Vintage Air mounting modification

[boat737]

I just couldn't live with mounting the blower and evaporator (or is that a condenser? It's been 45 years since my one air conditioning class) with those little sheet metal screws into plastic. So in the spirit of "If it's worth doing, it's worth over-doing" (maybe that should be my new motto), I made a couple of little brackets out of 1/2" wide, .090" thick aluminum stock to better, more securely mount it all up.

The two longer pieces fit on the inside of the evaporator top and bottom over the existing holes. The top piece is slightly shorter than the bottom because of the tapered evap housing. A third piece is cut to fit just inside of the gap at the bottom of the air passage. Much nicer than filling it all up with a ton of silicone. I drilled and tapped eight holes 6-32 for the screws to mount, which act as studs through the housing, through the firewall, and into the blower housing. Finished off with 6-32 nyloc nuts and washers. The short piece at the bottom I also attached to the inner bottom bracket by 6-32 counter sunk screws. I tapped them into the bracket, but a nyloc nut on the inside would work just as well. I J-B Weld'ed the eight screws into their brackets so they wouldn't back out while tightening the nyloc's.

I haven't permanently mounted the housings yet because I want to do a bit more wiring cleanup behind the dash. When I do, I'm planning on using a small amount of silicone around the air passage hole, on each side of the firewall to seal it up.

Also, the nuts on the top are a piece of cake to screw on. The bottom four are another matter. Two of them are pretty accessible, but two are pretty well hidden in the blower housing. I may well have to design a tool to start those nuts on the studs, or find a 10 year old kid with small hands to put them on. It looks doable, but only after lots of cursing and swearing I'm sure.

IMG_0540 small.JPGIMG_0537 small.JPGIMG_0543 small.JPGIMG_0541 small.JPGIMG_0542 small.JPG

[WIS89]

Boat-

I like the creativity. While I have never heard of anyone having a problem with the mounting, I have to agree with your point of view; don't just engineer it, over-engineer it!

I have saved your post for when I install my AC. Thanks!

Regards,

Steve

[boat737]

Update Part 1:

I wasn't so sure about feeding the heater blower with engine compartment air (or fumes) so I decided I would tackle fabricating a shroud. I know a lot of threads say it isn't needed, but a few thought it was. And since my high school chemistry class teacher said that CO (carbon-monoxide) is a colorless/odorless gas that can kill you, I figured "...and why not?"
(Famous quote from the great movie "This is Spinal Tap": Asked to write his own epitaph, David St. Hubbins says, "Here lies David St. Hubbins... and why not?")

I've finished making my heater shroud. I started by making a prototype from thin cardboard. It's mostly .040" aluminum, but the 3" hose rings and flanges are .056" stainless. I wasn't sure if the ducting would bounce around and fatique harden aluminum over the years, plus, stainless is easier to weld, and I already had some 3" stainless tube laying around.

When I designed and fabricated it, I wasn't even sure it would fit because I didn't have the engine in the car. I knew it would be close, but wouldn't know for sure until the engine install. Got the engine in now and the shroud fits. It has over an inch clearance from the right side valve cover. The heater hose 90 degree fittings are closer though, with about 5/8" clearance to the valve cover. I figure even with the engine bouncing around a bit in the motor mounts, it should be fine. Close, but not hitting.

Once I started fitting it to the firewall, I had to do some major trimming on the lower flange to clear the heater hose fittings, grommets, and my existing wiring through the firewall. I also cut a slot for the blower motor wires to exit the shroud. It all fit's, very close clearances, but fits.

The extra 3" flange is for mounting on top of the PS footbox for air to feed to the heater shroud. No valves or waste gates used, just footbox air to the shroud.

[boat737]

Update Part 2:

I have now mounted the heater blower motor, heat-exchanger, and shroud. Every thing is pretty tight, but it all seems to fit. I used silicone around the cockpit/heat-exchanger side of the firewall, but not on the engine/blower motor side. I used some very thin high-temp (oven) insulation around the edge of the shroud. I couldn't seal the bottom of the shroud "air tight", because of the pipes and grommets, but it's pretty well sealed. I thought of using some silicone to seal it up, but decided it would be too big of a mess to try that. It's good enough.

The heater modification I did to mount the heater and blower fit perfectly. Six of the eight ny-lock nuts went on easy-peasy. The last two of them took some ingenuity and a few brain cells to figure out. It's pretty darned cramped on the bottom side of that blower motor. The first one I ended up putting some sticky glue on my finger tip, and sticking the nut to it. I contorted my hand up and under the blower fan, twisted my finger around and got the nut started. (the glue eventually came off my finger tip a week later.)

For the last and hardest one, I had to take some 16 gauge wire, pull the copper strands out, and use the rubber sheath as a holder-starter-twister. I screwed the nylon part of the ny-lock onto the end of the rubber, then fished it into the small cavity, held it there with one finger, and twisted the sheath. Eventually, the nut started. Next, the little 5/16 end wrench wouldn't fit in the tight space of the flange (nor would a socket), so I ground down the sides of the box end of the combination wrench and got it in the cavity and on the nut. It took a while, turning 1/12 of a turn at a time, but got it snugged up. All of them were only snugged, since they are mounting plastic flanges on the blower motor.

I ended up getting the electric servo valve from Vintage Air for the heater lines. The manual switch seems to work fine, but I just couldn't find a good way to route the wires and cable from the manual rotary/push-pull switch. Just too many wires, ducts, fixtures, and stuff in the way. So I got two switches now, a rotary 3 speed blower switch, and a poteniometer/rheostat for the servo heater valve. I have already drilled a hole in the dash for the original rotary/push-pull switch, so I can use that for the new 3-speed rotary switch. But the rheostat for the servo has metric sized bushing and shaft on it. All my knobs and bezels are the Ron Francis billet aluminum pieces, and they won't fit on the metric switch. Of course they don't. So... I'm going to try to retrofit a knob and bezel onto that switch, which will allow me to drill another hole next to the blower switch and mount there. If I can't, I'll have to mount it under the dash and out of sight.

Even though the switches are not mounted, I hooked up the wiring and tried out the servo valve. It works great. Pretty slick.

The bottom line is I haven't mounted any of the heater switches, or the little ECU for the servo yet. I'm pretty much out of room behind the dash, so I'm thinking I'll have to mount the little ECU above the PS footbox in the engine compartment. We'll see.

I haven't pressure tested the cooling system with the heater plumbed in yet. I did do a suction test on the engine and radiator system (without the heater), and it held suction fine. Hopefully the added heater will hold up fine too. I ran out of hose clamps, so when I get those, this system will be done.

[Lancaster Lad]

Mr Boat

I like the idea and the way you built the cover. Now just another build delay when I get to that stage.
Thank you very much.

Cecil

[karlos]

Looking good - nice work. I also don't care for sheet metal screws in plastic. Did a similar modification by using Hi-Lok pins in place of the sheet metal screws.




These are commonly used on aircraft and spacecraft. It's a high strength fastener that requires no access to the head during installation. The pin is held from the front side with an allen wrench while the nut is tightened with a standard open end wrench. I just popped the pins in through the inside of the plastic housing, mounted the assembly to the firewall, and installed matching nylock nuts. No worries about these coming loose or falling out.

[boat737]

Very Clean Karlos. I debated whether or not to "mount" the servo valve. Right now it's just floating. Did you tap the 4 little holes to mount it?

[karlos]

So after saying I don't like sheet metal screws in plastic, I mounted the servo valve using self-tapping screws in plastic . Here's a view of the backside of the mounting bracket. The four screws go directly into the mounting bosses on the valve.




I considered running a tap into the bosses to cut machine threads but in the end decided that wouldn't really be any stronger than just using the self-tapping screws. The big difference between this and the heater housing is that the bosses on the servo valve are an inch or so deep, whereas the heater housing is less than a tenth of an inch. And the valve is a little compact lightweight thing. The self-tappers are more than adequate in this application.

Happy Thanksgiving!

[boat737]

Yeah, from my boat building/racing days, sheet metal/wood screws are generally only a temporary solution. Thru bolt is the way to go. Doesn't look like an option on that servo housing though. I did tap it for an 8-32, but haven't made a mount yet. Looks like a bit of a geometry problem to get the four holes drilled correctly too. One of my hoses is pretty short, so I'm not sure I want to mount it solid, with the firewall flexing a little. Probably not a problem, but then again, you never know. Still pondering.

[cgundermann]

I changed from the originals and went with a larger/longer aluminum self tapping screw. It holds strong, but really like those Hi Lok pins! What is a good source for those? Love that mounting bracket Karlos...

[karlos]

I buy them locally at an aircraft supply company called Boulderfly Tools in Boulder, CO. They do have an EBay store, and it looks like they sell Hi-Loks online. These do not come in a fully threaded variant, so if you decide to use them you'll need to make sure you order the correct grip size. The spec linked here will help you decode the part number: http://www.jet-tek.com/hi-lok-pins/hl20.php. I normally keep a small supply on hand covering a range of grip lengths. $3.95 for a quantity of 10, so fairly inexpensive to keep a handful around.

[cgundermann]

Thanks Karlos!

[hayton55]

Looks good fellas; just wondering which Vintage Air model are you using? Did they supply a complete kit or did you have to source the parts from their site yourself? I didn't see any mention of the type of louvers used; Whitby had some good ones with their kit but now thats a bust…any info would be quite helpful… thanks ...

[boat737]

I used the standard FFR supplied Vintage Air heater. I did not use the defroster vents, and bought two more of the eyeball vents for under the dash. Car is still in build process, so I don't have any input on their effectiveness.

[cgundermann]

Where did you get two more of the eyeball vents; Vintage Air? I'm doing the same for extra heat...

[boat737]

Yup, Vintage Air. Go to their website, and you'll find they have a few different styles of eyeball vents. I used the part number off of the package that the original eyeball came in to order it up. Not sure if I still have that part number, but give the VA tech a call and I'm sure they can match up a pair.

[cgundermann]

Thank you!