1961 cadillac conversion

[ice-n-tropics]

in humid weather with humid air bypassing evap, and fresh air entering fan (Window partially down on recir.), frost will blow out of louvers.
hotrodac

[Tim]

in humid weather with humid air bypassing evap, and fresh air entering fan (Window partially down on recir.), frost will blow out of louvers.
hotrodac

Hey Ice. Hope all is well and fishing is good.

[cadillac matt]

the way the system is designed is that 1 fan blows through 2 separate sets of ductwork. a flapper door switches between them with no blending. so on hot all the air comes out the floor or defrost, and on a/c all the air comes out the dash vents. all that seems to work. i had considered the core freezing up, but it doesn't seem like the airflow ever changes. could the core freeze internally? would a partially blocked core cause this? the core was modified to fit by old air products to accept the ot and the accumulator. do i need more air flow? should i push this thing out side and light a match to it?
thanks guys for all your help.

[bohica2xo]

I have no idea what sort of core they provided. A large, folded fin plate style evaporator like this was common for cars that size:


https://www.rockauto.com/en/moreinfo.ph ... 60&jsn=917

[cadillac matt]

it looks like a original type core with the inlet and outlet changed. i don't believe it's a parallel flow type. it's big.

[cadillac matt]

final update.
after all the f-ing around, i figured it out.
i bought a brand new custom evap core for this project. the core was partially obstructed. when the system was working, only the 1st inch or so of the core would get cold. the rest would be room temp. sent it back and they made me a new 1.
success!! a chilly 32* at the vents today. woo hooo!!!

[tbirdtbird]

YAY!

I too have had a brand new core blocked right out of the box.
Now I blow dry compressed air thru everything before installing.
We have a commercial dryer (actually a small compressor/evap/condenser- Speedair brand) in series with our shop air because we need super dry air to paint cars in our booth

[cadillac matt]

the funny thing is you can blow through it, it just only goes through the 1st inch or so.

[tbirdtbird]

does that sound right?

[Tim]

I know the OP has apparently switched to an R4 (meh), but for others looking for similar displacement (~10ci, 160-170cc) compressors for a Sanden SD5/SD7 style ear-mount bracket, two notable choices are:

Seltec TM-16HS or TM-16HD

Sanden Enhanced SD7H15

The ear-mount Seltec is available in the common 6 and 8 groove serp (10 and 12 are also available) and V-belt (1A, 2A, 2B) configurations with a 12V or 24V clutch. The ear-mount Sanden Enhanced SD7H15 with a 12V clutch is only available in A2 V-belt or PV8 serp. If your engine uses a PV6 you can either run the PV8 pulley with 2 unused grooves, or buy the PV6 pulley and swap it on. The Seltec is available in several head configurations including the popular vertical o-ring and rear horizontal pad, while the Sanden enhanced is only available in rear horizontal pad. If you want o-ring ports on the Sanden you simply need one of the adapter manifolds to go from horizontal pad to vertical threaded o-ring ports. The Seltec and Sanden with horizontal ports both use the same manifolds, so you can use a "Sanden" manifold on a Seltec or vice-versa.

Even though the Sanden is a bit smaller in displacement (154.7cc) vs the Seltec (163cc), it pumps the same amount of gas at idle, and as RPM increases it's capacity also increases compared to the Seltec TM-16. This isn't to say that the Seltec is inadequate. On the contrary, it pumps plenty of gas. It's just that the Enhanced SD7H15 pumps a bit more. Either one will get the job done. In my experience the Seltec is quieter and smoother, even though the Sanden has an extra cylinder, but the difference is tiny if it even exists at all. Reliability and longevity is a wash; they're both excellent compressors (so is the Denso 10PA & 10S series, but sadly they don't make a Sanden-style ear mount version).

One last thing: don't buy Chinese clones of these or any other compressor! Get the real deal! Real Sandens and Seltecs can be had for little more than the Chinese clones if you shop around. Chinese compressors are cheap for a reason. If the Sanden doesn't say "Made in USA" or the Seltec doesn't say "Made in Japan", go elsewhere. Don't listen to anyone who says the Chinese compressors are "just as good as" (or, laughably, "better than!") the real deal. Saving a few bucks with a Chinese compressor is false economy. Don't do it!

I see the same failure rates with OEM as I do with After Market. So go figure!