Re: [DML] radio bezel/blower repair

["Walter Coe" <Whalt@xxxx>]

> Water collects at the blower bottom through
> the cooling tube, suggest drilling small drainage holes when you have
> it out or replacing it. Better still is to increase tube penetration
> into the duct by cementing a smaller ID tube into the larger one.

Increasing tube penetration probably isn't going to help much because there
is already a small lip where the tube goes in. Any water that could puddle
there is far more likely to settle on top of the blower motor before it
makes it up hill into the tube. Any water on top of the motor housing is
going to easily find its way in there. I mentioned on the DML before that I
used silicone caulk to fill in all the seams to keep the water out. Someone
objected saying that these holes are important to air circulation through
the motor, but I disagree. There are large holes specifically for
circulation under the raised area of the squirrel cage, and those I left
alone. Adding drainage holes in the bottom of the motor housing is an
interesting idea, but I doubt it will be effective. Any one hole will need
to be large enough such that the weight of the water will exceed the
strength of the surface tension. How about someone making a blower motor
that is water proof & rust proof?

> I recall reading that DMC had issued an old
> service note to reduce the R12 charge down from 2.8 pounds
> to 2.2 pounds, anyone familiar with that note?

Yes, I've seen 3 sources, and each gives a different specification. The 3rd
source being the '81 owners manual.

> I'm machining tig welding up a new SS pickup assembly for the fuel
> pump. It'll replace the hose and be a straight drop down (or slight
> offset) to a custom SS baffle assembly. Anyone tried this kind of
> thing before? Have to keep the return line away from the baffle or
> may have problems when the fuel level is low (proper baffle design
> will prevent this.) This could explain why some of you are having
> suction problems even with the spring installed.

I don't see much of a point in a custom baffle since the OEM isn't too bad
in my opinion (unless you don't like the thought of paying $92 for a rubber
hose that may need to be replaced in another 20 years). Many D's were made
with the lower part of the fuel baffle missing, and I think I heard that
this part was unavailable(?). But a friend just bought a new one from PJ
Grady which I installed for him today. Are these reproductions or NOS?

Can you explain the problem you see with the OEM fuel return line in the
baffle?

I had thoughts about making a custom baffle out of the bottom of a #2 PETE
plastic bleach bottle, but that was just a fleeting thought. Since fuel
cans are made of that kind of plastic, I figure it would work if it could
take the heat.

I had thoughts about making a SS fuel baffle (in addition to an entire tank
as well), so I'm curious to see what you are up to. Unlike the OEM,
whatever you come up with is going to have to be small enough to fit through
the fuel pump opening. I'm visualizing something either the size of the
fuel pump hole (round) or oval-shaped. What I like so much about the OEM
setup is that the suction screen sits very low without conducting too much
vibration from the pump. Eliminating the long flexible suction hose means
proper height of the fuel suction screen is going to be touchy -- too low
and it will conduct vibration; too high and it will suck air when the tank
is low. I would try to design it so that the baffle fills faster than it
empties, but still have the suction low enough so that it won't suck air
when you first start the car from an almost empty tank, i.e., the level in
the baffle will be as low as the rest of the tank.

> Changing most of the coolant hoses under the car to PTFE under
> stainless flex used in aircraft, and SS coolant bellows for supply
> and return at the engine. Anyone done this, or anything else, to
> improve MTBF of the cooling system?

Excuse my stupidy, but what does MTBF mean? I think that the kind of hose
you are talking about is the same or similar kind of material as the SS
braided clutch line upgrade & Marty's brake lines. I doubt that you will be
able to fit/stretch these the same way as regular coolant hoses. It seems
to me that you would need to attach special fittings. I see a lot of
mock-up versions at car shows, but to me it looks really silly seeing hose
clamps that are made to look like compression fittings. Someday I want to
replace my refrigerant lines and am thinking that I want to use PTFE? under
stainless flex. If this is what I think it is, it is commonly used in
commercial refrigeration systems.

> Going to change the wiring also. Studying the schematic shows an
> appalling lack of design expertise.

I think your opinion is too kind. :-) I'm happy doing the basic "vendor
approved" modifications; although, I would be happier with an entirely new
wiring system. The problem is that the car will probably outlast me. And I
love my car enough that I don't want the next owner to have a hard time
figuring out what I did differently. How about designing an "open source"
replacement wiring diagram and go into the wiring business. Make & sell a
standardized drop-in replacement electrical system that is standardized
(without making every other wire brown!)

Gary, welcome to the DML. It's a pleasure exchanging ideas with technically
minded people like you.

Walt Tampa, FL