Complete new radiator experiment for $225

tyler

Active member
Jun 22, 2013
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Waking this thread up, as my engine rebuild is in the coach and running! A few more discoveries and adaptations I thought I would note:

Two nicopp 5/16 pre-flared brake lines (part number cn-540 at Advance) per direction of transmission fluid to the cooler worked pretty well. Custom
length would be better, but I have never had success with rented flaring tools, so bought pre-flared. Even with the eight inches difference in height
going into passenger side radiator tank. I bought the $8 Harbor Freight bender and it worked fine.

If you put this radiator in the original frame, you will need an actual ACDelco RC32 radiator cap, as the throat sits lower in the frame and the
widely available caps have ears to help turn it - no clearance. RC32 is round, and i'm going to tack little tabs on top like many gas caps have to
grip.

The overflow nipple is now on the back, and takes a 3/8 rubber hose, I believe a little bigger and longer than OEM

I ended up putting my four inch PVC brake booster vacuum reservoir in the open space at the bottom of the radiator frame. If not for the extra
thickness of the end caps, the four inches would be a perfect fit. RX7 oil cooler will end up in front frame section. Oil cooler is not hooked up yet,
as ambient temp isn't above 75 now and I can iron out those connections later.

The Dorman 926-276 rubber mounts worked in my new square bottom shelf, and I used OEM rounded radiator rubber mounts against the original frame top.

No road test yet, but coolant temp gauge movement seems thermostat driven - an appropriate cycling from 3/8 to 1/2 with Napa sender and 195
thermostat. Hoping to settle that with better thermostat.

As a clarifying reminder, this experiment is putting in a readily available radiator that can be had for $131 (at Advance after coupon). It does
requre an oil cooler solution (external or temporarily go without). The title of $225 included a new external oil cooler purchase. In theory, you just
need a shelf at bottom of frame of some sort four inches up to hold new radiator. The whole project has been more fiddly than I expected, but nothing
new there.

--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
While I understand that "WE" are trying to "adapt today's technology to yesterdays coach" of which we need to to keep these coaches on the road, case
in point the AC unit up front is crap in any year, you can upgrade your existing radiator to a heavy duty core at 13 fins per inch.

Even in lightfoot heavily taxed California I found someone to rebuild it. Do I need to after all these years, no, but with a new engine I did it and I
know that it fits. so far it stays right near the 180 degree tstat temperature.
--
1974 GMC Sequoia 26'
 
What do you propose for front AC upgrade. Mine sucks and blows.

> While I understand that "WE" are trying to "adapt today's technology to yesterdays coach" of which we need to to keep these coaches on the road,
> case in point the AC unit up front is crap in any year, you can upgrade your existing radiator to a heavy duty core at 13 fins per inch.
>
> Even in lightfoot heavily taxed California I found someone to rebuild it. Do I need to after all these years, no, but with a new engine I did it
> and I know that it fits. so far it stays right near the 180 degree tstat temperature.
>
> Quite honestly I don't know why you want to throw all that brass in the dumb anyway.

--
1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
 
The stock dash ac in my 77 worked just fine compared to other more modern
vehicles I have owned. And it was stock.

Sully
Bellevue wa

On Mon, Nov 9, 2020 at 8:12 PM Mike Hamm via Gmclist <

> What do you propose for front AC upgrade. Mine sucks and blows.
>

> > While I understand that "WE" are trying to "adapt today's technology to
> yesterdays coach" of which we need to to keep these coaches on the road,
> > case in point the AC unit up front is crap in any year, you can upgrade
> your existing radiator to a heavy duty core at 13 fins per inch.
> >
> > Even in lightfoot heavily taxed California I found someone to rebuild
> it. Do I need to after all these years, no, but with a new engine I did it
> > and I know that it fits. so far it stays right near the 180 degree tstat
> temperature.
> >
> > Quite honestly I don't know why you want to throw all that brass in the
> dumb anyway.
>
>
> --
> 1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
>
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77 coaches had fairly good A/C units. Earlier ones suffer from poor air movement in the A/C - heater box, but the compressor has a lot of excess
capacity. Adding another (outboard) evaporator and fan solves the heat for most folks.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell