85lebaront2

Vivek. I added AC to my 1977 F150 and it was a bear of a job. the firewall opening was nowhere near large enough, the dash vents weren't there etc. It was easier changing from a 300 six with a C4 to a 390 and C6. You will find the same issue on yours as the fresh air vent system wasn't on the Bullnose trucks, the Bricknose trucks have the inside ducts so converting one of them is easier.

On the Chrysler ATC systems, the FWD models had two different designs, the first was all vacuum controlled except for the blend door, which had a servo motor. They were built as a semi-automatic or full automatic system and had a power module with a power transistor for the fan and 5 single acting vacuum valves two relays, one for the high fan and one for the AC compressor clutch. The control head was the only major difference between semi and full auto systems. The air inlet door was an all or nothing style, either recir or fresh. The older systems had a 20% fresh/80% recirc position that was used in the AC mode as it came off max cooling to reduce the system shock of hot humid air but still providing ventilation. I am adding a bi-level function as the manual and semi auto units had and that the earlier AutoTemp and 1st version AutoTemp II had and Mercedes-Benz had on their early AutoTemp II clone. Since these pre-date the FMVSS requirement that loss of vacuum defaults to defrost. These used bi-directional vacuum actuators, where the newer sytems are single direction with a spring for the default action. Both the mode (panel, bi-level or floor) and the defrost (floor, mix or full defrost) have two nipples, one at the end away from the rod and the other on the side. The system has two defrost modes, lo and hi, lo is temperature blended and hi is full heat, high blower. On both of these (bi-level and low defrost I need a mid position on the doors so will use some solenoid valves to achieve this.

Jim, you should have heard the heater fan in my 1961 220Sb, it roared on high, but still didn't move much air. They had an axial fan that sat in the center of the air inlet scoop and blew downward through the two heater cores where a pair of doors (one on each side) were used to direct it up fro defrost or down for heat.

Welcome indeed, glad to have you in our group. AOD throttle linkage can be touchy, if the truck doesn't fell like it is lugging or hunting between 3 & 4 then the adjustment is probably good.

I was going to use bricknose door panels on Darth, but ended up going with aeronose because of the dash. The aeronose wing vents are truncated at the front in order to clear the instrument pod on the left and the defroster blled on the right. I did transfer the armrest supports due to the higher position. I also used the rear doors from a 1996 crewcab, I replaced all the plastic inner handles with metal ones and kept the 1986 door latches and rods, so no stretching cables.

One of the other things I have been planning on long term is a different ATC system. The ones built for the FWD platforms were mostly semi-automatic meaning mode selection might be automatic but blower speeds were manually set. Temperature control was definitely automatic. Back in the late 60s into the mid 70s, Chrysler had what they called "AutoTemp", possibly a play on their AirTemp line of home and industrial air conditioning units. The last iteration of the AutoTemp was the 1974 AutoTemp II that was discontinued when the only RWD cars were the Aspen and Volare. For years Chrysler vehicles had a sandwiched evaporator and heater core located underhood and temperature control was done with the heater through a thermally controlled flow valve which once set would do a pretty good job of maintaning the set temperature. The early AutoTemp and the first versions of the AutoTemp II were designed around the sandwiched core design rather than a blend door design. Essentially the under hood portion had the blower and the two sandwiched cores, inside were the distribution ducts and the fresh/recirculating air door. This basic design wasn't changed until the early to mid 70s and there were a number of different water control valve designs, the last of which was the most elaborate, this had both supply and return lines connected to it and on a manual system, a vacuum control fed through a temerature sensing control valve so that the set reheat temperature would be pretty well constant unless the temperature setting was changed. On the AutoTemp II this valve was replaced by a servo valve that also incorporated fan speed and vacuum mode controls. When the system was changed to a blend door design, the servo was moved inside the car and now operated the blend door through a lever and connecting link. The previous version, with the big servo water flow control valve showed up on Mercedes-Benz upper models starting in 1975. When I was working for the Mercedes-Benz dealer, they did not have a tester for the systems. I took my Robinair ATC tester in and drew a pair of the mating plugs for the M-B system, wired them into my tester and used it to test and repair the M-B units. top picture is the system controls, less the vacuum harnes laid out for electrical testing bottom picture is the Robinair ATC system tester

The 4.6L six cylinder has a gear driven camshaft, and if my memory is correct, it has a phenolic cam gear to reduce noise. Have you tried checking the timing to see if it is off?

I see I'm not the only one with a set of Alcoas on his truck. Nice looking wheels!

Welcome to the group! I'm a bit further away than Gary is, but will definitely try to help resolve the problems.

Gary, then you would be 2 grumpy old men.😈

One other thing, I used to see all the time on GM products with the HEI system. One weekend my USMCR 1st Sgt had his "Air Force Staff Car" a Chevy Biscane, loose the ignition going home. The coil is powerful enough to burn a hole right through the distributor rotor, causing exactly what you describe.

Definitely a nice truck, glad to have you with us.

Oly, I don't suppose you have seen a red LHD Shelby GT350 around. Current owner is in Sydney NSW.

I will give you and anyone else with a Bullnose a suggestion. The issue with the drains clogging is caused by leaves falling (or being blown) through the cowl grille slots, Ford changed this in 1987 by going to one that has lots of little holes. On a Bullnose, a piece of screen, preferably plastic, cut to fit, will keep the leaves out, but still let plenty of air in. I can't claim credit for this idea, I saw it on a Chevy 1 ton van while I had the front and part of the engie disassembled.

Jim, I count 15 kegs. The boys down under got some really neat engines we couldn't get here. Just think what a 300 crossflow would have been like.