tons of info needs to be extracted from this thread

[oldman3]

Jim,glad you are enjoying the truck and having a good time, keep us posted....Jim

[bollybib]

Originally Posted by oldman3

Jim,glad you are enjoying the truck and having a good time, keep us posted....Jim

Thanks, Jim. It is a lot of fun, that's for sure. This is the first long highway journey I've taken in it and I got more than 13 mpg - o wow !


Here's a fun pic I took at El Porto: Find Jim's '69 Custom/20 (pretty easy to pick out even at this distance).


And another from behind.


Right now I'm finding all sorts of missing, broken or disconnected stuff as I go through my heater controls. I figured now is the time to get it in shape before the winter chill sets in. I also ordered a bunch of stuff from Classic Parts recently so that should keep me busy, too. Nice thing is, now I'm at the point where I can fix or install this stuff with little or no down time.

Pax.

[oldblue1968chevy]

no down time mods are the BEST

[bollybib]

Originally Posted by oldblue1968chevy

no down time mods are the BEST

[oldblue1968chevy]

any awesome updates

[bollybib]

Originally Posted by oldblue1968chevy

any awesome updates

haha.,,.,.working on a couple now

[bollybib]

HVAC (1 OF 6)

I got into this system because the heater was fubab’ed and I wanted to get it working before I really needed the warmth. I found a lot of missing, broken, disconnected, worn out, dirty, and deteriorated parts during this quest for heat. My goal was to get the whole system functioning properly with the exception of the AC compressor loop. I don’t really need or want AC and the compressor is missing anyway. So here is a list of what I had to do to the heating, ventilating, and air conditioning (HVAC) system to get it functional and me warm.

This schematic in the Service Manual gives
a good overall picture of the HVAC system.

Inside the Cab

PROBLEM 1: The passenger side AC diverter ball housing has two broken retaining tabs so the ball flops around in the hole.
SOLUTION: I wanted to reuse the existing housing because it has factory paint. I installed a screw near one tab and epoxied near the other (no easy way to drill in this location). The ball now sits firmly between the felt pads.



PROBLEM 2: The uppermost lever in the Control Unit (CU) is broken.
SOLUTION: I got a new lever, removed and disassembled the CU, installed the new lever, cleaned and lubed as necessary, and reinstalled the CU. The CU is a busy little mechanism what with two lamps, the fan speed connector, three Bowden cables, three vacuum lines, and a bracket connected to it, all in a very confined space. It’s a good idea to mark everything and take a lot of pics so you know where stuff goes when you hook it back up.

[bollybib]

HVAC (2 OF 6)

I found this member’s thread very useful when doing this work. - - - - > 67ChevyRedneck, Rebuild you A/C controller http://67-72chevytrucks.com/vboard/s...d.php?t=245558



CU removed……...............................………......................……….Broken lever



Broken lever removed…….......................................................Back together again


PROBLEM 3: One illumination lamp in the CU is burned out.
SOLUTION: I installed two new 1895 lamps.

PROBLEM 4: The diverter box outlets door is broken at the hinge.
SOLUTION: Over time, the plastic will fatigue and break near the hinge rod and the door becomes mechanically disconnected from the rod. The door usually ends up being stuck in the down position so that air is always diverted into the AC ducts and never to the heater ducts (which is how I discovered the problem).

There are many threads posted in here that discuss this issue and offer repair advice. I figured I’d try to make the repair since no one sells just the door and the whole box runs $90 or so.

[bollybib]

HVAC (3 OF 6)


All sorts of little plastic pieces fell out


I found this adhesive at the hardware store that looked like it would work. I ended up using two.



I notched the hinge rod so the epoxy would have a good grip when the rod was rotated.



I cut away one side of the rubber only as wide as my strip of fiberglass. Then I inserted a band of fiberglass cloth so that it would wrap around the hinge rod and lay flat on each side of the door. I have stuff on hand to fix my surfboards, so I already had this fiberglass.

[bollybib]

HVAC (4 OF 6)

I first cleaned all the epoxy contact areas on the door with acetone. I applied a small amount of synthetic grease to the two rubber/duct contact points and set the door into place in the duct. I inserted the hinge rod ensuring that it passed through the fiberglass cloth loop, and then applied the epoxy in four steps.
1. I filled the gaps at the corners where the plastic had disintegrated with a mix of epoxy and fiberglass.
2. I applied a generous amount of epoxy into the loop and onto the hinge rod and then snugged up the loop.
3. I applied epoxy with a small squeegee to saturate the cloth against the flat side of the door.
4. I applied epoxy with a small squeegee to saturate the cloth against the cage side of the door.

