my scope on the input signal (output from the tach driver I made) and the signal driving the meter:
Yellow trace is the input signal, blue trace the pin driving the meter. That output (blue) signal does not look like what I was expecting. I have no idea whether my expectations are correct or not, but I was expecting to see a stable voltage being fed to the meter (that varied with the frequency of the input signal), not a pass-through of the input signal, just 'deformed' a bit by the caps...
I happened to have the proper caps to replace C2 and C4 (the only electrolytics on the board) so I went ahead and removed the originals and replaced them with new. The result was exactly the same output signal. The old caps looked in decent condition (did not look like they had blown their guts out) and in fact, both read about 39uF on a tester I have - they are supposed to be 47uF, but 39 is within 20%, so probably within spec.
So, at this point I'm really not certain whether the tach itself is working correctly or not. It seems to work ok on the bench, but the output signal is not what I was expecting to see. I did find a place on ebay selling the T2295A chip, it's only $7 so I decided to go ahead and get one. Unfortunately is wont get here until around Christmas, so there will be no instant gratification on this one. What I'm probably going to do is put the tach and cluster back into the car and hook the scope up to the signal driving the tack to see if I can see it flaking out when the tach is acting up -- probably should have done that first, but the symptoms just screamed to me that it was a problem with the tach itself...
08-10-21, 10:11 AM
The actual meter movement is basically a (magneto-) mechanical assembly anyway, so I figured it would be safe (once I determined the plastic bits wouldn't be melting on me). 
Apparently I should have replaced all the caps on the circuit board while I had it out... sigh...