I trimmed the fiberglass cloth as best I could after the epoxy set up but before it hardened.




After the epoxy cured, I went at it with a Dremel tool using a diamond grinding bit. I dressed up the excess epoxy and fiberglass so the assembly moved freely in the duct.

Hard to say how well this repair will hold up but it works good now and for a lot less money than a whole new box at $90.


PROBLEM 5: The S-shaped duct is cracked at one corner and is missing part of the flange at one attaching hole.
SOLUTION: I repaired the damage with fiberglass and epoxy. A new duct would run around $25.


PROBLEM 6: One hole in the diverter box is stripped and won’t hold a screw.
SOLUTION: I filled the hole with epoxy and drilled it to size. Now it will hold a screw.


PROBLEM 7: The outlets cable and the heater/defroster cable are kinked.
SOLUTION: I straightened out the kinks. The cables’ resistance to movement was noticeably less afterwards.


PROBLEM 8: The floor outlet/defroster door is hard to move.
SOLUTION: I cleaned the interior of this metal duct and lubricated the metal-to-metal contact points. The door has a spring loaded detent on one side and a small sliding shoe on the other. I straightened the control cable as described in Problem 7.


PROBLEM 9: The air ducts are brittle and break easily.
SOLUTION: I repaired a torn defroster duct with fiberglass and Black RTV. The driver side AC duct disintegrated at both ends, so I bought a new set of four AC ducts. I’ll install the two lower ducts that go to the ball vents and save the uppers for another time.

Engine Compartment and Cowl

PROBLEM 10: There is a lot of debris around the cowl vent door
SOLUTION: I removed the cowl and cleaned the exposed areas. I removed the door and washed it with soap and water, then reinstalled it.


PROBLEM 11: The return spring on the cowl vent door is broken.
SOLUTION: I installed a new spring. I couldn’t find one exactly like the orignal, so I made one up with a shorter spring of about the same K and used chain link at both ends to make up the difference.

[bollybib]

HVAC (5 OF 6)

PROBLEM 12: The blower groans loudly at all speeds.
SOLUTION: There are many threads posted in here that offer advice on how to remove the blower, but pics are rare.

Access to and removal of the blower is constrained by the hood hinge. I chose to remove the two rear bolts on the fender side of the hood hinge and then rotate the hinge and hood out of the way on the loosened forward bolt. I had to first unfasten the blower so I could loosen the upper hinge bolt. It’s a good idea to mark the original location of the hinge.





The blower has to be rotated a few times to get it past the hinge (I was reminded of a few mechanical puzzles I’ve played with).

[bollybib]

HVAC (6 OF 6)
Once I had the old blower out, I found the driveshaft was real wobbly so that’s what was causing all the racket I heard.

Then I installed a new blower motor and set the hinge back in place. Even with the difficult access, the job only takes a couple of hours or so.




PROBLEM 13: The two barbs on the vacuum reservoir have nothing connected to them.
SOLUTION: I installed a new vacuum supply hose from the reservoir to a spare port on an existing intake manifold tree. I connected a loose hose I found that supplies vacuum to the CU in the cab.


This little schematic in the Service Manual
is quite useful for checking out the vacuum controls.


PROBLEM 14: There are two unconnected vacuum hoses near the heater/AC housing.
SOLUTION: I connected one of them to the vacuum reservoir (Problem 13). I connected the other one to the water valve. I had to lengthen this hose with a new piece of hose and a connector because it wouldn’t reach.


PROBLEM 15: The water valve is missing
SOLUTION: I obtained and installed a new water valve

I left a lot of excess vacuum line coiled up for now.

PROBLEM 16: There is no port available on the intake manifold to connect the heater hose.
SOLUTION: I changed the location of the temperature sending unit from the intake manifold to the cylinder head (see TEMPERATURE SENDER REVISITED, below). I then installed a pipe nipple and connected the heater hose where the temperature sender used to be. I had to reroute the fuel line a little.




PROBLEM 17: I can’t seem to stop buying parts and fixing stuff on this truck.
SOLUTION: I’ll make everything perfect so it will never need another thing.


It took me a while to get there, but once everything was fixed and back in place and I set it to heat … Voila ! I got HEAT ! (I could say this is a very cool thing to have but that would be contradictory).

Brass el fitting…….....……….………$....8.69
Heater hose……………….......………..…10.63
Water valve……………….……….......….25.81
Outlets lever…………………….........……9.83
1895 lamps……………………….........……4.34
Blower motor, hoses, fittings……..…40.32
Hose fittings……………….…….......…….4.92
Spring for cowl door…………….....……1.67
Plastic epoxy…………………….......…….9.68
AC duct hoses………………….......……61.00

Total…………………........…………….$.176.89

[bollybib]

TEMPERATURE SENDER REVISITED

I needed the ½" NPT port on the passenger side of the intake manifold for the heater hose connection. However, it was occupied by the temperature sender (see my Post #20). I wanted instead to use the 3/8" NPT port in the driver side cylinder head. However, the parts books call for a sender with a ½" NPT connection for this application. I figured I could find something of equivalent performance in 3/8" NPT so I searched through the Echlin catalog until I found a sender of a resistance range that was close to the specified TS6469. I found a TS6729 that came pretty close.

TS6469……...368 ohms @ 100 deg..…80 ohms @ 220 deg.…Range=288 ohms…(1/2" NPT-button)
TS6729…...…339 ohms @ 100 deg…..35 ohms @ 220 deg….Range=304 ohms…(3/8" NPT-stud)
Difference.…..29 ohms @ 100 deg…...45 ohms @ 220 deg…….…..…16 ohms

I obtained a TS6729 and installed it. I started the engine cold, and watched the gauge needle head toward hot very quickly and nearly peg after just a few minutes of engine operation. Upon further research, I discovered that one solution to temperature sender range problems is by adding an inline resistance. Like this one for example - - - > http://www.parts123.com/parts123/yb....Z5Z5Z50000050#

Based on my comparision of the specified TS6469 sender versus the proposed TS6729, I figured that adding 50 ohms would make it work OK. I went to Fry’s and bought a couple of trimpots and several values of fixed resistors so I could experiment and find a good value to use. Then I made up an assembly using a 100 ohm trimpot mounted on a surplus terminal board I had on hand, some solid wire and solder, and epoxy to hold the parts together and insulate everything.




The old loom covering the sender wire was shot so I installed a new loom over it. I rerouted the sender wire and secured it.


I set the trimpot to 50 ohms and installed it inline with the new sender and then started a cold engine. I waited until the engine was fully warmed up and then adjusted the trimpot until the needle was almost above the R in TEMPERATURE. I later measured this trimpot resistance at 41 ohms.

With this arrangement, the needle on the temperature gauge at fully warmed up is almost to halfway. I like it in this position better than before. The needle also moves off cold sooner, probably because the sender is in the head and not in the manifold. With the trimpot installed, I can adjust the resistance and get the gauge to where I feel it gives the best indication. I intend to replace the trimpot later with a fixed inline resistance for a more secure installation under the hood.


Fully warmed up with TS6729 and trimpot at 41 ohms, the needle is above the R


Same operating temperature with TS6469, the needle was above the E

With the sender relocated, I had a place to connect the heater hose to the intake manifold.

Temperature sender TS6729………$..16.24
Resistors…………………………….........…..9.51
Electrical terminals…….……….....….…..6.47

Total……………………...........…………$..32.22

[oldman3]

Holy **** Jim, that's a heck of a write up. I need you by my place now, I have a OT (68 Firebird) that I'm working on and I got a ton of none working underdash stuff for you. Nice job.....Jim

[bollybib]

Hi Jim

Ya I do go off the deep end on these posts.,,.but I enjoy doing them.

Seems like everything just falls apart under-the-dash after 40 years or so. One thing I liked about this HVAC project was the relative ease of access to everything. This truck stuff is a lot easier to get to than a passenger car for sure. And it's not too hard to take the seat out to make it even easier.

Sure I'll head on over and fix that Firebird stuff up for ya, no problem, sounds like fun. And now that I have this reliable C20 with heat I could drive my truck there in comfort. Let's see.,,..from my house that works out to,.,.,1,762 mi. x 2 = 3,524 mi round trip and @ say 12 mpg that would be 294 gallons of gas at say $4/gal = $1,175 ! Ooops, I'd have to dip into my IRA

Good luck on the 'bird. Looks like there are a couple of forums online for these cars. Let me know if you start posting.

[bollybib]

EVEN MORE MISCELLANEOUS FIXITS (1 OF 5)

I’m convinced there is an infinite supply of stuff to fix on this truck.,..,..

-New wire ducts and harness-
Both of the plastic wire ducts were shot so I got new ones. The wire harness vinyl tape, after years of being subjected to the underhood environment, gets brittle, unwinds, or is removed by POs. I got a roll of new stuff and reharnessed here and there. The original wiring hasn’t been fkd with too much, so I lucked out on that.

.............
Old duct at radiator support...............................................................New ducts at firewall and radiator support

[bollybib]

EVEN MORE MISCELLANEOUS FIXITS (2 OF 5)

Little by little, the engine compartment appearance has improved since I bought the truck. I’m not wanting to make it look primoshowyshiny, it’s too much work to keep it that way. For example, so far I haven’t painted a thing. All I do is clean clean clean. I want everything to be reasonably clean, free of excessive oil and grease, neatly arranged, and secure. It makes for a pleasant place to work and a nice space to look at…

January 2011October 2011
January 2011October 2011

Not a huge difference, but it is much neater and cleaner than it was a few months ago.

[bollybib]

EVEN MORE MISCELLANEOUS FIXITS (3 OF 5)

-New arm rests-
The color, although advertised as saddle, is more like brown. The quality of construction and the molding details do not accurately reproduce an original. But, they look OK and are more comfortable than the OG ones that were cracked and separated on the top surface.

Repro…………………………………...........................................................…..OG


-New taillight trim-
The existing piece was whacked and had been drilled and all the holddown clips were missing. This trim piece is relatively inexpensive so I got a new one. The uppermost clip holddown tab broke off right away but it stays flush once installed so nevermind that. One backup light lens screw was missing so I installed a new one.

[bollybib]

EVEN MORE MISCELLANEOUS FIXITS (4 OF 5)

-New radio antenna-
I was using the one that belonged on my Vette but it was getting corroded from being outdoors all the time. I bought a generic antenna at O’Reilly and put that one on the truck instead.



-New glove box liner-
The old one was totally thrashed and it was dark in there. The new one looks real nice and is now lit.



-Got the windshield washer to work-
I spliced in a new length of hose under the hood to reach the reservoir and reconnected the loose supply hose to the pump under the dash and the washer went right to work when I pushed the button.



-Brake adjusting hole plugs-
I removed the knockouts in the OG rear drums so I could adjust the brakes if necessary and now they’re plugged like they should be.

[bollybib]

EVEN MORE MISCELLANEOUS FIXITS (5 OF 5)

-Cleaned the horn contact surfaces in the steering wheel-
Pressing the horn button didn’t always result in a honk. After I cleaned all the rust off and got all the dirt out, it worked fine. The single horn sounds a little wimpy to me so maybe I’ll install duals or something louder in the future to get more robust truck-like HONK !



-Repaired the turn signal lever-
The turn signal lever was real looseygoosey. Turned out the plastic was cracked where the lever screw threads into the unit. I epoxied the screw hole and lever contact surface and then screwed down the lever. I got much firmer action afterwards.



Tape, terminals, ducts, loom…………..$.42.63
Arm rests…………………..........……………..37.52
Taillight bezel and hardware…...…………20.95
Antenna…………………............………………15.21
Glove box liner and hardware…...……….16.80
Brake hole plugs……………..……........…….0.77

Total………………...........…………….……$.133.88

I got a lot of stuff done on this truck in the past few weeks. I just ordered a new CST-style seat cover but it won't be here for a month or so. I'm still looking at steering wheels trying to decide WTF I want to do. Other that that, all is well, I drive this thing all over the place now.

Thanks for reading and keep on truckin'.

[yuccales]

Can't wait to see how your seat cover works out. I'm getting ready to do some things I've put off for awhile, seat cover is one of them. BTW, that pic of your truck at the beach is cool!

[oldman3]

Jim, I enjoy each and everyone of your post, they are very informative with lots of pics and the cost. By the time your done we can all print your post and have a great assembly/cost book....Jim

[67chevy1series]

wow im so glad i have a service manual. because a/c stuff is tightly put in these dashes and theres alot of crapola in there that has to be correct to function... ad i also want the a/c to work lol. jim thats a really nice write up... alll of them! it is helpful for me.

[VA72C10]

Thanks again for the detailed posts and writeup!!! Have you kept a running total? These fix-ups certainly add up!

[bollybib]

Originally Posted by yuccales

Can't wait to see how your seat cover works out. I'm getting ready to do some things I've put off for awhile, seat cover is one of them. BTW, that pic of your truck at the beach is cool!

A new seat cover will make a huge difference. The repro color won't be an exact match to original, but the colors of original saddle interior components didn't exactly match one another from the factory anyway. So I'm hoping that a new "light saddle" will fit in nicely. Like any other project, there are various problems with the seat that need to be fixed, too. It should be an interesting project and fun to write up.

Thanks about the pic. The saddle color blends nicely in that setting.